eZ80Acclaim!
®
Flash Microcontrollers
eZ80L92 MCU
Product Specification
PS013015-0316
Copyright ©2016 by Zilog, Inc. All rights reserved.
www.zilog.com
eZ80L92 MCU
Product Specification
This publication is subject to replacement by a later edition. To determine whether a later edition exists, or to request
copies of publications, visit www.zilog.com.
Document Disclaimer
©2016 by Zilog, Inc. All rights reserved. Information in this publication concerning the devices, applications, or
technology described is intended to suggest possible uses and may be superseded. ZILOG, INC. DOES NOT
ASSUME LIABILITY FOR OR PROVIDE A REPRESENTATION OF ACCURACY OF THE INFORMATION,
DEVICES, OR TECHNOLOGY DESCRIBED IN THIS DOCUMENT. ZILOG ALSO DOES NOT ASSUME
LIABILITY FOR INTELLECTUAL PROPERTY INFRINGEMENT RELATED IN ANY MANNER TO USE OF
INFORMATION, DEVICES, OR TECHNOLOGY DESCRIBED HEREIN OR OTHERWISE. Except with the
express written approval Zilog, use of information, devices, or technology as critical components of life support
systems is not authorized. No licenses or other rights are conveyed, implicitly or otherwise, by this document under
any intellectual property rights.
Zilog is a registered trademark of Zilog Inc. in the United States and in other countries. eZ80Acclaim!, eZ80, and Z80
are trademarks or registered trademarks of Zilog Inc. All other products and/or service names mentioned herein may
be trademarks of the companies with which they are associated.
PS013015-0316
eZ80L92 MCU
Product Specification
iii
Revision History
Each instance in Revision History reflects a change to this document from its previous
revision. For more details, refer to the corresponding pages and appropriate link in the
table below.
Date
Revision Level
Section\Description
Page No
March
2016
15
Chapter 11. Real Time Clock – added
clarification about leap year compensation when
BCD operation is enabled; updated Zilog logo on
title page and in header.
88
October
2006
14
On Page 114, Table 57, replaced “valid only if
INTBIT is 1” with " valid only if INTBIT is 0".
Removed Preliminary.
113
March
2006
13
Added the registered trademark symbol ® to
eZ80Acclaim! and eZ80.
All
October
2004
12
Formatted to current publication standards.
All
Timer Control
Registers
82
Clarified RST_EN
descriptions.
External Memory Read Correction to T6 label,
Timing
Clock Rise to CSx
De-assertion Delay
(Figure 48).
205
External I/O Read
Timing
Correction to T6 label,
Clock Rise to CSx
De-assertion Delay
(Figure 50).
208
Real Time Clock
Oscillator and Source
Selection
Clarified language
describing RTC drive
frequency.
89
February
2004
11
Revisions to BGR Divisor, UART text
September
2003
10
Modified to remove "zservice@zilog.com" and
other external hyperlinks.
PS013015-0316
108
Revision History
eZ80L92 MCU
Product Specification
iv
Table of Contents
List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Architectural Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
eZ80® CPU Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
New and Improved Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
RESET Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SLEEP Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HALT Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clock Peripheral Power-Down Registers . . . . . . . . . . . . . . . . . . . . . . . . . .
35
35
35
36
36
General-Purpose Input/Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIO Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIO Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIO Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIO Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
39
39
39
42
43
Interrupt Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Maskable Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Nonmaskable Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Chip Selects and Wait States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory and I/O Chip Selects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory Chip Select Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I/O Chip Select Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wait States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WAIT Input Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chip Selects During Bus Request/Bus Acknowledge Cycles . . . . . . . . . . .
Bus Mode Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
eZ80 Bus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PS013015-0316
48
48
48
50
51
51
52
53
53
eZ80L92 MCU
Product Specification
v
PS013015-0316
Z80 Bus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Intel Bus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Motorola Bus Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chip Select Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
53
55
62
66
Watch-Dog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Watch-Dog Timer Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Watch-Dog Timer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Watch-Dog Timer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
71
71
72
73
Programmable Reload Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Programmable Reload Timers Overview . . . . . . . . . . . . . . . . . . . . . . . . . .
Programmable Reload Timer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . .
Programmable Reload Timer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . .
75
75
76
80
Real-Time Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Oscillator and Source Selection . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Battery Backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Recommended Operation . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
86
86
87
87
87
87
88
Universal Asynchronous Receiver/Transmitter . . . . . . . . . . . . . . . . . . . . . . . .
UART Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UART Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UART Recommended Usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Baud Rate Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BRG Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UART Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
102
102
104
105
107
107
109
Infrared Encoder/Decoder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Infrared Encoder/Decoder Signal Pins . . . . . . . . . . . . . . . . . . . . . . . . . . .
Loopback Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
120
120
121
121
122
122
123
Serial Peripheral Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Flags . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPI Baud Rate Generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data Transfer Procedure with SPI Configured as the Master . . . . . . . . . .
125
126
128
128
129
130
eZ80L92 MCU
Product Specification
vi
Data Transfer Procedure with SPI Configured as a Slave . . . . . . . . . . . . 130
SPI Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
I2C Serial I/O Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I2C General Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transferring Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clock Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I2C Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
135
135
137
138
140
147
ZiLOG Debug Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI-Supported Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Clock and Data Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Start Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Register Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Write Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Read Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation of the eZ80L92 during ZDI BREAKpoints . . . . . . . . . . . . . . . . .
Bus Requests During ZDI Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Write-Only Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Read-Only Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Register Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
156
156
157
158
158
160
161
162
163
163
164
166
166
On-Chip Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction to On-Chip Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . .
OCI Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OCI Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OCI Information Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
182
182
182
183
184
eZ80® CPU Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Op-Code Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
On-Chip Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20 MHz Primary Crystal Oscillator Operation . . . . . . . . . . . . . . . . . . . . . .
50 MHz Primary Crystal Oscillator Operation . . . . . . . . . . . . . . . . . . . . . .
32 KHz Real-Time Clock Crystal Oscillator Operation . . . . . . . . . . . . . . . .
196
196
197
199
Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
External Memory Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
External Memory Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
PS013015-0316
eZ80L92 MCU
Product Specification
vii
External I/O Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External I/O Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wait State Timing for Read Operations . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wait State Timing for Write Operations . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Purpose I/O Port Input Sample Timing . . . . . . . . . . . . . . . . . . . .
General Purpose I/O Port Output Timing . . . . . . . . . . . . . . . . . . . . . . . . .
External Bus Acknowledge Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External System Clock Driver (PHI) Timing . . . . . . . . . . . . . . . . . . . . . . . .
208
209
211
212
213
213
214
214
Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Part Number Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
Precharacterization Product . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217
Document Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Document Number Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Customer Feedback Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
PS013015-0316
eZ80L92 MCU
Product Specification
vii
List of Figures
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
Figure 20.
Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.
Figure 26.
Figure 27.
Figure 28.
Figure 29.
Figure 30.
Figure 31.
Figure 32.
PS013015-0316
eZ80L92 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
100-Pin LQFP Configuration of the eZ80L92 . . . . . . . . . . . . . . . . . . 4
GPIO Port Pin Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Memory Chip Select Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Wait Input Sampling Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . 51
Wait State Operation Example (Read Operation) . . . . . . . . . . . . . . 52
Z80 Bus Mode Read Timing Example . . . . . . . . . . . . . . . . . . . . . . . 54
Z80 Bus Mode Write Timing Example . . . . . . . . . . . . . . . . . . . . . . . 55
IntelTM Bus Mode Signal and Pin Mapping . . . . . . . . . . . . . . . . . . . 56
Intel™ Bus Mode Read Timing Example (Separate Address and
Data Buses) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Intel™ Bus Mode Write Timing Example (Separate Address and
Data Buses) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Intel™ Bus Mode Read Timing Example (Multiplexed Address
and Data Bus) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
IntelTM Bus Mode Write Timing Example (Multiplexed Address
and Data Bus) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Motorola Bus Mode Signal and Pin Mapping . . . . . . . . . . . . . . . . . 63
Motorola Bus Mode Read Timing Example . . . . . . . . . . . . . . . . . . . 65
Motorola Bus Mode Write Timing Example . . . . . . . . . . . . . . . . . . . 66
Watch-Dog Timer Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Programmable Reload Timer Block Diagram . . . . . . . . . . . . . . . . . 75
PRT Single Pass Mode Operation Example . . . . . . . . . . . . . . . . . . 77
PRT Continuous Mode Operation Example . . . . . . . . . . . . . . . . . . 78
PRT Timer Output Operation Example . . . . . . . . . . . . . . . . . . . . . . 80
Real-Time Clock and 32KHz Oscillator Block Diagram . . . . . . . . . . 86
UART Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Infrared System Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Infrared Data Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Infrared Data Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
SPI Master Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
SPI Slave Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
I2C Clock and Data Relationship . . . . . . . . . . . . . . . . . . . . . . . . . . 136
START and STOP Conditions In I2C Protocol . . . . . . . . . . . . . . . . 136
I2C Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
eZ80L92 MCU
Product Specification
viii
Figure 33.
Figure 34.
Figure 35.
Figure 36.
Figure 37.
Figure 38.
Figure 39.
Figure 40.
Figure 41.
Figure 42.
Figure 43.
Figure 44.
Figure 45.
Figure 46.
Figure 47.
Figure 48.
Figure 49.
Figure 50.
Figure 51.
Figure 52.
Figure 53.
Figure 54.
Figure 55.
Figure 56.
Figure 57.
PS013015-0316
I2C Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clock Synchronization In I2C Protocol . . . . . . . . . . . . . . . . . . . . . .
Typical ZDI Debug Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Schematic For Building a Target Board ZPAK II Connector . . . . .
ZDI Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Address Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Single-Byte Data Write Timing . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Block Data Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Single-Byte Data Read Timing . . . . . . . . . . . . . . . . . . . . . . . .
ZDI Block Data Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended Crystal Oscillator Configuration
(20MHz operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended Crystal Oscillator Configuration
(50MHz operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recommended Crystal Oscillator Configuration
(32KHz operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ICC vs. Frequency (Typical @ 3.3 V, 25ºC) . . . . . . . . . . . . . . . . . .
ICC vs. WAIT (Typical @ 3.3 V, 25ºC) . . . . . . . . . . . . . . . . . . . . . .
External Memory Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Memory Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . .
External I/O Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External I/O Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wait State Timing for Read Operations . . . . . . . . . . . . . . . . . . . . .
Wait State Timing for Write Operations . . . . . . . . . . . . . . . . . . . . .
Port Input Sample Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPIO Port Output Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
100-Lead Plastic Low-Profile Quad Flat Package (LQFP) . . . . . .
138
139
156
157
159
159
160
161
162
162
163
196
198
199
203
203
205
206
208
209
211
212
213
213
215
eZ80L92 MCU
Product Specification
ix
List of Tables
Table 1. 100-Pin LQFP Pin Identification of the eZ80L92 Device . . . . . . . . . . . . 5
Table 2. Pin Characteristics of the eZ80L92 . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 3. Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 4. Clock Peripheral Power-Down Register 1 . . . . . . . . . . . . . . . . . . . . . . 37
Table 5. Clock Peripheral Power-Down Register 2 . . . . . . . . . . . . . . . . . . . . . . 38
Table 6. GPIO Mode Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Table 7. Port x Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 8. Port x Data Direction Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 9. Port x Alternate Registers 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 10. Port x Alternate Registers 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 11. Interrupt Vector Sources by Priority . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 12. Vectored Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 13. Register Values for Memory Chip Select Example . . . . . . . . . . . . . . 50
Table 14. Z80 Bus Mode Read States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Table 15. Z80 Bus Mode Write States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Table 16. Intel™ Bus Mode Read States (Separate Address and Data Buses) 56
Table 17. Intel™ Bus Mode Write States (Separate Address and Data Buses) 57
Table 18. Intel™ Bus Mode Write States (Multiplexed Address and Data Bus). 60
Table 19. Intel™ Bus Mode Read States (Multiplexed Address and Data Bus) 60
Table 20. Motorola Bus Mode Read States . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Table 21. Motorola Bus Mode Write States . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Table 22. Chip Select x Lower Bound Registers . . . . . . . . . . . . . . . . . . . . . . . . 67
Table 23. Chip Select x Upper Bound Registers . . . . . . . . . . . . . . . . . . . . . . . . 67
Table 24. Chip Select x Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Table 25. Chip Select x Bus Mode Control Registers . . . . . . . . . . . . . . . . . . . . 69
Table 26. Watch-Dog Timer Approximate Time-Out Delays . . . . . . . . . . . . . . . 72
Table 27. Watch-Dog Timer Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Table 28. Watch-Dog Timer Reset Register . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Table 29. PRT Single Pass Mode Operation Example . . . . . . . . . . . . . . . . . . . 77
Table 30. PRT Continuous Mode Operation Example . . . . . . . . . . . . . . . . . . . . 78
Table 31. PRT Timer Out Operation Example . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Table 32. Timer Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Table 33. Timer Data Registers—Low Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Table 34. Timer Data Registers—High Byte . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Table 35. Timer Reload Registers—Low Byte . . . . . . . . . . . . . . . . . . . . . . . . . . 83
PS013015-0316
eZ80L92 MCU
Product Specification
x
Table 36. Timer Reload Registers—High Byte . . . . . . . . . . . . . . . . . . . . . . . . . 84
Table 37. Timer Input Source Select Register . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Table 38. Real-Time Clock Seconds Register . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Table 39. Real-Time Clock Minutes Register. . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Table 40. Real-Time Clock Hours Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Table 41. Real-Time Clock Day-of-the-Week Register . . . . . . . . . . . . . . . . . . . 91
Table 42. Real-Time Clock Day-of-the-Month Register . . . . . . . . . . . . . . . . . . . 92
Table 43. Real-Time Clock Month Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Table 44. Real-Time Clock Year Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Table 45. Real-Time Clock Century Register. . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Table 46. Real-Time Clock Alarm Seconds Register . . . . . . . . . . . . . . . . . . . . . 96
Table 47. Real-Time Clock Alarm Minutes Register . . . . . . . . . . . . . . . . . . . . . 97
Table 48. Real-Time Clock Alarm Hours Register . . . . . . . . . . . . . . . . . . . . . . . 98
Table 49. Real-Time Clock Alarm Day-of-the-Week Register . . . . . . . . . . . . . . 99
Table 50. Real-Time Clock Alarm Control Register . . . . . . . . . . . . . . . . . . . . . 100
Table 51. Real-Time Clock Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Table 52. UART Baud Rate Generator Registers—Low Byte . . . . . . . . . . . . . 108
Table 53. UART Baud Rate Generator Registers—High Byte . . . . . . . . . . . . . 108
Table 54. UART Transmit Holding Registers . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Table 55. UART Receive Buffer Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Table 56. UART Interrupt Enable Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Table 57. UART Interrupt Identification Registers . . . . . . . . . . . . . . . . . . . . . . 111
Table 58. UART Interrupt Status Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Table 59. UART FIFO Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Table 60. UART Line Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Table 61. UART Character Parameter Definition . . . . . . . . . . . . . . . . . . . . . . . 114
Table 62. UART Modem Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Table 63. UART Line Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Table 64. UART Modem Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Table 65. UART Scratch Pad Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Table 66. GPIO Mode Selection when using the IrDA Encoder/Decoder . . . . 123
Table 67. Infrared Encoder/Decoder Control Register . . . . . . . . . . . . . . . . . . . 124
Table 68. SPI Clock Phase (CPHA) and Clock Polarity Operation . . . . . . . . . 127
Table 69. SPI Baud Rate Generator Register—High Byte. . . . . . . . . . . . . . . . 131
Table 70. SPI Baud Rate Generator Register—Low Byte . . . . . . . . . . . . . . . . 131
Table 71. SPI Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Table 72. SPI Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Table 73. SPI Receive Buffer Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
PS013015-0316
eZ80L92 MCU
Product Specification
xi
Table 74. SPI Transmit Shift Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 75. I2C Master Transmit Status Codes. . . . . . . . . . . . . . . . . . . . . . . . . .
Table 76. I2C 10-Bit Master Transmit Status Codes . . . . . . . . . . . . . . . . . . . .
Table 77. I2C Master Transmit Status Codes For Data Bytes . . . . . . . . . . . . .
Table 78. I2C Master Receive Status Codes . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 79. I2C Master Receive Status Codes For Data Bytes. . . . . . . . . . . . . .
Table 80. I2C Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 81. I2C Slave Address Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 82. I2C Extended Slave Address Register . . . . . . . . . . . . . . . . . . . . . . .
Table 83. I2C Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 84. I2C Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 85. I2C Status Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 86. I2C Status Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 87. I2C Clock Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 88. I2C Software Reset Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 89. Recommended ZDI Clock vs. System Clock Frequency . . . . . . . . .
Table 90. ZDI Write-Only Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 91. ZDI Read-Only Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 92. ZDI Address Match Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 93. ZDI BREAK Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 94. ZDI Master Control Register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 95. ZDI Write Data Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 96. ZDI Read/Write Control Register Functions . . . . . . . . . . . . . . . . . . .
Table 97. ZDI Bus Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 98. Instruction Store 4:0 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 99. ZDI Write Memory Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 100. eZ80® Product ID Low Byte Register. . . . . . . . . . . . . . . . . . . . . . .
Table 101. eZ80® Product ID Revision Register . . . . . . . . . . . . . . . . . . . . . . .
Table 102. eZ80® Product ID High Byte Register . . . . . . . . . . . . . . . . . . . . . .
Table 103. ZDI Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 104. ZDI Read Registers—Low, High and Upper . . . . . . . . . . . . . . . . .
Table 105. ZDI Bus Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 106. ZDI Read Memory Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 107. OCI Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 108. Arithmetic Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 109. Bit Manipulation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 110. Block Transfer and Compare Instructions . . . . . . . . . . . . . . . . . . .
Table 111. Exchange Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PS013015-0316
134
141
142
143
144
145
147
148
149
149
151
152
152
154
155
157
164
166
167
168
170
171
172
173
175
176
176
177
177
178
179
180
181
183
185
185
185
186
eZ80L92 MCU
Product Specification
xii
Table 112. Input/Output Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 113. Load Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 114. Logical Instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 115. Processor Control Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 116. Program Control Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 117. Rotate and Shift Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 118. Op Code Map—First Op Code . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 119. Op Code Map—Second Op Code after 0CBh . . . . . . . . . . . . . . . .
Table 120. Op Code Map—Second Op Code After 0DDh . . . . . . . . . . . . . . . .
Table 121. Op Code Map—Second Op Code After 0EDh . . . . . . . . . . . . . . . .
Table 122. Op Code Map—Second Op Code After 0FDh . . . . . . . . . . . . . . . .
Table 123. Op Code Map—Fourth Byte After 0DDh, 0CBh, and dd . . . . . . . .
Table 124. Op Code Map—Fourth Byte After 0FDh, 0CBh, and dd* . . . . . . . .
Table 125. Recommended Crystal Oscillator Specifications
(20 MHz Operation). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 126. Recommended Crystal Oscillator Specifications
(50MHz Operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 127. Recommended Crystal Oscillator Specifications
(32 KHz Operation) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 128. Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 129. DC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 130. AC Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 131. External Read Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 132. External Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 133. External I/O Read Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 134. External I/O Write Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 135. GPIO Port Output Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 136. Bus Acknowledge Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 137. PHI System Clock Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table 138. Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PS013015-0316
186
187
187
187
188
188
189
190
191
192
193
194
195
197
198
199
201
202
204
205
207
208
210
214
214
214
216
eZ80L92 MCU
Product Specification
1
Architectural Overview
Zilog’s eZ80L92 MCU is a high-speed single-cycle instruction-fetch microcontroller with
a maximum clock speed of 50 MHz. The eZ80L92 MCU is a member of eZ80Acclaim!®
family of Flash microcontrollers. It operates in Z80® compatible addressing mode (64
KB) or full 24-bit addressing mode (16 MB). The rich peripheral set of the eZ80L92 MCU
makes it suitable for various applications including industrial control, embedded
communication, and point-of-sale terminals.
Features
The features of eZ80L92 MCU include:
•
•
Single-cycle instruction fetch, high-performance, pipelined eZ80® CPU core1
•
Two Universal Asynchronous Receiver/Transmitter (UARTs) with independent baud
rate generators
•
•
•
•
•
Serial Peripheral Interface (SPI) with independent clock rate generator
Low power features including SLEEP mode, HALT mode, and selective peripheral
power-down control
Inter-Integrated Circuit (I2C) with independent clock rate generator
Infrared Data Association (IrDA)-compliant infrared encoder/decoder
New DMA-like eZ80 instructions for efficient block data transfer
Glueless external peripheral interface with 4 Chip Selects, individual Wait State
generators, and an external WAIT input pin—supports Intel-style and Motorola-style
buses Fixed-priority vectored interrupts (both internal and external) and interrupt
controller
•
Real-time clock with an on-chip 32 kHz oscillator, selectable 50/60 Hz input, and
separate VDD pin for battery backup
•
•
•
•
•
•
Six 16-bit Counter/Timers with prescalers and direct input/output drive
Watchdog Timer (WDT)
24 bits of General-Purpose Input/Output (GPIO)
JTAG and ZDI debug interfaces
100-pin LQFP package
3.0 V to 3.6 V supply voltage with 5 V tolerant inputs
1. For simplicity, the term eZ80 CPU is referred as CPU for the rest of this document.
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
2
•
Operating temperature range:
– Standard, 0 ºC to +70 ºC
– Extended, –40 ºC to +105 ºC
Note: All signals with an overline are active Low. For example, B/W, for which WORD is active
Low, and B/W, for which BYTE is active Low.
Power connections follow these conventional descriptions.
PS013014-0107
Connection
Circuit
Device
Power
VCC
VDD
Ground
GND
VSS
Architectural Overview
eZ80L92 MCU
Product Specification
3
Block Diagram
Figure 1 illustrates the block diagram of the eZ80L92 MCU.
Real-Time
Clock and
32 KHz
Oscillator
RTC_VDD
RTC_XIN
RTC_XOUT
I2C
Serial
Interface
SCL
SDA
BUSACK
BUSREQ
INSTRD
IORQ
MREQ
RD
WR
Bus
Controller
SCK
Serial
Peripheral
Interface
(SPI)
SS
MISO
NMI
RESET
HALT_SLP
eZ80
CPU
MOSI
ZiLOG
Debug
Interface
(JTAG/ZDI)
CTS0/1
DCD0/1
DSR0/1
Interrupt
Vector
[7:0]
Universal
Asynchronous
Receiver/
Transmitter
(UART)
DTR0/1
RI0/1
RTS0/1
Interrupt
Controller
JTAG/ZDI Signals (5)
WAIT
CS0
CS1
CS2
CS3
Chip
Select
and
Wait State
Generator
RxD0/1
DATA[7:0]
TxD0/1
ADDR[23:0]
Programmable
Reload
Timer/Counters
(6)
Watch-Dog
Timer
(WDT)
T0_IN
T1_IN
T2_IN
T3_IN
T4_OUT
T5_OUT
PHI
XOUT
Crystal
Oscillator
and
System Clock
Generator
X IN
PD[7:0]
PB[7:0]
8-Bit
General
Purpose
I/O Port
(GPIO)
PC[7:0]
IR_RxD
IR_TxD
IrDA
Encoder/
Decoder
Figure 1. eZ80L92 Block Diagram
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
4
Pin Description
100-Pin LQFP
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
60
59
58
57
56
55
54
53
52
51
PD7/RI0
PD6/DCD0
PD5/DSR0
PD4/DTR0
PD3/CTS0
PD2/RTS0
PD1/RxD0/IR_RXD
PD0/TxD0/IR_TXD
VDD
TDO
TDI
TRIGOUT
TCK
TMS
VSS
RTC_VDD
RTC_XOUT
RTC_XIN
VSS
VDD
HALT_SLP
BUSACK
BUSREQ
NMI
RESET
ADDR21
ADDR22
ADDR23
CS0
CS1
CS2
CS3
VDD
VSS
DATA0
DATA1
DATA2
DATA3
DATA4
DATA5
DATA6
DATA7
VDD
VSS
IORQ
MREQ
RD
WR
INSTRD
WAIT
ADDR0
ADDR1
ADDR2
ADDR3
ADDR4
ADDR5
VDD
VSS
ADDR6
ADDR7
ADDR8
ADDR9
ADDR10
ADDR11
ADDR12
ADDR13
ADDR14
VDD
VSS
ADDR15
ADDR16
ADDR17
ADDR18
ADDR19
ADDR20
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
PHI
SCL
SDA
VSS
VDD
PB7/MOSI
PB6/MISO
PB5/T5_OUT
PB4/T4_OUT
PB3/SCK
PB2/SS
PB1/T1_IN
PB0/T0_IN
VDD
XOUT
XIN
VSS
PC7/RI1
PC6/DCD1
PC5/DSR1
PC4/DTR1
PC3/CTS1
PC2//RTS1
PC1/RxD1
PC0/TxD1
Figure 2 illustrates the pin layout of the eZ80L92 MCU in the 100-pin LQFP package.
Table 1 lists the 100-Pin LQFP pins and their functions.
Figure 2. 100-Pin LQFP Configuration of the eZ80L92
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
5
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU
Pin No
Symbol
Function
Signal Direction
Description
1
ADDR0
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
2
ADDR1
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
3
ADDR2
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
4
ADDR3
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
5
ADDR4
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
6
ADDR5
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
6
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
7
VDD
Power Supply
Power Supply.
8
VSS
Ground
Ground.
9
ADDR6
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
10
ADDR7
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
11
ADDR8
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
12
ADDR9
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
13
ADDR10
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
PS013014-0107
Signal Direction
Description
Architectural Overview
eZ80L92 MCU
Product Specification
7
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
14
ADDR11
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
15
ADDR12
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
16
ADDR13
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
17
ADDR14
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
18
VDD
Power Supply
Power Supply.
19
VSS
Ground
Ground.
20
ADDR15
Address Bus
PS013014-0107
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
Architectural Overview
eZ80L92 MCU
Product Specification
8
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
21
ADDR16
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
22
ADDR17
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
23
ADDR18
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
24
ADDR19
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
25
ADDR20
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
9
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
26
ADDR21
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
27
ADDR22
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
28
ADDR23
Address Bus
Bidirectional
Configured as an output in normal
operation. The address bus selects a
location in memory or I/O space to be
read or written. Configured as an input
during bus acknowledge cycles. Drives
the Chip Select/Wait State Generator
block to generate Chip Selects.
29
CS0
Chip Select 0
Output, Active Low
CS0 Low indicates that an access is
occurring in the defined CS0 memory or
I/O address space.
30
CS1
Chip Select 1
Output, Active Low
CS1 Low indicates that an access is
occurring in the defined CS1 memory or
I/O address space.
31
CS2
Chip Select 2
Output, Active Low
CS2 Low indicates that an access is
occurring in the defined CS2 memory or
I/O address space.
32
CS3
Chip Select 3
Output, Active Low
CS3 Low indicates that an access is
occurring in the defined CS3 memory or
I/O address space.
33
VDD
Power Supply
Power Supply.
34
VSS
Ground
Ground.
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
10
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
35
DATA0
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
36
DATA1
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
37
DATA2
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
38
DATA3
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
39
DATA4
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
40
DATA5
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
41
DATA6
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
42
DATA7
Data Bus
Bidirectional
The data bus transfers data to and from
I/O and memory devices. The eZ80L92
MCU drives these lines only during Write
cycles when the eZ80L92 MCU is the bus
master.
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
11
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
43
VDD
Power Supply
Power Supply.
44
VSS
Ground
Ground.
45
IORQ
Input/Output
Request
Bidirectional, Active
Low
IORQ indicates that the CPU is accessing
a location in I/O space. RD and WR
indicate the type of access. The eZ80L92
MCU does not drive this line during
RESET. It is an input in bus acknowledge
cycles.
46
MREQ
Memory
Request
Bidirectional, Active
Low
MREQ Low indicates that the CPU is
accessing a location in memory. The RD,
WR, and INSTRD signals indicate the
type of access. The eZ80L92 MCU does
not drive this line during RESET. It is an
input in bus acknowledge cycles.
47
RD
Read
Output, Active Low
RD Low indicates that the eZ80L92 MCU
is reading from the current address
location. This pin is tristated during bus
acknowledge cycles.
48
WR
Write
Output, Active Low
WR indicates that the CPU is writing to the
current address location. This pin is
tristated during bus acknowledge cycles.
49
INSTRD
Instruction
Output, Active Low
Read Indicator
INSTRD (with MREQ and RD) indicates
the eZ80L92 MCU is fetching an
instruction from memory. This pin is
tristated during bus acknowledge cycles.
50
WAIT
WAIT Request Input, Active Low
Driving the WAIT pin Low forces the CPU
to wait additional clock cycles for an
external peripheral or external memory to
complete its Read or Write operation.
51
RESET
Reset
PS013014-0107
Signal Direction
Description
Schmitt Trigger Input, This signal is used to initialize the
Active Low
eZ80L92 MCU. This input must be Low for
a minimum of 3 system clock cycles, and
must be held Low until the clock is stable.
This input includes a Schmitt trigger to
allow RC rise times.
Architectural Overview
eZ80L92 MCU
Product Specification
12
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
52
NMI
Nonmaskable
Interrupt
Schmitt Trigger Input, The NMI input is a higher priority input
Active Low
than the maskable interrupts. It is always
recognized at the end of an instruction,
regardless of the state of the interrupt
enable control bits. This input includes a
Schmitt trigger to allow RC rise times.
53
BUSREQ
Bus Request
Input, Active Low
External devices can request the eZ80L92
MCU to release the memory interface bus
for their use, by driving this pin Low.
54
BUSACK
Bus
Acknowledge
Output, Active Low
The eZ80L92 MCU responds to a Low on
BUSREQ, by tristating the address, data,
and control signals, and by driving the
BUSACK line Low. During bus
acknowledge cycles ADDR[23:0], IORQ,
and MREQ are inputs.
55
HALT_SLP
HALT and
SLEEP
Indicator
Output, Active Low
A Low on this pin indicates that the CPU
has entered either HALT or SLEEP mode
because of execution of either a HALT or
SLP instruction.
56
VDD
Power Supply
Power Supply.
57
VSS
Ground
Ground.
58
RTC_XIN
Real-Time
Clock Crystal
Input
59
RTC_XOUT Real-Time
Clock Crystal
Output
60
RTC_VDD
Real-Time
Clock Power
Supply
Power supply for the Real-Time Clock and
associated 32 kHz oscillator. Isolated from
the power supply to the remainder of the
chip. A battery can be connected to this
pin to supply constant power to the
Real-Time Clock and 32 kHz oscillator.
61
VSS
Ground
Ground.
62
TMS
JTAG Test
Mode Select
PS013014-0107
Description
Input
This pin is the input to the low-power
32 kHz crystal oscillator for the Real-Time
Clock.
Bidirectional
This pin is the output from the low-power
32 kHz crystal oscillator for the Real-Time
Clock. This pin is an input when the RTC
is configured to operate from 50/60 Hz
input clock signals and the 32 kHz crystal
oscillator is disabled.
Input
JTAG Mode Select Input.
Architectural Overview
eZ80L92 MCU
Product Specification
13
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
63
TCK
JTAG Test
Clock
Input
JTAG and ZDI clock input.
64
TRIGOUT
JTAG Test
Output
Trigger Output
Active High trigger event indicator.
65
TDI
JTAG Test
Data In
Bidirectional
JTAG data input pin. Functions as
ZDI data I/O pin when JTAG is disabled.
66
TDO
JTAG Test
Data Out
Output
JTAG data output pin.
67
VDD
Power Supply
68
PD0
GPIO Port D
TxD0
UART
Output
Transmit Data
This pin is used by the UART to transmit
asynchronous serial data. This signal is
multiplexed with PD0.
IR_TXD
IrDA Transmit
Data
Output
This pin is used by the IrDA encoder/
decoder to transmit serial data. This signal
is multiplexed with PD0.
PD1
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
RxD0
Receive Data
Input
This pin is used by the UART to receive
asynchronous serial data. This signal is
multiplexed with PD1.
IR_RXD
IrDA Receive
Data
Input
This pin is used by the IrDA encoder/
decoder to receive serial data. This signal
is multiplexed with PD1.
69
PS013014-0107
Power Supply.
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
Architectural Overview
eZ80L92 MCU
Product Specification
14
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
70
PD2
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
RTS0
Request to
Send
Output, Active Low
Modem control signal from UART.
This signal is multiplexed with PD2.
PD3
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
CTS0
Clear to Send
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PD3.
PD4
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
DTR0
Data Terminal Output, Active Low
Ready
Modem control signal to the UART.
This signal is multiplexed with PD4.
PD5
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
DSR0
Data Set
Ready
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PD5.
71
72
73
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
15
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
74
PD6
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
DCD0
Data Carrier
Detect
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PD6.
PD7
GPIO Port D
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port D pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port D is multiplexed with
one UART.
RI0
Ring Indicator
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PD7.
PC0
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
TxD1
Transmit Data Output
75
76
PS013014-0107
This pin is used by the UART to transmit
asynchronous serial data. This signal is
multiplexed with PC0.
Architectural Overview
eZ80L92 MCU
Product Specification
16
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
77
PC1
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
RxD1
Receive Data
Input
This pin is used by the UART to receive
asynchronous serial data. This signal is
multiplexed with PC1.
PC2
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
RTS1
Request to
Send
Output, Active Low
Modem control signal from UART.
This signal is multiplexed with PC2.
PC3
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
CTS1
Clear to Send
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PC3.
78
79
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
17
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
80
PC4
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
DTR1
Data Terminal Output, Active Low
Ready
Modem control signal to the UART.
This signal is multiplexed with PC4.
PC5
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
DSR1
Data Set
Ready
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PC5.
PC6
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
DCD1
Data Carrier
Detect
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PC6.
PC7
GPIO Port C
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port C pin,
when programmed as output, can be
selected to be an open-drain or opensource output. Port C is multiplexed with
one UART.
RI1
Ring Indicator
Input, Active Low
Modem status signal to the UART.
This signal is multiplexed with PC7.
81
82
83
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
18
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
84
VSS
Ground
Ground.
85
XIN
System Clock Input
Oscillator Input
This pin is the input to the onboard crystal
oscillator for the primary system clock.
If an external oscillator is used, its clock
output should be connected to this pin.
When a crystal is used, it should be
connected between XIN and XOUT.
86
XOUT
System Clock
Oscillator
Output
This pin is the output of the onboard
crystal oscillator. When used, a crystal
should be connected between XIN and
XOUT.
87
VDD
Power Supply
88
PB0
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or opensource output.
T0_IN
Timer 0 In
Input
Alternate clock source for Programmable
Reload Timers 0 and 2. This signal is
multiplexed with PB0.
PB1
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or opensource output.
T1_IN
Timer 1 In
Input
Alternate clock source for Programmable
Reload Timers 1 and 3. This signal is
multiplexed with PB1.
89
PS013014-0107
Signal Direction
Output
Description
Power Supply.
Architectural Overview
eZ80L92 MCU
Product Specification
19
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
90
PB2
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or
open-source output.
SS
Slave Select
Input, Active Low
The slave select input line is used to
select a slave device in SPI mode.
This signal is multiplexed with PB2.
PB3
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or opensource output.
SCK
SPI Serial
Clock
Bidirectional
SPI serial clock. This signal is multiplexed
with PB3.
PB4
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or opensource output.
T4_OUT
Timer 4 Out
Output
Programmable Reload Timer 4 timer-out
signal. This signal is multiplexed with PB4.
PB5
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or
open-source output.
T5_OUT
Timer 5 Out
Output
Programmable Reload Timer 5 timer-out
signal. This signal is multiplexed with PB5.
91
92
93
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
20
Table 1. 100-Pin LQFP Pin Identification of eZ80L92 MCU (Continued)
Pin No
Symbol
Function
Signal Direction
Description
94
PB6
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or
open-source output.
MISO
Master In
Slave Out
Bidirectional
The MISO line is configured as an input
when the eZ80L92 MCU is an SPI master
device and as an output when eZ80L92
MCU is an SPI slave device. This signal is
multiplexed with PB6.
PB7
GPIO Port B
Bidirectional
This pin can be used for GPIO. It can be
individually programmed as input or
output and can also be used individually
as an interrupt input. Each Port B pin,
when programmed as output, can be
selected to be an open-drain or
open-source output.
MOSI
Master Out
Slave In
Bidirectional
The MOSI line is configured as an output
when the eZ80L92 MCU is an SPI master
device and as an input when the eZ80L92
MCU is an SPI slave device. This signal is
multiplexed with PB7.
96
VDD
Power Supply
Power Supply.
97
VSS
Ground
Ground.
98
SDA
I2C Serial Data Bidirectional
This pin carries the I2C data signal.
99
SCL
I2C Serial
Clock
Bidirectional
This pin is used to receive and transmit
the I2C clock.
100
PHI
System Clock
Output
This pin is an output driven by the internal
system clock.
95
PS013014-0107
Architectural Overview
eZ80L92 MCU
Product Specification
21
Pin Characteristics
Table 2 describes the characteristics of each pin in the eZ80L92 MCU’s 100-pin LQFP
package.
Table 2. Pin Characteristics of eZ80L92 MCU
Symbol
1
ADDR0
I/O
O
N/A
Yes
No
No
No
2
ADDR1
I/O
O
N/A
Yes
No
No
No
3
ADDR2
I/O
O
N/A
Yes
No
No
No
4
ADDR3
I/O
O
N/A
Yes
No
No
No
5
ADDR4
I/O
O
N/A
Yes
No
No
No
6
ADDR5
I/O
O
N/A
Yes
No
No
No
7
VDD
8
VSS
9
ADDR6
I/O
O
N/A
Yes
No
No
No
10
ADDR7
I/O
O
N/A
Yes
No
No
No
11
ADDR8
I/O
O
N/A
Yes
No
No
No
12
ADDR9
I/O
O
N/A
Yes
No
No
No
13
ADDR10
I/O
O
N/A
Yes
No
No
No
14
ADDR11
I/O
O
N/A
Yes
No
No
No
15
ADDR12
I/O
O
N/A
Yes
No
No
No
16
ADDR13
I/O
O
N/A
Yes
No
No
No
17
ADDR14
I/O
O
N/A
Yes
No
No
No
18
VDD
19
VSS
20
ADDR15
I/O
O
N/A
Yes
No
No
No
21
ADDR16
I/O
O
N/A
Yes
No
No
No
22
ADDR17
I/O
O
N/A
Yes
No
No
No
23
ADDR18
I/O
O
N/A
Yes
No
No
No
24
ADDR19
I/O
O
N/A
Yes
No
No
No
PS013014-0107
Reset
Active
Direction Direction Low/High
Tristate
Pull
Output Up/Down
Schmitt
Trigger
Open
Input Drain/Source
Pin
No.
Architectural Overview
eZ80L92 MCU
Product Specification
22
Table 2. Pin Characteristics of eZ80L92 MCU (Continued)
Symbol
25
ADDR20
I/O
O
N/A
Yes
No
No
No
26
ADDR21
I/O
O
N/A
Yes
No
No
No
27
ADDR22
I/O
O
N/A
Yes
No
No
No
28
ADDR23
I/O
O
N/A
Yes
No
No
No
29
CS0
O
O
Low
No
No
No
No
30
CS1
O
O
Low
No
No
No
No
31
CS2
O
O
Low
No
No
No
No
32
CS3
O
O
Low
No
No
No
No
33
VDD
34
VSS
35
DATA0
I/O
I
N/A
Yes
No
No
No
36
DATA1
I/O
I
N/A
Yes
No
No
No
37
DATA2
I/O
I
N/A
Yes
No
No
No
38
DATA3
I/O
I
N/A
Yes
No
No
No
39
DATA4
I/O
I
N/A
Yes
No
No
No
40
DATA5
I/O
I
N/A
Yes
No
No
No
41
DATA6
I/O
I
N/A
Yes
No
No
No
42
DATA7
I/O
I
N/A
Yes
No
No
No
43
VDD
44
VSS
45
IORQ
I/O
O
Low
Yes
No
No
No
46
MREQ
I/O
O
Low
Yes
No
No
No
47
RD
O
O
Low
No
No
No
No
48
WR
O
O
Low
No
No
No
No
49
INSTRD
O
O
Low
No
No
No
No
50
WAIT
I
I
Low
N/A
No
No
N/A
51
RESET
I
I
Low
N/A
Up
Yes
N/A
52
NMI
I
I
Low
N/A
No
Yes
N/A
PS013014-0107
Reset
Active
Direction Direction Low/High
Tristate
Pull
Output Up/Down
Schmitt
Trigger
Open
Input Drain/Source
Pin
No.
Architectural Overview
eZ80L92 MCU
Product Specification
23
Table 2. Pin Characteristics of eZ80L92 MCU (Continued)
Symbol
53
BUSREQ
I
I
Low
N/A
No
No
N/A
54
BUSACK
O
O
Low
No
No
No
No
55
HALT_SLP
O
O
Low
No
No
No
No
56
VDD
57
VSS
58
RTC_XIN
I
I
N/A
N/A
No
No
N/A
59
RTC_XOUT
I/O
U
N/A
N/A
No
No
No
60
RTC_VDD
61
VSS
62
TMS
I
I
N/A
N/A
Up
No
N/A
63
TCK
I
I
Rising (In)
Falling
(Out)
N/A
Up
No
N/A
64
TRIGOUT
I/O
O
High
Yes
No
No
No
65
TDI
I/O
I
N/A
Yes
Up
No
No
66
TDO
O
O
N/A
Yes
No
No
No
67
VDD
68
PD0
I/O
I
N/A
Yes
No
No
OD and OS
69
PD1
I/O
I
N/A
Yes
No
No
OD and OS
70
PD2
I/O
I
N/A
Yes
No
No
OD and OS
71
PD3
I/O
I
N/A
Yes
No
No
OD and OS
72
PD4
I/O
I
N/A
Yes
No
No
OD and OS
73
PD5
I/O
I
N/A
Yes
No
No
OD and OS
74
PD6
I/O
I
N/A
Yes
No
No
OD and OS
75
PD7
I/O
I
N/A
Yes
No
No
OD and OS
76
PC0
I/O
I
N/A
Yes
No
No
OD and OS
77
PC1
I/O
I
N/A
Yes
No
No
OD and OS
78
PC2
I/O
I
N/A
Yes
No
No
OD and OS
79
PC3
I/O
I
N/A
Yes
No
No
OD and OS
PS013014-0107
Reset
Active
Direction Direction Low/High
Tristate
Pull
Output Up/Down
Schmitt
Trigger
Open
Input Drain/Source
Pin
No.
Architectural Overview
eZ80L92 MCU
Product Specification
24
Table 2. Pin Characteristics of eZ80L92 MCU (Continued)
Symbol
80
PC4
I/O
I
N/A
Yes
No
No
OD and OS
81
PC5
I/O
I
N/A
Yes
No
No
OD and OS
82
PC6
I/O
I
N/A
Yes
No
No
OD and OS
83
PC7
I/O
I
N/A
Yes
No
No
OD and OS
84
VSS
85
XIN
I
I
N/A
N/A
No
No
N/A
86
XOUT
O
O
N/A
No
No
No
No
87
VDD
88
PB0
I/O
I
N/A
Yes
No
No
OD and OS
89
PB1
I/O
I
N/A
Yes
No
No
OD and OS
90
PB2
I/O
I
N/A
Yes
No
No
OD and OS
91
PB3
I/O
I
N/A
Yes
No
No
OD and OS
92
PB4
I/O
I
N/A
Yes
No
No
OD and OS
93
PB5
I/O
I
N/A
Yes
No
No
OD and OS
94
PB6
I/O
I
N/A
Yes
No
No
OD and OS
95
PB7
I/O
I
N/A
Yes
No
No
OD and OS
96
VDD
97
VSS
98
SDA
I/O
I
N/A
Yes
Up
No
OD
99
SCL
I/O
I
N/A
Yes
Up
No
OD
100
PHI
O
O
N/A
Yes
No
No
No
PS013014-0107
Reset
Active
Direction Direction Low/High
Tristate
Pull
Output Up/Down
Schmitt
Trigger
Open
Input Drain/Source
Pin
No.
Architectural Overview
eZ80L92 MCU
Product Specification
25
Register Map
All on-chip peripheral registers are accessed in the I/O address space. All I/O operations
employ 16-bit addresses. The upper byte of the 24-bit address bus is undefined during all
I/O operations (ADDR[23:16] = UU). All I/O operations using 16-bit addresses within the
range 0080h–00FFh are routed to the on-chip peripherals. External I/O Chip Selects are
not generated if the address space programmed for the I/O Chip Selects overlaps the
0080h–00FFh address range.
Registers at unused addresses within the 0080h–00FFh range assigned to on-chip
peripherals are not implemented. Read access to such addresses returns unpredictable
values and Write access produces no effect. Table 3 lists the register map for the
ZLP12840 MCU.
Table 3. Register Map
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
Programmable Reload Counter/Timers
0080
TMR0_CTL
Timer 0 Control Register
00
R/W
82
0081
TMR0_DR_L
Timer 0 Data Register—Low Byte
00
R
84
TMR0_RR_L
Timer 0 Reload Register—Low Byte
00
W
85
TMR0_DR_H
Timer 0 Data Register—High Byte
00
R
84
TMR0_RR_H
Timer 0 Reload Register—High Byte
00
W
86
0083
TMR1_CTL
Timer 1 Control Register
00
R/W
82
0084
TMR1_DR_L
Timer 1 Data Register—Low Byte
00
R
84
TMR1_RR_L
Timer 1 Reload Register—Low Byte
00
W
85
TMR1_DR_H
Timer 1 Data Register—High Byte
00
R
84
TMR1_RR_H
Timer 1 Reload Register—High Byte
00
W
86
TMR2_CTL
Timer 2 Control Register
00
R/W
82
0082
0085
0086
Programmable Reload Counter/Timers
0087
0088
TMR2_DR_L
Timer 2 Data Register—Low Byte
00
R
84
TMR2_RR_L
Timer 2 Reload Register—Low Byte
00
W
85
TMR2_DR_H
Timer 2 Data Register—High Byte
00
R
84
TMR2_RR_H
Timer 2 Reload Register—High Byte
00
W
86
PS013015-0316
Register Map
eZ80L92 MCU
Product Specification
26
Table 3. Register Map (Continued)
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
0089
TMR3_CTL
Timer 3 Control Register
00
R/W
82
008A
TMR3_DR_L
Timer 3 Data Register—Low Byte
00
R
84
TMR3_RR_L
Timer 3 Reload Register—Low Byte
00
W
85
TMR3_DR_H
Timer 3 Data Register—High Byte
00
R
84
TMR3_RR_H
Timer 3 Reload Register—High Byte
00
W
86
008C
TMR4_CTL
Timer 4 Control Register
00
R/W
82
008D
TMR4_DR_L
Timer 4 Data Register—Low Byte
00
R
84
TMR4_RR_L
Timer 4 Reload Register—Low Byte
00
W
85
TMR4_DR_H
Timer 4 Data Register—High Byte
00
R
84
TMR4_RR_H
Timer 4 Reload Register—High Byte
00
W
86
008F
TMR5_CTL
Timer 5 Control Register
00
R/W
82
0090
TMR5_DR_L
Timer 5 Data Register—Low Byte
00
R
84
TMR5_RR_L
Timer 5 Reload Register—Low Byte
00
W
85
TMR5_DR_H
Timer 5 Data Register—High Byte
00
R
84
TMR5_RR_H
Timer 5 Reload Register—High Byte
00
W
86
TMR_ISS
Timer Input Source Select Register
00
R/W
87
00/20
R/W
75
XX
W
76
008B
008E
0091
0092
Watchdog Timer
0093
WDT_CTL
Watch-Dog Timer Control Register1
0094
WDT_RR
Watch-Dog Timer Reset Register
General-Purpose Input/Output Ports
009A
PB_DR
Port B Data Register2
XX
R/W
42
009B
PB_DDR
Port B Data Direction Register
FF
R/W
43
009C
PB_ALT1
Port B Alternate Register 1
00
R/W
43
009D
PB_ALT2
Port B Alternate Register 2
00
R/W
43
2
009E
PC_DR
Port C Data Register
XX
R/W
42
009F
PC_DDR
Port C Data Direction Register
FF
R/W
43
00A0
PC_ALT1
Port C Alternate Register 1
00
R/W
43
00A1
PC_ALT2
Port C Alternate Register 2
00
R/W
43
XX
2
42
00A2
PD_DR
PS013015-0316
Port D Data Register
R/W
Register Map
eZ80L92 MCU
Product Specification
27
Table 3. Register Map (Continued)
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
00A3
PD_DDR
Port D Data Direction Register
FF
R/W
43
00A4
PD_ALT1
Port D Alternate Register 1
00
R/W
43
00A5
PD_ALT2
Port D Alternate Register 2
00
R/W
43
Chip Select/Wait State Generator
00A8
CS0_LBR
Chip Select 0 Lower Bound Register
00
R/W
68
00A9
CS0_UBR
Chip Select 0 Upper Bound Register
FF
R/W
69
00AA
CS0_CTL
Chip Select 0 Control Register
E8
R/W
70
00AB
CS1_LBR
Chip Select 1 Lower Bound Register
00
R/W
68
00AC
CS1_UBR
Chip Select 1 Upper Bound Register
00
R/W
69
00AD
CS1_CTL
Chip Select 1 Control Register
00
R/W
70
00AE
CS2_LBR
Chip Select 2 Lower Bound Register
00
R/W
68
00AF
CS2_UBR
Chip Select 2 Upper Bound Register
00
R/W
69
00B0
CS2_CTL
Chip Select 2 Control Register
00
R/W
70
00B1
CS3_LBR
Chip Select 3 Lower Bound Register
00
R/W
68
Chip Select/Wait State Generator
00B2
CS3_UBR
Chip Select 3 Upper Bound Register
00
R/W
69
00B3
CS3_CTL
Chip Select 3 Control Register
00
R/W
70
Serial Peripheral Interface (SPI) Block
00B8
SPI_BRG_L
SPI Baud Rate Generator
Register—Low Byte
02
R/W
134
00B9
SPI_BRG_H
SPI Baud Rate Generator
Register—High Byte
00
R/W
135
00BA
SPI_CTL
SPI Control Register
04
R/W
135
00BB
SPI_SR
SPI Status Register
00
R
136
00BC
SPI_TSR
SPI Transmit Shift Register
XX
W
137
SPI_RBR
SPI Receive Buffer Register
XX
R
137
00
R/W
126
Infrared Encoder/Decoder Block
00BF
IR_CTL
PS013015-0316
Infrared Encoder/Decoder Control
Register Map
eZ80L92 MCU
Product Specification
28
Table 3. Register Map (Continued)
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
Universal Asynchronous Receiver/Transmitter 0 (UART0) Block
00C0
00C1
00C2
00C3
UART0_RBR
UART 0 Receive Buffer Register
XX
R
112
UART0_THR
UART 0 Transmit Holding Register
XX
W
111
UART0_BRG_L
UART 0 Baud Rate Generator
Register—Low Byte
02
R/W
110
UART0_IER
UART 0 Interrupt Enable Register
00
R/W
112
UART0_BRG_H
UART 0 Baud Rate Generator
Register—High Byte
00
R/W
110
UART0_IIR
UART 0 Interrupt Identification Register
01
R
113
UART0_FCTL
UART 0 FIFO Control Register
00
W
114
UART0_LCTL
UART 0 Line Control Register
00
R/W
115
Universal Asynchronous Receiver/Transmitter 0 (UART0) Block
00C4
UART0_MCTL
UART 0 Modem Control Register
00
R/W
117
00C5
UART0_LSR
UART 0 Line Status Register
60
R
118
00C6
UART0_MSR
UART 0 Modem Status Register
XX
R
120
00C7
UART0_SPR
UART 0 Scratch Pad Register
00
R/W
122
00C8
I2C_SAR
I2C Slave Address Register
00
R/W
152
00C9
I2C_XSAR
I2C Extended Slave Address Register
00
R/W
152
00CA
I2C_DR
I2C Data Register
00
R/W
153
00CB
I2C_CTL
I2C Control Register
00
R/W
154
I2C_SR
I2C Status Register
F8
R
155
I2C_CCR
I2C Clock Control Register
00
W
157
I2C_SRR
I2C Software Reset Register
XX
W
159
I2C Block
00CC
00CD
PS013015-0316
Register Map
eZ80L92 MCU
Product Specification
29
Table 3. Register Map (Continued)
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
Universal Asynchronous Receiver/Transmitter 1 (UART1) Block
00D0
UART1_RBR
UART 1 Receive Buffer Register
XX
R
112
UART1_THR
UART 1 Transmit Holding Register
XX
W
111
UART1_BRG_L
UART 1 Baud Rate Generator
Register—Low Byte
02
R/W
110
UART1_IER
UART 1 Interrupt Enable Register
00
R/W
112
UART1_BRG_H
UART 1 Baud Rate Generator
Register—High Byte
00
R/W
110
UART1_IIR
UART 1 Interrupt Identification Register
01
R
113
UART1_FCTL
UART 1 FIFO Control Register
00
W
114
00D3
UART1_LCTL
UART 1 Line Control Register
00
R/W
115
00D4
UART1_MCTL
UART 1 Modem Control Register
00
R/W
117
00D1
00D2
Universal Asynchronous Receiver/Transmitter 1 (UART1) Block
00D5
UART1_LSR
UART 1 Line Status Register
60
R/W
118
00D6
UART1_MSR
UART 1 Modem Status Register
XX
R/W
120
00D7
UART1_SPR
UART 1 Scratch Pad Register
00
R/W
122
Low-Power Control
00DB
CLK_PPD1
Clock Peripheral Power-Down Register 1
00
R/W
36
00DC
CLK_PPD2
Clock Peripheral Power-Down Register 2
00
R/W
37
Real-Time Clock
00E0
RTC_SEC
RTC Seconds Register3
XX
R/W
90
00E1
RTC_MIN
RTC Minutes Register
XX
R/W3
91
92
00E2
RTC_HRS
RTC Hours Register
XX
R/W3
00E3
RTC_DOW
RTC Day-of-the-Week Register
XX
R/W3
93
94
00E4
RTC_DOM
RTC Day-of-the-Month Register
XX
R/W3
00E5
RTC_MON
RTC Month Register
XX
R/W3
95
96
00E6
RTC_YR
RTC Year Register
XX
R/W3
00E7
RTC_CEN
RTC Century Register
XX
R/W3
97
00E8
RTC_ASEC
RTC Alarm Seconds Register
XX
R/W
98
PS013015-0316
Register Map
eZ80L92 MCU
Product Specification
30
Table 3. Register Map (Continued)
Address
(hex)
Mnemonic
Name
Reset
(hex)
CPU
Access
Page
No
00E9
RTC_AMIN
RTC Alarm Minutes Register
XX
R/W
99
00EA
RTC_AHRS
RTC Alarm Hours Register
XX
R/W
100
00EB
RTC_ADOW
RTC Alarm Day-of-the-Week Register
0X
R/W
101
00EC
RTC_ACTRL
RTC Alarm Control Register
00
R/W
102
00ED
RTC_CTRL
RTC Control Register4
x0xxxx00b/
x0xxxx10b
R/W
103
Chip Select Bus Mode Control
00F0
CS0_BMC
Chip Select 0 Bus Mode Control Register
02h
R/W
71
00F1
CS1_BMC
Chip Select 1 Bus Mode Control Register
02h
R/W
71
00F2
CS2_BMC
Chip Select 2 Bus Mode Control Register
02h
R/W
71
00F3
CS3_BMC
Chip Select 3 Bus Mode Control Register
02h
R/W
71
Notes
1. After an external pin reset, the Watchdog Timer Control register is reset to 00h. After a Watchdog Timer time-out
reset, the Watchdog Timer Control register is reset to 20h.
2. When the CPU reads this register, the current sampled value of the port is read.
3. Read-only if RTC is locked; Read/Write if RTC is unlocked.
4. After an external pin reset or a WDT reset, the RTC Control register is reset to x0xxxx00b. After an RTC Alarm
Sleep-Mode Recovery reset, the RTC Control register is reset to x0xxxx10b.
PS013015-0316
Register Map
eZ80L92 MCU
Product Specification
31
eZ80® CPU Core
Zilog’s eZ80® CPU is the first 8-bit microprocessor to support 16 MB linear addressing.
Each software module or task under a real-time executive or operating system can operate
in Z80 compatible (64 KB) mode or full 24-bit (16 MB) address mode.
The eZ80 CPU instruction set is a superset of the instruction sets for the Z80 and Z180
CPUs. Z80 and Z180 programs are executable on an eZ80 CPU with little or no
modification.
Features
The features of eZ80 CPU includes:
•
•
•
•
•
•
•
•
Code-compatible with Z80 and Z180 products.
24-bit linear address space.
Single-cycle instruction fetch.
Pipelined fetch, decode, and execute.
Dual Stack Pointers for ADL (24-bit) and Z80 (16-bit) memory modes.
24-bit CPU registers and arithmetic logic unit (ALU).
Debug support.
Non-maskable Interrupt (NMI) supporting 128 maskable vectored interrupts.
New and Improved Instructions
These new instructions are:
•
PS013015-0316
Four new block transfer instructions provide DMA-like operations for memory-to-I/O
and I/O-to-memory transfers:
– INDRX (input from I/O, decrement the memory address, leave the I/O address
unchanged, and repeat).
– INIRX (input from I/O, increment the memory address, leave the I/O address
unchanged, and repeat).
– OTDRX (output to I/O, decrement the memory address, leave the I/O address
unchanged, and repeat).
– OTIRX (output to I/O, increment the memory address, leave the I/O address
unchanged, and repeat).
eZ80® CPU Core
eZ80L92 MCU
Product Specification
32
•
Four other block transfer instructions are modified to improve performance related to
the eZ80190 device. These modified instructions are:
– IND2R (input from I/O, decrement the memory address, decrement the I/O
address, and repeat).
– INI2R (input from I/O, increment the memory address, increment the I/O address,
and repeat).
– OTD2R (output to I/O, decrement the memory address, decrement the I/O
address, and repeat).
– OTI2R (output to I/O, increment the memory address, increment the I/O address,
and repeat).
For more information on the eZ80 CPU, its instruction set, and eZ80 programming, refer
to the eZ80® CPU User Manual. For more information on the eZ80190, refer to the
eZ80190 Product Specification.
PS013015-0316
eZ80® CPU Core
eZ80L92 MCU
Product Specification
33
Reset
RESET Operation
The RESET controller within the ZLP12840 MCU provides a consistent system reset
(RESET) function for all type of resets that may affect the system. Following four events
can cause a RESET:
•
•
•
•
External RESET pin assertion.
Watchdog Timer (WDT) time-out when configured to generate a RESET.
Real time clock alarm with eZ80 CPU in low-power SLEEP mode.
Execution of a Debug RESET command.
During RESET, an internal RESET mode timer holds the system in RESET for
257 system clock (SCLK) cycles. The RESET mode timer begins incrementing on the
next rising edge of SCLK following deactivation of all RESET events (RESET pin, WDT,
real time clock, and Debugger)
Note: You must determine if 257 SCLK cycles provides sufficient time for the primary crystal
oscillator to stabilize.
RESET, through the external RESET pin, must always be executed following application
of power (VDD ramp). Without the RESET, following power-up, proper operation of the
ZLP12840 cannot be guaranteed.
PS013015-0316
Reset
eZ80L92 MCU
Product Specification
34
Low-Power Modes
The ZLP12840 MCU provides a range of power-saving features. The highest level of
power reduction is provided by SLEEP mode. The next level of power reduction is provided by the HALT instruction. The lowest level of power reduction is provided by the
clock peripheral power-down registers.
SLEEP Mode
Execution of the eZ80 CPU’s SLP instruction places the ZLP12840 MCU into SLEEP
mode. In SLEEP mode, the operating characteristics are:
•
•
•
•
•
Primary crystal oscillator is disabled.
System clock is disabled.
eZ80 CPU is idle.
Program counter (PC) stops incrementing.
32 kHz crystal oscillator continues to operate and drives the Real-Time Clock and the
Watchdog Timer (if WDT is configured to operate from the 32 kHz oscillator.)
The eZ80 CPU can be brought out of SLEEP mode by any of the following operations:
•
•
•
RESET through the external RESET pin driven Low.
•
RESET through execution of a Debug RESET command.
RESET through a Real-Time Clock alarm.
RESET through a Watchdog Timer time-out (if running off of the 32 kHz oscillator and
configured to generate a RESET upon time-out).
After exiting SLEEP mode, the standard RESET delay occurs to allow the primary crystal
oscillator to stabilize. See Reset on page 33.
HALT Mode
Execution of the eZ80 CPU’s HALT instruction places the ZLP12840 MCU into HALT
mode. In HALT mode, the operating characteristics are:
•
•
•
•
PS013015-0316
Primary crystal oscillator is enabled and continues to operate.
System clock is enabled and continues to operate.
eZ80 CPU is idle.
Program counter stops incrementing.
Low-Power Modes
eZ80L92 MCU
Product Specification
35
The eZ80 CPU can be brought out of HALT mode by any of the following operations:
•
•
•
•
Non-maskable interrupt (NMI).
•
RESET through execution of a Debug RESET command.
Maskable interrupt.
RESET through the external RESET pin driven Low.
Watchdog Timer time-out (if configured to generate either an NMI or RESET upon
time-out).
To minimize current in HALT mode, the system clock must be disabled for all unused onchip peripherals through the Clock Peripheral Power-Down Registers.
Clock Peripheral Power-Down Registers
To reduce power, the Clock Peripheral Power-Down Registers allow the system clock to
be disabled to unused on-chip peripherals. On RESET, all peripherals are enabled. The
clock to unused peripherals can be disabled by setting the appropriate bit in the Clock
Peripheral Power-Down Registers to 1. When powered down, the peripherals are completely disabled. To re-enable, the bit in the Clock Peripheral Power-Down Registers must
be cleared to 0.
Many peripherals feature separate enable/disable control bits that must be appropriately
set for operation. These peripheral specific enable/disable bits do not provide the same
level of power reduction as the Clock Peripheral Power-Down Registers. When powered
down, the standard peripheral control registers are not accessible for Read or Write access.
See Table 4 and Table 5.
PS013015-0316
Low-Power Modes
eZ80L92 MCU
Product Specification
36
Table 4. Clock Peripheral Power-Down Register 1 (CLK_PPD1 = 00DBh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write; R = Read Only.
Bit Position
7
GPIO_D_OFF
6
GPIO_C_OFF
5
GPIO_B_OFF
Value
1
System clock to GPIO Port D is powered down.
Port D alternate functions do not operate correctly.
0
System clock to GPIO Port D is powered up.
1
System clock to GPIO Port C is powered down.
Port C alternate functions do not operate correctly.
0
System clock to GPIO Port C is powered up.
1
System clock to GPIO Port B is powered down.
Port B alternate functions do not operate correctly.
0
System clock to GPIO Port B is powered up.
4
PS013015-0316
Description
Reserved.
3
SPI_OFF
1
System clock to SPI is powered down.
0
System clock to SPI is powered up.
2
I2C_OFF
1
System clock to I2C is powered down.
0
System clock to I2C is powered up.
1
UART1_OFF
1
System clock to UART1 is powered down.
0
System clock to UART1 is powered up.
0
UART0_OFF
1
System clock to UART0 and IrDA endec is powered down.
0
System clock to UART0 and IrDA endec is powered up.
Low-Power Modes
eZ80L92 MCU
Product Specification
37
Table 5. Clock Peripheral Power-Down Register 2 (CLK_PPD2 = 00DCh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write; R = Read Only.
Bit Position
PS013015-0316
Value
Description
7
PHI_OFF
1
PHI Clock output is disabled (output is high-impedance).
0
PHI Clock output is enabled.
6
0
Reserved.
5
PRT5_OFF
1
System clock to PRT5 is powered down.
0
System clock to PRT5 is powered up.
4
PRT4_OFF
1
System clock to PRT4 is powered down.
0
System clock to PRT4 is powered up.
3
PRT3_OFF
1
System clock to PRT3 is powered down.
0
System clock to PRT3 is powered up.
2
PRT2_OFF
1
System clock to PRT2 is powered down.
0
System clock to PRT2 is powered up.
1
PRT1_OFF
1
System clock to PRT1 is powered down.
0
System clock to PRT1 is powered up.
0
PRT0_OFF
1
System clock to PRT0 is powered down.
0
System clock to PRT0 is powered up.
Low-Power Modes
eZ80L92 MCU
Product Specification
38
General-Purpose Input/Output
The ZLP12840 MCU features 24 General-Purpose Input/Output (GPIO) pins. The GPIO
pins are assembled as three 8-bit ports — Port B, Port C, and Port D. All port signals can
be configured for use as either inputs or outputs. In addition, all the port pins can be used
as vectored interrupt sources for the eZ80 CPU.
GPIO Operation
The GPIO operation is same for all 3 GPIO ports (Ports B, C, and D). Each port features
eight GPIO port pins. The operating mode for each pin is controlled by four bits that are
divided between four 8-bit registers. These GPIO mode control registers are:
•
•
•
•
Port x Data Register (Px_DR)
Port x Data Direction Register (Px_DDR)
Port x Alternate Register 1 (Px_ALT1)
Port x Alternate Register 2 (Px_ALT2)
where x is B, C, or D representing any of the three GPIO ports B, C, or D. The mode for
each pin is controlled by setting each register bit pertinent to the pin to be configured. For
example, the operating mode for Port B Pin 7 (PB7), is set by the values contained in
PB_DR[7], PB_DDR[7], PB_ALT1[7], and PB_ALT2[7].
The combination of the GPIO control register bits allows individual configuration of each
port pin for nine modes. In all modes, reading of the Port x Data register returns the
sampled state, or level, of the signal on the corresponding pin. Table 6 lists the function of
each port signal based upon these four register bits. After a RESET event, all GPIO port
pins are configured as standard digital inputs, with interrupts disabled.
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
39
Table 6. GPIO Mode Selection
GPIO
Mode
1
Px_ALT2
Bits7:0
Px_ALT1 Px_DDR Px_DR
Bits7:0
Bits7:0 Bits7:0 Port Mode
Output
0
0
0
0
Output
0
0
0
0
1
Output
1
0
0
1
0
Input from pin
High impedance
0
0
1
1
Input from pin
High impedance
0
1
0
0
Open-Drain output
0
0
1
0
1
Open-Drain I/O
High impedance
0
1
1
0
Open source I/O
High impedance
0
1
1
1
Open source output
1
5
1
0
0
0
Reserved
High impedance
6
1
0
0
1
Interrupt—dual edge triggered
High impedance
7
1
0
1
0
Port B, C, or D—alternate function controls port I/O.
1
0
1
1
Port B, C, or D—alternate function controls port I/O.
1
1
0
0
Interrupt—active Low
High impedance
1
1
0
1
Interrupt—active High
High impedance
1
1
1
0
Interrupt—falling edge triggered
High impedance
1
1
1
1
Interrupt—rising edge triggered
High impedance
2
3
4
8
9
GPIO Mode 1. This port pin is configured as a standard digital output pin. The value
written to the Port x Data register (Px_DR) is located on the pin.
GPIO Mode 2. The port pin is configured as a standard digital input pin. The output is
tristated (high impedance). The value stored in the Port x Data register produces no effect.
As in all modes, a Read from the Port x Data register returns the pin’s value. GPIO Mode
2 is the default operating mode following a RESET.
GPIO Mode 3. The port pin is configured as open-drain I/O. The GPIO pins do not feature
an internal pull-up to the supply voltage. To employ the GPIO pin in OPEN-DRAIN
mode, an external pull-up resistor must connect the pin to the supply voltage. Writing a 0
to the Port x Data register outputs a Low at the pin. Writing a 1 to the Port x Data register
results in high-impedance output.
GPIO Mode 4. The port pin is configured as open-source I/O. The GPIO pins do not
feature an internal pull-down to the supply ground. To employ the GPIO pin in OPENSOURCE mode, an external pull-down resistor must connect the pin to the supply ground.
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
40
Writing a 1 to the Port x Data register outputs a High at the pin. Writing a 0 to the Port x
Data register results in a high-impedance output.
GPIO Mode 5. Reserved. This pin generates high-impedance output.
GPIO Mode 6. This bit enables a dual edge-triggered interrupt mode. Both rising and fall-
ing edge on the pin cause an interrupt request to be sent to the eZ80® CPU. Writing 1 to
the Port x Data register bit position resets the corresponding interrupt request. Writing 0
produces no effect. You must set the Port x Data register prior to entering the edgetriggered interrupt mode.
GPIO Mode 7. For Ports B, C, and D, this port pin is configured to pass control over to the
alternate (secondary) functions assigned to the pin. For example, the alternate mode
function for PC7 is RI1 and the alternate mode function for PB4 is the Timer 4 Out. When
GPIO Mode 7 is enabled, the pin output data and pin tristated control come from the
alternate function's data output and tristate control, respectively. The value in the Port x
Data register has no effect on operation.
Note: Input signals are sampled by the system clock before being passed to the alternate
function input.
GPIO Mode 8. The port pin is configured for level-sensitive interrupt modes. An interrupt
request is generated when the level at the pin is the same as the level stored in the Port x
Data register. The port pin value is sampled by the system clock. The input pin must be
held at the selected interrupt level for a minimum of 2 clock periods to initiate an interrupt.
The interrupt request remains active as long as this condition is maintained at the external
source.
GPIO Mode 9. The port pin is configured for single edge-triggered interrupt mode. The
value in the Port x Data register determines if a positive or negative edge causes an
interrupt request. A 0 in the Port x Data register bit sets the selected pin to generate an
interrupt request for falling edges. A 1 in the Port x Data register bit sets the selected pin to
generate an interrupt request for rising edges. The interrupt request remains active until a 1
is written to the corresponding interrupt request of the Port x Data register bit. Writing a 0
produces no effect on operation. You must set the Port x Data register before entering the
edge-triggered interrupt mode.
A simplified block diagram of a GPIO port pin is illustrated in Figure 3.
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
41
GPIO Register
Data (Input)
Q
D
Q
D
System Clock
VDD
Mode 1
Mode 4
Data Bus
D
Q
Port
Pin
System Clock
GPIO Register
Data (Output)
Mode 1
GND
Mode 3
Figure 3. GPIO Port Pin Block Diagram
GPIO Interrupts
Each port pin can be used as an interrupt source. Interrupts are either level-triggered or
edge-triggered.
Level-Triggered Interrupts
When the port is configured for level-triggered interrupts, the corresponding port pin is
tristated. An interrupt request is generated when the level at the pin is the same as the level
stored in the Port x Data register. The port pin value is sampled by the system clock. The
input pin must be held at the selected interrupt level for a minimum of 2 consecutive clock
cycles to initiate an interrupt. The interrupt request remains active as long as this condition
is maintained at the external source.
For example, if PD3 is programmed for low-level interrupt and the pin is forced Low for
2 consecutive clock cycles, an interrupt request signal is generated from that port pin and
sent to the eZ80 CPU. The interrupt request signal remains active until the external device
driving PD3 forces the pin High.
Edge-Triggered Interrupts
When the port is configured for edge-triggered interrupts, the corresponding port pin is
tristated. If the pin receives the correct edge from an external device, the port pin generates
an interrupt request signal to the eZ80 CPU. Any time a port pin is configured for
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
42
edge-triggered interrupt, writing a 1 to that pin’s Port x Data register causes a reset of the
edge-detected interrupt. You must set the bit in the Port x Data register to 1 before entering
either single or dual edge-triggered interrupt mode for that port pin.
When configured for dual edge-triggered interrupt mode (GPIO Mode 6), both a rising
and a falling edge on the pin cause an interrupt request to be sent to the eZ80 CPU.
When configured for single edge-triggered interrupt mode (GPIO Mode 9), the value in
the Port x Data register determines if a positive or negative edge causes an interrupt
request. A 0 in the Port x Data register bit sets the selected pin to generate an interrupt
request for falling edges. A 1 in the Port x Data register bit sets the selected pin to generate
an interrupt request for rising edges.
GPIO Control Registers
The 12 GPIO Control Registers operate in groups of four with a set for each Port (Ports B,
C, and D). Each GPIO port features a Port Data register, Port Data Direction register, Port
Alternate register 1, and Port Alternate register 2.
Port x Data Registers
When the port pins are configured for one of the output modes, the data written to the
Port x Data Registers (see Table 7) are driven on the corresponding pins. In all modes,
reading from the Port x Data registers always returns the current sampled value of the
corresponding pins. When the port pins are configured as edge-triggered interrupt sources,
writing 1 to the corresponding bit in the Port x Data register clears the interrupt signal that
is sent to the eZ80 CPU. When the port pins are configured for edge-selectable interrupts
or level-sensitive interrupts, the value written to the Port x Data register bit selects the
interrupt edge or interrupt level. See Table 6.
Table 7. Port x Data Registers (PB_DR = 009Ah, PC_DR = 009Eh, PD_DR =
00A2h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: X = Undefined; R/W = Read/Write.
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
43
Port x Data Direction Registers
In addition to the other GPIO Control Registers, the Port x Data Direction Registers (see
Table 8) control the operating modes of the GPIO port pins. See Table 6.
Table 8. Port x Data Direction Registers (PB_DDR = 009Bh, PC_DDR =
009Fh, PD_DDR = 00A3h)
Bit
7
6
5
4
3
2
1
0
Reset
1
1
1
1
1
1
1
1
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Port x Alternate Register 1
In addition to other GPIO Control Registers, the Port x Alternate Register 1 (see Table 9)
control the operating modes of the GPIO port pins. See Table 6.
Table 9. Port x Alternate Registers 1 (PB_ALT1 = 009Ch, PC_ALT1 = 00A0h,
PD_ALT1 = 00A4h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Port x Alternate Register 2
In addition to other GPIO Control Registers, the Port x Alternate Register 2 (see Table 10)
control the operating modes of the GPIO port pins. See Table 6.
Table 10. Port x Alternate Registers 2 (PB_ALT2 = 009Dh, PC_ALT2 =
00A1h, PD_ALT2 = 00A5h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
PS013015-0316
General-Purpose Input/Output
eZ80L92 MCU
Product Specification
44
Interrupt Controller
The interrupt controller on the ZLP12840 MCU routes the interrupt request signals from
the internal peripherals and external devices (through the GPIO pins) to the eZ80 CPU.
Maskable Interrupts
On the ZLP12840 MCU, all maskable interrupts use the eZ80 CPU’s vectored interrupt
function. Table 11 lists the low-byte vector for each of the maskable interrupt sources.
The maskable interrupt sources are listed in order of their priority, with vector 00h being
the highest-priority interrupt. The 16-bit interrupt vector is located at starting address
{I[7:0], IVECT[7:0]}, where I[7:0] is the eZ80 CPU’s Interrupt Page Address Register.
Table 11. Interrupt Vector Sources by Priority
Vector
Source
Vector
Source
Vector
Source
Vector
Source
00h
Unused
1Ah
UART 1
34h
Port B 2
4Eh
Port C 7
02h
Unused
1Ch
I2C
36h
Port B 3
50h
Port D 0
04h
Unused
1Eh
SPI
38h
Port B 4
52h
Port D 1
06h
Unused
20h
Unused
3Ah
Port B 5
54h
Port D 2
08h
Unused
22h
Unused
3Ch
Port B 6
56h
Port D 3
0Ah
PRT 0
24h
Unused
3Eh
Port B 7
58h
Port D 4
0Ch
PRT 1
26h
Unused
40h
Port C 0
5Ah
Port D 5
0Eh
PRT 2
28h
Unused
42h
Port C 1
5Ch
Port D 6
10h
PRT 3
2Ah
Unused
44h
Port C 2
5Eh
Port D 7
12h
PRT 4
2Ch
Unused
46h
Port C 3
60h
Unused
14h
PRT 5
2Eh
Unused
48h
Port C 4
62h
Unused
16h
RTC
30h
Port B 0
4Ah
Port C 5
64h
Unused
18h
UART 0
32h
Port B 1
4Ch
Port C 6
66h
Unused
Note: Absolute locations 00h, 08h, 10h, 18h, 20h, 28h, 30h, 38h, and 66h are reserved for hardware
reset, NMI, and RST instruction.
Your program must store the interrupt service routine starting address in the two-byte
interrupt vector locations. For example, for ADL mode the two-byte address for the SPI
interrupt service routine would be stored at {00h, I[7:0], 1Eh} and {00h, I[7:0], 1Fh}. In
Z80 mode, the two-byte address for the SPI interrupt service routine would be stored at
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{MBASE[7:0], I[7:0], 1Eh} and {MBASE, I[7:0], 1Fh}. The least significant byte is
stored at the lower address.
When any one or more of the interrupt requests (IRQs) become active, an interrupt request
is generated by the interrupt controller and sent to the CPU. The corresponding 8-bit
interrupt vector for the highest priority interrupt is placed on the 8-bit interrupt vector bus,
IVECT[7:0]. The interrupt vector bus is internal to the ZLP12840 and is therefore not
visible externally. The response time of the eZ80 CPU to an interrupt request is a
function of the current instruction being executed as well as the number of WAIT states
being asserted.
The interrupt vector, {I[7:0], IVECT[7:0]}, is visible on the address bus, ADDR[15:0],
when the interrupt service routine begins. The response of the eZ80 CPU to a vectored
interrupt on the ZLP12840 is explained in Table 12. Interrupt sources are required to be
active until the Interrupt Service Routine (ISR) starts. We recommend you to change the
Interrupt Page Address Register (I) value from its default value of 00h as this address can
create conflicts between the non-maskable interrupt vector, the RST instruction addresses,
and the maskable interrupt vectors.
Table 12. Vectored Interrupt Operation
Memory
Mode
Z80 Mode
ADL
Bit
0
MADL
Bit Operation
0
Read the LSB of the interrupt vector placed on the internal vectored
interrupt bus, IVECT [7:0], by the interrupting peripheral.
• IEF1 ← 0
• IEF2 ← 0
• The starting Program Counter is effectively {MBASE, PC[15:0]}.
• Push the 2-byte return address PC[15:0] on the ({MBASE,SPS}) stack.
• The ADL mode bit remains cleared to 0.
• The interrupt vector address is located at { MBASE, I[7:0], IVECT[7:0] }.
• PC[15:0] ← ( { MBASE, I[7:0], IVECT[7:0] } ).
• The ending Program Counter is effectively {MBASE, PC[15:0]}
• The interrupt service routine must end with RETI.
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Table 12. Vectored Interrupt Operation (Continued)
Memory
Mode
ADL Mode
ADL
Bit
1
MADL
Bit Operation
0
Read the LSB of the interrupt vector placed on the internal vectored
interrupt bus, IVECT [7:0], by the interrupting peripheral.
• IEF1 ← 0
• IEF2 ← 0
• The starting Program Counter is PC[23:0].
• Push the 3-byte return address, PC[23:0], onto the SPL stack.
• The ADL mode bit remains set to 1.
• The interrupt vector address is located at { 00h, I[7:0], IVECT[7:0] }.
• PC[15:0] ← ( { 00h, I[7:0], IVECT[7:0] } ).
• The ending Program Counter is { 00h, PC[15:0] }.
• The interrupt service routine must end with RETI.
Z80 Mode
0
1
Read the LSB of the interrupt vector placed on the internal vectored
interrupt bus, IVECT[7:0], bus by the interrupting peripheral.
• IEF1 ← 0
• IEF2 ← 0
• The starting Program Counter is effectively {MBASE, PC[15:0]}.
• Push the 2-byte return address, PC[15:0], onto the SPL stack.
• Push a 00h byte onto the SPL stack to indicate an interrupt from Z80®
mode (because ADL = 0).
• Set the ADL mode bit to 1.
• The interrupt vector address is located at { 00h, I[7:0], IVECT[7:0] }.
• PC[15:0] ← ( { 00h, I[7:0], IVECT[7:0] } ).
• The ending Program Counter is { 00h, PC[15:0] }.
• The interrupt service routine must end with RETI.L
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Table 12. Vectored Interrupt Operation (Continued)
Memory
Mode
ADL Mode
ADL
Bit
1
MADL
Bit Operation
1
Read the LSB of the interrupt vector placed on the internal vectored
interrupt bus, IVECT [7:0], by the interrupting peripheral.
• IEF1 ← 0
• IEF2 ← 0
• The starting Program Counter is PC[23:0].
• Push the 3-byte return address, PC[23:0], onto the SPL stack.
• Push a 01h byte onto the SPL stack to indicate a restart from ADL mode
(because ADL = 1).
• The ADL mode bit remains set to 1.
• The interrupt vector address is located at {00h, I[7:0], IVECT[7:0]}.
• PC[15:0] ← ( { 00h, I[7:0], IVECT[7:0] } ).
• The ending Program Counter is { 00h, PC[15:0] }.
• The interrupt service routine must end with RETI.L
Non-maskable Interrupts
An active Low input on the NMI pin generates an interrupt request to the eZ80 CPU. This
non-maskable interrupt is always serviced by the eZ80 CPU, regardless of the state of the
Interrupt Enable flags (IEF1 and IEF2). The non-maskable interrupt is prioritized higher
than all maskable interrupts. The response of the eZ80 CPU to a non-maskable interrupt is
described in detail in eZ80® CPU User Manual (UM0077).
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Chip Selects and Wait States
The ZLP12840 MCU generates four Chip Selects for external devices. Each Chip Select is
programmed to access either memory space or I/O space. The Memory Chip Selects can
be individually programmed on a 64 KB boundary. Each I/O Chip Select can choose a
256-byte section of I/O space. In addition, each Chip Select can be programmed for up to
7 wait states.
Memory and I/O Chip Selects
Each of the Chip Selects is enabled for either the memory address space or the I/O address
space, but not both. To select the memory address space for a particular Chip Select,
CSx_IO (CSx_CTL[4]) must be reset to 0. To select the I/O address space for a particular
Chip Select, CSx_IO must be set to 1. After RESET, the default is for all Chip Selects to
be configured for the memory address space. For either the memory address space or the
I/O address space, the individual Chip Selects must be enabled by setting CSx_EN
(CSx_CTL[3]) to 1.
Memory Chip Select Operation
Operation of each Memory Chip Selects is controlled by three control registers. To enable
a particular Memory Chip Select, following conditions must be fulfilled:
•
•
•
The Chip Select is enabled by setting CSx_EN to 1.
The Chip Select is configured for Memory by clearing CSx_IO to 0.
The address is in the associated Chip Select range:
CSx_LBR[7:0] ≤ ADDR[23:16] ≤ CSx_UBR[7:0]
•
•
No higher priority (lower number) Chip Select meets the above conditions.
A memory access instruction must be executing.
If all the above conditions are met to generate a Memory Chip Select, then the following
actions occur:
•
•
•
The appropriate Chip Select—CS0, CS1, CS2, or CS3—is asserted (driven Low).
MREQ is asserted (driven Low).
Depending upon the instruction, either RD or WR is asserted (driven Low).
If the upper and lower bounds are set to the same value (CSx_UBR = CSx_LBR), then a
particular Chip Select is valid for a single 64 KB page.
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Memory Chip Select Priority
A lower-numbered Chip Select is given priority over a higher-numbered Chip Select. For
example, if the address space of Chip Select 0 overlaps the Chip Select 1 address space,
Chip Select 0 is active.
RESET States
On RESET, Chip Select 0 is active for all addresses, as its Lower Bound register resets to
00h and its Upper Bound register resets to FFh. All of the other Chip Select Lower and
Upper Bound registers reset to 00h.
Memory Chip Select Example
The use of Memory Chip Selects is illustrated in Figure 4. The associated control register
values are listed in Table 13. In this example, all 4 Chip Selects are enabled and
configured for memory addresses. Also, CS1 overlaps with CS0. As CS0 has the higher
than CS1, CS1 is not active for much of its defined address space.
Memory
Location
CS3_UBR = FFh
CS3_LBR = D0h
CS2_UBR = CFh
CS2_LBR = A0h
CS1_UBR = 9Fh
FFFFFFh
CS3 Active
3 MB Address Space
CS2 Active
3 MB Address Space
CS1 Active
2 MB Address Space
CS0_UBR = 7Fh
D00000h
CFFFFFh
A00000h
9FFFFFh
800000h
7FFFFFh
CS0 Active
8 MB Address Space
CS0_LBR = CS1_LBR = 00h
000000h
Figure 4. Memory Chip Select Example
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Table 13. Register Values for Memory Chip Select Example in Figure 4
Chip
CSx_CTL[3] CSx_CTL[4]
Select
CSx_EN
CSx_IO
CSx_LBR CSx_UBR Description
CS0
1
0
00h
7Fh
CS0 is enabled as a Memory Chip Select.
Valid addresses range from
000000h–7FFFFFh.
CS1
1
0
00h
9Fh
CS1 is enabled as a Memory Chip Select.
Valid addresses range from
800000h–9FFFFFh.
CS2
1
0
A0h
CFh
CS2 is enabled as a Memory Chip Select.
Valid addresses range from
A00000h–CFFFFFh.
CS3
1
0
D0h
FFh
CS3 is enabled as a Memory Chip Select.
Valid addresses range from
D00000h–FFFFFFh.
I/O Chip Select Operation
I/O Chip Selects are active when the CPU is performing I/O instructions. As the I/O space
is separate from the memory space in the ZLP12840 device, there can never be a conflict
between I/O and memory addresses.
The ZLP12840 MCU supports a 16-bit I/O address. The I/O Chip Select logic decodes the
High byte of the I/O address, ADDR[15:8]. Because the upper byte of the address bus,
ADDR[23:16], is ignored, the I/O devices is always accessed from within any memory
mode (ADL or Z80). The MBASE offset value used for setting the Z80 MEMORY mode
page is also always ignored.
Four I/O Chip Selects are available with the ZLP12840. To generate a particular I/O Chip
Select, the following conditions must be fulfilled:
•
•
•
•
•
The Chip Select is enabled by setting CSX_EN to 1.
The Chip Select is configured for I/O by setting CSx_IO to 1.
An I/O Chip Select address match occurs—ADDR[15:8] = CSx_LBR[7:0].
No higher-priority (lower-number) Chip Select meets the above conditions.
The I/O address is not within the on-chip peripheral address range 0080h–00FFh. Onchip peripheral registers assume priority for all addresses where:
0080h ≤ ADDR[15:0] ≤ 00FFh
•
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An I/O instruction must be executing.
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If all the above conditions are met to generate an I/O Chip Select, then the following
actions occur:
•
•
•
The appropriate Chip Select—CS0, CS1, CS2, or CS3—is asserted (driven Low).
IORQ is asserted (driven Low).
Depending upon the instruction, either RD or WR is asserted (driven Low).
WAIT States
For each of the Chip Selects, programmable WAIT states can be asserted to provide
external devices with additional clock cycles to complete their Read or Write operations.
The number of WAIT states for a particular Chip Select is controlled by the 3-bit field
CSx_WAIT (CSx_CTL[7:5]). The WAIT states can be independently programmed to
provide 0 to 7 WAIT states for each Chip Select. The WAIT states idle the CPU for the
specified number of system clock cycles.
WAIT Input Signal
Similar to the programmable WAIT states, an external peripheral drives the WAIT input
pin to force the CPU to provide additional clock cycles to complete its Read or Write operation. Driving the WAIT pin Low stalls the CPU. The CPU resumes operation on the first
rising edge of the internal system clock following de-assertion of the WAIT pin.
Caution:
If the WAIT pin is to be driven by an external device, the corresponding Chip Select for the
device must be programmed to provide at least one WAIT state. Due to input sampling of
the WAIT input pin (see Figure 5), one programmable WAIT state is required to allow the
external peripheral sufficient time to assert the WAIT pin. It is recommended that the corresponding Chip Select for the external device be programmed to provide the maximum
number of WAIT states (seven).
Wait
Pin
D
Q
eZ80
CPU
System Clock
Figure 5. Wait Input Sampling Block Diagram
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An example of WAIT state operation is illustrated in Figure 6. In this example, the Chip
Select is configured to provide a single WAIT state. The external peripheral being
accessed drives the WAIT pin Low to request assertion of an additional WAIT state. If the
WAIT pin is asserted for additional system clock cycles, WAIT states are added until the
WAIT pin is de-asserted (High).
TCLK
TCSx_WAIT
TWAIT
X IN
ADDR[23:0]
DATA[7:0]
(input)
CSx
MREQ
RD
INSTRD
WAIT
Figure 6. Wait State Operation Example (Read Operation)
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Chip Selects During Bus Request/Bus Acknowledge Cycles
When the CPU relinquishes the address bus to an external peripheral in response to an
external bus request (BUSREQ), it drives the bus acknowledge pin (BUSACK) Low. The
external peripheral then drives the address bus (and data bus). The CPU continues to generate Chip Select signals in response to the address on the bus. External devices cannot
access the internal registers of the ZLP12840 MCU.
Bus Mode Controller
The bus mode controller allows the address and data bus timing and signal formats of the
ZLP12840 to be configured to connect seamlessly with external eZ80, Z80, Intel-, or
Motorola-compatible devices. Bus modes for each of the chip selects can be configured
independently using the Chip Select Bus Mode Control Registers. The number of eZ80
system clock cycles per bus mode state is also independently programmable. For Intel bus
mode, multiplexed address and data can be selected in which the lower byte of the address
and the data byte both use the data bus, DATA[7:0]. Each of the bus modes is explained in
more detail in the following sections.
eZ80® Bus Mode
Chip selects configured for eZ80 Bus Mode do not modify the bus signals from the CPU.
The timing diagrams for external Memory and I/O Read and Write operations are shown
in the AC Characteristics on page 203. The default mode for each chip select is eZ80s
mode.
Z80® Bus Mode
Chip selects configured for Z80 mode modify the Z80 bus signals to match the Z80
microprocessor address and data bus interface signal format and timing. During Read
operations, the Z80 Bus Mode employs three states (T1, T2, and T3) as described in
Table 14.
Table 14. Z80® Bus Mode Read States
STATE T1
The Read cycle begins in State T1. The CPU drives the address onto the address bus and
the associated Chip Select signal is asserted.
STATE T2
During State T2, the RD signal is asserted. Depending upon the instruction, either the
MREQ or IORQ signal is asserted. If the external WAIT pin is driven Low at least one eZ80
system clock cycle prior to the end of State T2, additional WAIT states (TWAIT) are asserted
until the WAIT pin is driven High.
STATE T3
During State T3, no bus signals are altered. The data is latched by the ZLP12840 at the
rising edge of the eZ80 system clock at the end of State T3.
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During Write operations, Z80 Bus Mode employs 3 states (T1, T2, and T3) as described in
Table 15.
Table 15. Z80® Bus Mode Write States
STATE T1
The Write cycle begins in State T1. The CPU drives the address onto the address bus, the
associated Chip Select signal is asserted.
STATE T2
During State T2, the WR signal is asserted. Depending upon the instruction, either the
MREQ or IORQ signal is asserted. If the external WAIT pin is driven Low at least one eZ80
system clock cycle prior to the end of State T2, additional WAIT states (TWAIT) are asserted
until the WAIT pin is driven High.
STATE T3
During State T3, no bus signals are altered.
Z80 Bus Mode Read and Write timing is illustrated in Figure 7 and Figure 8. The Z80 Bus
Mode states can be configured for 1 to 15 eZ80 system clock cycles. In these figures, each
Z80 Bus Mode state is two eZ80 system clock cycles in duration. Figure 7 and Figure 8
also illustrate the assertion of 1 WAIT state (TWAIT) by the external peripheral during each
Z80 Bus Mode cycle.
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T1
T2
TCLK
T3
System Clock
ADDR[23:0]
DATA[7:0]
CSx
RD
WAIT
WR
MREQ
or IORQ
Figure 7. Z80® Bus Mode Read Timing Example
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T1
T2
TCLK
T3
System Clock
ADDR[23:0]
DATA[7:0]
CSx
RD
WAIT
WR
MREQ
or IORQ
Figure 8. Z80® Bus Mode Write Timing Example
Intel Bus Mode
Chip selects configured for Intel Bus Mode modify the eZ80 bus signals to duplicate a
four-state memory transfer similar to that found on Intel-style microprocessors. The bus
signals and ZLP12840 pins are mapped as illustrated in Figure 9. In Intel Bus Mode, the
user can select either multiplexed or non-multiplexed address and data buses. In non-multiplexed operation, the address and data buses are separate. In multiplexed operation, the
lower byte of the address, ADDR[7:0], also appears on the data bus, DATA[7:0], during
State T1 of the Intel Bus Mode cycle. During multiplexed operation, the lower byte of the
address bus also appears on the address bus in addition to the data bus.
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Bus Mode
Controller
eZ80 Bus Mode
Signals (Pins)
Intel Bus
Signal Equvalents
INSTRD
ALE
RD
RD
WR
WR
WAIT
READY
MREQ
MREQ
IORQ
IORQ
ADDR[23:0]
ADDR[23:0]
ADDR[7:0]
DATA[7:0]
Multiplexed
Bus
Controller
DATA[7:0]
Figure 9. Intel® Bus Mode Signal and Pin Mapping
Intel Bus Mode (Separate Address and Data Buses)
During Read operations with separate address and data buses, the Intel Bus Mode employs
4 states (T1, T2, T3, and T4) as described in Table 16.
Table 16. Intel® Bus Mode Read States (Separate Address and Data Buses)
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STATE T1
The Read cycle begins in State T1. The CPU drives the address onto the
address bus and the associated Chip Select signal is asserted. The CPU
drives the ALE signal High at the beginning of T1. During the middle of T1,
the CPU drives ALE Low to facilitate the latching of the address.
STATE T2
During State T2, the CPU asserts the RD signal. Depending on the
instruction, either the MREQ or IORQ signal is asserted.
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Table 16. Intel® Bus Mode Read States (Separate Address and Data Buses)
STATE T3
During State T3, no bus signals are altered. If the external ReadY (WAIT)
pin is driven Low at least one eZ80 system clock cycle prior to the
beginning of State T3, additional WAIT states (TWAIT) are asserted until the
ReadY pin is driven High.
STATE T4
The CPU latches the Read data at the beginning of State T4. The CPU
deasserts the RD signal and completes the Intel Bus Mode cycle.
During Write operations with separate address and data buses, the Intel Bus Mode
employs 4 states (T1, T2, T3, and T4) as described in Table 17.
Table 17. Intel® Bus Mode Write States (Separate Address and Data Buses)
STATE T1
The Write cycle begins in State T1. The CPU drives the address onto the
address bus, the associated Chip Select signal is asserted, and the data is
driven onto the data bus. The CPU drives the ALE signal High at the
beginning of T1. During the middle of T1, the CPU drives ALE Low to
facilitate the latching of the address.
STATE T2
During State T2, the CPU asserts the WR signal. Depending on the
instruction, either the MREQ or IORQ signal is asserted.
STATE T3
During State T3, no bus signals are altered. If the external ReadY (WAIT)
pin is driven Low at least one eZ80 system clock cycle prior to the
beginning of State T3, additional WAIT states (TWAIT) are asserted until the
ReadY pin is driven High.
STATE T4
The CPU deasserts the WR signal at the beginning of State T4. The CPU
holds the data and address buses through the end of T4. The bus cycle is
completed at the end of T4.
Intel Bus Mode timing is illustrated for a Read operation in Figure 10 and for a Write
operation in Figure 11. If the ReadY signal (external WAIT pin) is driven Low prior to the
beginning of State T3, additional WAIT states (TWAIT) are asserted until the ReadY signal
is driven High. The Intel Bus Mode states can be configured for 2 to 15 eZ80 system clock
cycles. In the figures, each Intel® Bus Mode state is 2 eZ80 system clock cycles in duration. Figure 10 and Figure 11 also illustrate the assertion of one WAIT state (TWAIT) by
the selected peripheral.
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T1
T2
T3
TWAIT
T4
System Clock
ADDR[23:0]
DATA[7:0]
CSx
ALE
RD
READY
WR
MREQ
or IORQ
Figure 10. Intel® Bus Mode Read Timing Example (Separate Address and Data Buses)
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T1
T2
T3
TWAIT
T4
em Clock
DR[23:0]
DATA[7:0]
CSx
ALE
WR
READY
RD
MREQ
or IORQ
Figure 11. Intel® Bus Mode Write Timing Example (Separate Address and Data Buses)
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Intel® Bus Mode (Multiplexed Address and Data Bus)
During Read operations with multiplexed address and data, the Intel® Bus Mode employs
4 states (T1, T2, T3, and T4) as described in Table 18.
Table 18. Intel® Bus Mode Read States (Multiplexed Address and Data Bus)
STATE T1
The Read cycle begins in State T1. The CPU drives the address onto the
DATA bus and the associated Chip Select signal is asserted. The CPU
drives the ALE signal High at the beginning of T1. During the middle of T1,
the CPU drives ALE Low to facilitate the latching of the address.
STATE T2
During State T2, the CPU removes the address from the DATA bus and
asserts the RD signal. Depending upon the instruction, either the MREQ or
IORQ signal is asserted.
STATE T3
During State T3, no bus signals are altered. If the external ReadY (WAIT)
pin is driven Low at least one eZ80 system clock cycle prior to the
beginning of State T3, additional WAIT states (TWAIT) are asserted until the
ReadY pin is driven High.
STATE T4
The CPU latches the Read data at the beginning of State T4. The CPU deasserts the RD signal and completes the Intel® Bus Mode cycle.
During Write operations with multiplexed address and data, the Intel® Bus Mode employs
4 states (T1, T2, T3, and T4) as described in Table 19.
Table 19. Intel® Bus Mode Write States (Multiplexed Address and Data Bus)
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STATE T1
The Write cycle begins in State T1. The CPU drives the address onto the
DATA bus and drives the ALE signal High at the beginning of T1. During
the middle of T1, the CPU drives ALE Low to facilitate the latching of the
address.
STATE T2
During State T2, the CPU removes the address from the DATA bus and
drives the Write data onto the DATA bus. The WR signal is asserted to
indicate a Write operation.
STATE T3
During State T3, no bus signals are altered. If the external ReadY (WAIT)
pin is driven Low at least one eZ80 system clock cycle prior to the
beginning of State T3, additional WAIT states (TWAIT) are asserted until the
ReadY pin is driven High.
STATE T4
The CPU deasserts the Write signal at the beginning of T4 identifying the
end of the Write operation. The CPU holds the data and address buses
through the end of T4. The bus cycle is completed at the end of T4.
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Signal timing for Intel® Bus Mode with multiplexed address and data is illustrated for a
Read operation in Figure 12 and for a Write operation in Figure 13. In the figures, each
Intel® Bus Mode state is 2 eZ80 system clock cycles in duration. Figure 12 and Figure 13
also illustrate the assertion of one WAIT state (TWAIT) by the selected peripheral.
T1
T2
T3
TWAIT
T4
System Clock
ADDR[23:0]
DATA[7:0]
CSx
ALE
RD
READY
WR
MREQ
or IORQ
Figure 12. Intel® Bus Mode Read Timing Example (Multiplexed Address and Data Bus)
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T1
T2
T3
TWAIT
T4
System Clock
ADDR[23:0]
DATA[7:0]
CSx
ALE
WR
READY
RD
MREQ
or IORQ
Figure 13. Intel® Bus Mode Write Timing Example (Multiplexed Address and Data Bus)
Motorola Bus Mode
Chip selects configured for Motorola Bus Mode modify the eZ80 bus signals to duplicate
an eight-state memory transfer similar to that found on Motorola-style microprocessors.
The bus signals (and ZLP12840 I/O pins) are mapped as illustrated in Figure 14.
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Bus Mode
Controller
eZ80 Bus Mode
Signals (Pins)
Motorola Bus
Signal Equvalents
INSTRD
AS
RD
DS
WR
R/W
WAIT
DTACK
MREQ
MREQ
IORQ
IORQ
ADDR[23:0]
ADDR[23:0]
DATA[7:0]
DATA[7:0]
Figure 14. Motorola Bus Mode Signal and Pin Mapping
During Write operations, the Motorola Bus Mode employs 8 states (S0, S1, S2, S3, S4, S5,
S6, and S7) as described in Table 20.
Table 20. Motorola Bus Mode Read States
STATE S0
The Read cycle starts in state S0. The CPU drives R/W High to identify a Read cycle.
STATE S1
Entering state S1, the CPU drives a valid address on the address bus, ADDR[23:0].
STATE S2
On the rising edge of state S2, the CPU asserts AS and DS.
STATE S3
During state S3, no bus signals are altered.
STATE S4
During state S4, the CPU waits for a cycle termination signal DTACK (WAIT), a peripheral
signal. If the termination signal is not asserted at least one full CPU clock period prior to the
rising clock edge at the end of S4, the CPU inserts WAIT (TWAIT) states until DTACK is
asserted. Each WAIT state is a full bus mode cycle.
STATE S5
During state S5, no bus signals are altered.
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Table 20. Motorola Bus Mode Read States (Continued)
STATE S6
During state S6, data from the external peripheral device is driven onto the data bus.
STATE S7
On the rising edge of the clock entering state S7, the CPU latches data from the addressed
peripheral device and deasserts AS and DS. The peripheral device deasserts DTACK at
this time.
The eight states for a Write operation in Motorola Bus Mode are described in Table 21.
Table 21. Motorola Bus Mode Write States
STATE S0
The Write cycle starts in S0. The CPU drives R/W High (if a preceding Write cycle leaves R/
W Low).
STATE S1
Entering S1, the CPU drives a valid address on the address bus.
STATE S2
On the rising edge of S2, the CPU asserts AS and drives R/W Low.
STATE S3
During S3, the data bus is driven out of the high-impedance state as the data to be written is
placed on the bus.
STATE S4
At the rising edge of S4, the CPU asserts DS. The CPU waits for a cycle termination signal
DTACK (WAIT). If the termination signal is not asserted at least one full CPU clock period
prior to the rising clock edge at the end of S4, the CPU inserts WAIT (TWAIT) states until
DTACK is asserted. Each WAIT state is a full bus mode cycle.
STATE S5
During S5, no bus signals are altered.
STATE S6
During S6, no bus signals are altered.
STATE S7
Upon entering S7, the CPU deasserts AS and DS. As the clock rises at the end of S7, the
CPU drives R/W High. The peripheral device deasserts DTACK at this time.
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S0
S1
S2
S3
S4
S5
S6
S7
System Clock
ADDR[23:0]
DATA[7:0]
CSx
AS
DS
R/W
DTACK
MREQ
or IORQ
Figure 15. Motorola Bus Mode Read Timing Example
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S0
S1
S2
S3
S4
S5
S6
S7
System Clock
ADDR[23:0]
DATA[7:0]
CSx
AS
DS
R/W
DTACK
MREQ
or IORQ
Figure 16. Motorola Bus Mode Write Timing Example
Switching Between Bus Modes
Each time the bus mode controller must switch from one bus mode to another, there is a
one-cycle eZ80 system clock delay. An extra clock cycle is not required for repeated
accesses in any of the bus modes; nor is it required when the ZLP12840 switches to eZ80
Bus Mode. The extra clock cycles are not shown in the timing examples. Due to the asynchronous nature of these bus protocols, the extra delay does not impact peripheral communication.
Chip Select Registers
Chip Select x Lower Bound Registers
For Memory Chip Selects, the Chip Select x Lower Bound register (see Table 22) defines
the lower bound of the address range for which the corresponding Memory Chip Select (if
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Product Specification
68
enabled) can be active. For I/O Chip Selects, this register defines the address to which
ADDR[15:8] is compared to generate an I/O Chip Select. All Chip Select lower bound
registers reset to 00h.
Table 22. Chip Select x Lower Bound Registers (CS0_LBR = 00A8h,
CS1_LBR = 00ABh, CS2_LBR = 00AEh, CS3_LBR = 00B1h)
Bit
7
6
5
4
3
2
1
0
CS0_LBR Reset
0
0
0
0
0
0
0
0
CS1_LBR Reset
0
0
0
0
0
0
0
0
CS2_LBR Reset
0
0
0
0
0
0
0
0
CS3_LBR Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
CSx_LBR
Value
Description
00h–FFh For Memory Chip Selects (CSx_IO = 0)
This byte specifies the lower bound of the Chip Select
address range. The upper byte of the address bus,
ADDR[23:16], is compared to the values contained in these
registers for determining whether a Memory Chip Select
signal must be generated.
For I/O Chip Selects (CSx_IO = 1)
This byte specifies the Chip Select address value.
ADDR[15:8] is compared to the values contained in these
registers for determining whether an I/O Chip Select signal
must be generated.
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Chip Select x Upper Bound Registers
For Memory Chip Selects, the Chip Select x Upper Bound registers, detailed in Table 23,
defines the upper bound of the address range for which the corresponding Chip Select (if
enabled) can be active. For I/O Chip Selects, this register produces no effect. The reset
state for the Chip Select 0 Upper Bound register is FFh, while the reset state for the other
Chip Select upper bound registers is 00h.
Table 23. Chip Select x Upper Bound Registers (CS0_UBR = 00A9h,
CS1_UBR = 00ACh, CS2_UBR = 00AFh, CS3_UBR = 00B2h)
Bit
7
6
5
4
3
2
1
0
CS0_UBR Reset
1
1
1
1
1
1
1
1
CS1_UBR Reset
0
0
0
0
0
0
0
0
CS2_UBR Reset
0
0
0
0
0
0
0
0
CS3_UBR Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
CSx_UBR
Value
00h–FFh
Description
For Memory Chip Selects (CSx_IO = 0)
This byte specifies the upper bound of the Chip Select
address range. The upper byte of the address bus,
ADDR[23:16], is compared to the values contained in
these registers for determining whether a Chip Select
signal should be generated.
For I/O Chip Selects (CSx_IO = 1)
No effect.
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Chip Select x Control Registers
The Chip Select x Control register, detailed in Table 24, enables the Chip Selects, specifies
the type of Chip Select, and sets the number of WAIT states. The reset state for the Chip
Select 0 Control register is E8h, while the reset state for the 3 other Chip Select control
registers is 00h.
Table 24. Chip Select x Control Registers (CS0_CTL = 00AAh, CS1_CTL =
00ADh, CS2_CTL = 00B0h, CS3_CTL = 00B3h)
Bit
7
6
5
4
3
2
1
0
CS0_CTL Reset
1
1
1
0
1
0
0
0
CS1_CTL Reset
0
0
0
0
0
0
0
0
CS2_CTL Reset
0
0
0
0
0
0
0
0
CS3_CTL Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R
R
R
CPU Access
Note: R/W = Read/Write; R = Read Only.
Bit
Position
[7:5]
CSx_WAIT*
Value
Description
000
0 WAIT states are asserted when this Chip Select is active.
001
1 WAIT state is asserted when this Chip Select is active.
010
2 WAIT states are asserted when this Chip Select is active.
011
3 WAIT states are asserted when this Chip Select is active.
100
4 WAIT states are asserted when this Chip Select is active.
101
5 WAIT states are asserted when this Chip Select is active.
110
6 WAIT states are asserted when this Chip Select is active.
111
7 WAIT states are asserted when this Chip Select is active.
4
CSx_IO
0
Chip Select is configured as a Memory Chip Select.
1
Chip Select is configured as an I/O Chip Select.
3
CSx_EN
0
Chip Select is disabled.
1
Chip Select is enabled.
[2:0]
000
Reserved.
Note: *These WAIT state settings apply only to the default eZ80 bus mode. See Table 25.
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Chip Select x Bus Mode Control Registers
The Chip Select Bus Mode register, detailed in Table 25, configures the Chip Select for
eZ80, Z80, Intel®, or Motorola Bus Modes. Changing the bus mode allows the ZLP12840
to interface to peripherals based on the Z80, Intel®-, or Motorola-style asynchronous bus
interfaces. When a bus mode other than eZ80 is programmed for a particular Chip Select,
the CSx_WAIT setting in that Chip Select Control Register is ignored.
Table 25. Chip Select x Bus Mode Control Registers (CS0_BMC = 00F0h,
CS1_BMC = 00F1h, CS2_BMC = 00F2h, CS3_BMC = 00F3h)
Bit
7
6
5
4
3
2
1
0
CS0_BMC Reset
0
0
0
0
0
0
1
0
CS1_BMC Reset
0
0
0
0
0
0
1
0
CS2_BMC Reset
0
0
0
0
0
0
1
0
CS3_BMC Reset
0
0
0
0
0
0
1
0
R/W
R/W
R/W
R
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write; R = Read Only.
Bit
Position
[7:6]
BUS_MODE
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Value
Description
00
eZ80 bus mode.
01
Z80 bus mode.
10
Intel® bus mode.
11
Motorola bus mode.
5
AD_MUX
0
Separate address and data.
1
Multiplexed address and data—appears on data bus
DATA[7:0].
4
0
Reserved.
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Product Specification
72
Bit
Position
[3:0]
BUS_CYCLE
Value
Description
0000
Not valid.
0001
Each bus mode state is 1 eZ80 clock cycle in duration.1, 2, 3
0010
Each bus mode state is 2 eZ80 clock cycles in duration.
0011
Each bus mode state is 3 eZ80 clock cycles in duration.
0100
Each bus mode state is 4 eZ80 clock cycles in duration.
0101
Each bus mode state is 5 eZ80 clock cycles in duration.
0110
Each bus mode state is 6 eZ80 clock cycles in duration.
0111
Each bus mode state is 7 eZ80 clock cycles in duration.
1000
Each bus mode state is 8 eZ80 clock cycles in duration.
1001
Each bus mode state is 9 eZ80 clock cycles in duration.
1010
Each bus mode state is 10 eZ80 clock cycles in duration.
1011
Each bus mode state is 11 eZ80 clock cycles in duration.
1100
Each bus mode state is 12 eZ80 clock cycles in duration.
1101
Each bus mode state is 13 eZ80 clock cycles in duration.
1110
Each bus mode state is 14 eZ80 clock cycles in duration.
1111
Each bus mode state is 15 eZ80 clock cycles in duration.
Notes:
1. Setting the BUS_CYCLE to 1 in Intel Bus Mode causes the ALE pin to not function properly.
2. Use of the external WAIT input pin in Z80 Mode requires that BUS_CYCLE is set to a value
greater than 1.
3. These BUS_CYCLE values are not valid in eZ80 bus mode. See Table 24.
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Watchdog Timer
The Watchdog Timer (WDT) helps protect against corrupt or unreliable software, power
faults, and other system-level problems which may place the eZ80 CPU into unsuitable
operating states. The ZLP12840 MCU WDT features:
•
•
Four programmable time-out periods: 218, 222, 225, and 227 clock cycles
•
A selectable time-out response: a time-out can be configured to generate either a
RESET or a non-maskable interrupt (NMI)
•
A WDT time-out RESET indicator flag
Two selectable WDT clock sources: the system clock or the real time clock source
(on-chip 32 kHz crystal oscillator or 50/60 Hz signal)
Figure 17 illustrates the block diagram for the Watchdog Timer.
Data[7:0]
Control Register/
Reset Register
WDT_CLK
RTC Clock
28-Bit
Upcounter
WDT Control Logic
System Clock
Time-Out Compare Logic
{WDT_PERIOD}
RESET
NMI to eZ80 CPU
Figure 17. Watchdog Timer Block Diagram
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Product Specification
74
Watchdog Timer Operation
Enabling and Disabling the WDT
The Watchdog Timer is disabled upon a system reset (RESET). To enable the WDT, the
application program must set the WDT_EN bit (bit 7) of the WDT_CTL register. When
enabled, the WDT cannot be disabled without a RESET.
Time-Out Period Selection
There are four choices of time-out periods for the WDT—218, 222, 225, and 227 system
clock cycles. The WDT time-out period is defined by the WDT_PERIOD field of the
WDT_CTL register (WDT_CTL[1:0]). The approximate time-out periods for two
different WDT clock sources is listed in Table 26.
Table 26. Watchdog Timer Approximate Time-Out Delays
Clock Source
Divider Value
Time Out Delay
32.768 kHz Crystal Oscillator
18
2
8.00 s
32.768 kHz Crystal Oscillator
222
128 s
32.768 kHz Crystal Oscillator
25
2
1024 s
32.768 kHz Crystal Oscillator
227
4096 s
18
20 MHz System Clock
2
20 MHz System Clock
222
20 MHz System Clock
2
25
1.68 s
20 MHz System Clock
227
6.71 s
50 MHz System Clock
2
18
50 MHz System Clock
222
50 MHz System Clock
2
25
0.67 s
50 MHz System Clock
227
2.68 s
13.1 ms
209.7 ms
5.2 ms*
83.9 ms*
RESET Or NMI Generation
Upon a WDT time-out, the RST_FLAG in the WDT_CTL register is set to 1. In addition,
the WDT can cause a RESET or send a nonmaskable interrupt (NMI) signal to the CPU.
The default operation is for the WDT to cause a RESET. It asserts/deasserts on the rising
edge of the clock. The RST_FLAG bit can be polled by the CPU to determine the source
of the RESET event.
If the NMI_OUT bit in the WDT_CTL register is set to 1, then upon time-out, the WDT
asserts an NMI for CPU processing. The RST_FLAG bit can be polled by the CPU to
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75
determine the source of the NMI event, provided that the last RESET was not caused by
the WDT.
Watchdog Timer Registers
Watchdog Timer Control Register
The Watchdog Timer Control register, described in Table 27, is an 8-bit Read/Write register used to enable the Watchdog Timer, set the time-out period, indicate the source of the
most recent RESET, and select the required operation upon WDT time-out.
Table 27. Watchdog Timer Control Register (WDT_CTL = 0093h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0/1
0
0
0
0
0
R/W
R/W
R
R/W
R/W
R
R/W
R/W
CPU Access
Note: R = Read only; R/W = Read/Write.
Bit
Position
Value
Description
7
WDT_EN
0
WDT is disabled.
1
WDT is enabled. When enabled, the WDT cannot be
disabled without a full RESET.
6
NMI_OUT
0
WDT time-out resets the CPU.
1
WDT time-out generates a nonmaskable interrupt (NMI) to
the CPU.
5
RST_FLAG*
0
RESET caused by external full-chip reset or ZDI reset.
1
RESET caused by WDT time-out. This flag is set by the WDT
time-out, even if the NMI_OUT flag is set to 1. The CPU can
poll this bit to determine the source of the RESET or NMI.
[4:3]
WDT_CLK
00
WDT clock source is system clock.
01
WDT clock source is Real-Time Clock source (32 kHz
on-chip oscillator or 50/60Hz input as set by RTC_CTRL[4]) .
10
Reserved.
11
Reserved.
0
Reserved.
2
RESERVED
Note: *RST_FLAG is only cleared by a non-WDT RESET.
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76
Bit
Position
[1:0]
WDT_PERIOD
Value
Description
00
WDT time-out period is 227 clock cycles.
01
WDT time-out period is 225 clock cycles.
10
WDT time-out period is 222 clock cycles.
11
WDT time-out period is 218 clock cycles.
Note: *RST_FLAG is only cleared by a non-WDT RESET.
Watchdog Timer Reset Register
The Watchdog Timer Reset register, described in Table 28, is an 8-bit Write-Only register.
The Watchdog Timer is reset when an A5h value followed by 5Ah is written to this
register. Any amount of time can occur between the writing of the A5h value and the 5Ah
value, so long as the WDT time-out does not occur prior to completion.
Table 28. Watchdog Timer Reset Register (WDT_RR = 0094h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: X = Undefined; W = Write only.
Bit
Position
[7:0]
WDT_RR
PS013015-0316
Value
Description
A5h
The first Write value required to reset the WDT prior to a
time-out.
5Ah
The second Write value required to reset the WDT prior to a
time-out. If an A5h, 5Ah sequence is written to WDT_RR, the
WDT timer is reset to its initial count value, and counting
resumes.
Watchdog Timer
eZ80L92 MCU
Product Specification
77
Programmable Reload Timers
The ZLP12840 MCU features six Programmable Reload Timers (PRT). Each PRT contains a 16-bit downcounter and a 16-bit reload register. In addition, each PRT features a
clock prescaler with four selectable taps for CLK ÷ 4, CLK ÷ 16, CLK ÷ 64, and
CLK ÷ 256. Each timer can be individually enabled to operate in either SINGLE PASS or
CONTINUOUS mode. The timer can be programmed to start, stop, restart from the
current value, or restart from the initial value, and generate interrupts to the CPU.
Four of the Programmable Reload Timers (timers 0–3) feature a selectable clock source
input. The input for these timers can be either the system clock or the Real-Time Clock
(RTC) source. Timers 0–3 can also be used for event counting, with their inputs received
from a GPIO port pin. Output from timers 4 and 5 can be directed to a GPIO port pin.
Each of the six PRTs available on the ZLP12840 can be controlled individually. They do
not share the same counters, reload registers, control registers, or interrupt signals.
A simplified block diagram of a programmable reload timer is illustrated in Figure 18.
Data[7:0]
Data[7:0]
Reload Registers
{TMRx_RR_H, TMRx_RR_L}
Control Register
TMRx_CTL
16-Bit
Down Counter
PRT
Control Logic
System Clock
Adjustable
Clock
Prescaler
RTC Source
GPIO Pin
2
IRQ to eZ80 CPU
Timer Out
2
TMRx_IN TMRx_CTL[3:2]
(Timers 0—3
only)
Data Registers
{TMRx_DR_H, TMRx_DR_L}
TOUT_EN
(Timers 4—5 only)
Data[7:0]
Figure 18. Programmable Reload Timer Block Diagram
Programmable Reload Timer Operation
Setting Timer Duration
There are three factors to consider when determining Programmable Reload Timer
duration—clock frequency, clock divider ratio, and initial count value. Minimum duration
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Product Specification
78
of the timer is achieved by loading 0001h. Maximum duration is achieved by loading
0000h, because the timer first rolls over to FFFFh and then continues counting down to
0000h.
The time-out period of the PRT is returned by the following equation:
PRT Time-Out Period
=
Clock Divider Ratio x Reload Value
System Clock Frequency
To calculate the time-out period with the above equation when using an initial value of
0000h, enter a reload value of 65536 (FFFFh + 1).
Minimum time-out duration is 4 times longer than the input clock period and is generated
by setting the clock divider ratio to 1:4 and the reload value to 0001h. Maximum time-out
duration is 224 (16,777,216) times longer than the input clock period and is generated by
setting the clock divider ratio to 1:256 and the reload value to 0000h.
SINGLE PASS Mode
In SINGLE PASS mode, when the end-of-count value, 0000h, is reached, counting halts,
the timer is disabled, and the PRT_EN bit resets to 0. To restart the timer, the CPU must
reenable the timer by setting the PRT_EN bit to 1. An example of a PRT operating in
SINGLE PASS mode is illustrated in Figure 19. Timer register information is indicated
in Table 29.
CLK
CLKEN
IOWRN
tCNTH7:0]
t CNTL7:0]
0
0
4
3
2
1
0
IRQ
Figure 19. PRT SINGLE PASS Mode Operation Example
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Table 29. PRT SINGLE PASS Mode Operation Example
Parameter
Control Register(s)
Value
PRT Enabled
TMRx_CTL[0]
1
Reload and Restart Enabled
TMRx_CTL[1]
1
PRT Clock Divider = 4
TMRx_CTL[3:2]
SINGLE PASS Mode
TMRx_CTL[4]
0
PRT Interrupt Enabled
TMRx_CTL[6]
1
PRT Reload Value
{TMRx_RR_H, TMRx_RR_L}
00b
0004h
CONTINUOUS Mode
In CONTINUOUS mode, when the end-of-count value, 0000h, is reached, the timer
automatically reloads the 16-bit start value from the Timer Reload registers,
TMRx_RR_H and TMRx_RR_L. Downcounting continues on the next clock edge. In
CONTINUOUS mode, the PRT continues to count until disabled. An example of a PRT
operating in CONTINUOUS mode is illustrated in Figure 20. Timer register information
is indicated in Table 30.
CLK
CLKEN
IOWRN
tCNTH7:0]
t CNTL7:0]
0
0
4
3
2
1
4
IRQ
Figure 20. PRT CONTINUOUS Mode Operation Example
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Table 30. PRT CONTINUOUS Mode Operation Example
Parameter
Control Register(s)
Value
PRT Enabled
TMRx_CTL[0]
1
Reload and Restart Enabled
TMRx_CTL[1]
1
PRT Clock Divider = 4
TMRx_CTL[3:2]
CONTINUOUS Mode
TMRx_CTL[4]
1
PRT Interrupt Enabled
TMRx_CTL[6]
1
PRT Reload Value
{TMRx_RR_H, TMRx_RR_L}
00b
0004h
Reading the Current Count Value
The CPU is capable of reading the current count value while the timer is running. This
Read event does not affect timer operation. The High byte of the current count value is
latched during a Read of the Low byte.
Timer Interrupts
The timer interrupt flag, PRT_IRQ, is set to 1 whenever the timer reaches its end-of-count
value, 0000h, in SINGLE PASS mode, or when the timer reloads the start value in
CONTINUOUS mode. The interrupt flag is only set when the timer reaches 0000h (or
reloads) from 0001h. The timer interrupt flag is not set to 1 when the timer is loaded with
the value 0000h, which selects the maximum time-out period.
The CPU can be programmed to poll the PRT_IRQ bit for the time-out event. Alternatively, an interrupt service request signal can be sent to the CPU by setting IRQ_EN to 1.
Then, when the end-of-count value, 0000h, is reached and PRT_IRQ is set to 1, an
interrupt service request signal is passed to the CPU. PRT_IRQ is cleared to 0 and the
interrupt service request signal is inactivated whenever the CPU reads from the timer control registers, TMRx_CTL.
Timer Input Source Selection
Timers 0–3 feature programmable input source selection. By default, the input is taken
from the ZLP12840’s system clock. Alternatively, Timers 0–3 can take their input from
port input pins PB0 (Timers 0 and 2) or PB1 (Timers 1 and 3). Timers 0–3 can also use the
Real-Time Clock clock source (50, 60, or 32768 Hz) as their clock sources. When the
timer clock source is the Real-Time Clock signal, the timer decrements on the second
rising edge of the system clock following the falling edge of the RTC_XOUT pin. The
input source for these timers is set using the Timer Input Source Select register.
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Programmable Reload Timers
eZ80L92 MCU
Product Specification
81
Event Counter
When Timers 0–3 are configured to take their inputs from port input pins PB0 and PB1,
they function as event counters. For event counting, the clock prescaler is bypassed.
The PRT counters decrement on every rising edge of the port pin. The port pins must
be configured as inputs. Due to the input sampling on the pins, the event input signal frequency is limited to one-half the system clock frequency. Input sampling on the port pins
results in the PRT counter being updated on the fifth rising edge of the system clock after
the rising edge occurs at the port pin.
Timer Output
Two of the Programmable Reload Timers (Timers 4 and 5) can be directed to GPIO Port B
output pins (PB4 and PB5, respectively). To enable the Timer Out feature, the GPIO port
pin must be configured for alternate functions. After reset, the Timer Output feature is
disabled by default. The GPIO output pin toggles each time the PRT reaches its end-ofcount value. In CONTINUOUS mode operation, the disabling of the Timer Output feature
results in a Timer Output signal period that is twice the PRT time-out period. Examples of
the Timer Output operation are illustrated in Figure 21 and Table 31. In these examples,
the GPIO output is assumed to be Low (0) when the Timer Output function is enabled.
CLK
PRT Clock
(Clock 4)
IOWRN
I/O Write to TMRx_CTL Enables PRT
PRT Count
Value
X
3
2
1
2
3
1
Timer
Output
Figure 21. PRT Timer Output Operation Example
Table 31. PRT Timer Out Operation Example
PS013015-0316
Parameter
Control Register(s)
Value
PRT Enabled
TMRx_CTL[0]
1
Reload and Restart Enabled
TMRx_CTL[1]
1
Programmable Reload Timers
eZ80L92 MCU
Product Specification
82
Table 31. PRT Timer Out Operation Example (Continued)
Parameter
Control Register(s)
Value
PRT Clock Divider = 4
TMRx_CTL[3:2]
CONTINUOUS Mode
TMRx_CTL[4]
1
PRT Reload Value
{TMRx_RR_H,
TMRx_RR_L}
0003h
00b
Programmable Reload Timer Registers
Each programmable reload timer is controlled using five 8-bit registers. These registers
are the Timer Control register, Timer Reload Low Byte register, Timer Reload High Byte
register, Timer Data Low Byte register, and Timer Data High Byte register.
The Timer Control register can be read or written to. The timer reload registers are WriteOnly and are located at the same I/O address as the timer data registers, which are ReadOnly.
Timer Control Registers
The Timer Control register, described in Table 32, is used to control operation of the timer,
including enabling the timer, selecting the clock divider, enabling the interrupt, selecting
between CONTINUOUS and SINGLE PASS modes, and enabling the auto-reload feature.
Table 32. Timer Control Registers (TMR0_CTL = 0080h, TMR1_CTL = 0083h,
TMR2_CTL = 0086h, TMR3_CTL = 0089h, TMR4_CTL = 008Ch, or TMR5_CTL
= 008Fh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Note: R = Read only; R/W = Read/Write.
Bit
Position
7
PRT_IRQ
PS013015-0316
Value
Description
0
The timer does not reach its end-of-count value. This bit is reset
to 0 every time the TMRx_CTL register is read.
1
The timer reaches its end-of-count value. If IRQ_EN is set to 1,
an interrupt signal is sent to the CPU. This bit remains 1 until the
TMRx_CTL register is read.
Programmable Reload Timers
eZ80L92 MCU
Product Specification
83
6
IRQ_EN
0
Timer interrupt requests are disabled.
1
Timer interrupt requests are enabled.
5
0
Reserved.
4
PRT_MODE
0
The timer operates in SINGLE PASS mode. PRT_EN (bit 0) is
reset to 0, and counting stops when the end-of-count value is
reached.
1
The timer operates in CONTINUOUS mode. The timer reload
value is written to the counter when the end-of-count value is
reached.
00
Clock ÷ 4 is the timer input source.
01
Clock ÷ 16 is the timer input source.
10
Clock ÷ 64 is the timer input source.
11
Clock ÷ 256 is the timer input source.
1
RST_EN
0
The reload and restart function is disabled.
1
The reload and restart function is enabled. When a 1 is written to
RST_EN, the values in the reload registers are loaded into the
downcounter and the timer restarts.
0
PRT_EN
0
The programmable reload timer is disabled.
1
The programmable reload timer is enabled.
[3:2]
CLK_DIV
Timer Data Registers—Low Byte
This Read-Only register returns the Low byte of the current count value of the selected
timer. The Timer Data Register—Low Byte, detailed in Table 33, can be read while the
timer is in operation. Reading the current count value does not affect timer operation. To
read the 16-bit data of the current count value, {TMRx_DR_H[7:0], TMRx_DR_L[7:0]},
first read the Timer Data Register—Low Byte and then read the Timer Data Register—High Byte. The Timer Data Register—High Byte value is latched when a Read of the
Timer Data Register—Low Byte occurs.
Note: The Timer Data registers and Timer Reload registers share the same address space.
PS013015-0316
Programmable Reload Timers
eZ80L92 MCU
Product Specification
84
Table 33. Timer Data Registers—Low Byte (TMR0_DR_L = 0081h,
TMR1_DR_L = 0084h, TMR2_DR_L = 0087h, TMR3_DR_L = 008Ah,
TMR4_DR_L = 008Dh, or TMR5_DR_L = 0090h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
Bit
Position
[7:0]
TMRx_DR_L
Value
Description
00h–FFh These bits represent the Low byte of the 2-byte timer data
value, {TMRx_DR_H[7:0], TMRx_DR_L[7:0]}. Bit 7 is bit 7
of the 16-bit timer data value. Bit 0 is bit 0 (lsb) of the 16-bit
timer data value.
Timer Data Registers—High Byte
This Read-Only register returns the High byte of the current count value of the selected
timer. The Timer Data Register—High Byte, detailed in Table 34, can be read while the
timer is in operation. Reading the current count value does not affect timer operation. To
read the 16-bit data of the current count value, {TMRx_DR_H[7:0], TMRx_DR_L[7:0]},
first read the Timer Data Register—Low Byte and then read the Timer Data Register—High Byte. The Timer Data Register—High Byte value is latched when a Read of the
Timer Data Register—Low Byte occurs.
Note: The timer data registers and timer reload registers share the same address space.
Table 34. Timer Data Registers—High Byte (TMR0_DR_H = 0082h,
TMR1_DR_H = 0085h, TMR2_DR_H = 0088h, TMR3_DR_H = 008Bh,
TMR4_DR_H = 008Eh, or TMR5_DR_H = 0091h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
PS013015-0316
Programmable Reload Timers
eZ80L92 MCU
Product Specification
85
Bit
Position
Value
Description
[7:0]
00h–FFh These bits represent the High byte of the 2-byte timer data
TMRx_DR_H
value, {TMRx_DR_H[7:0], TMRx_DR_L[7:0]}. Bit 7 is bit 15
(msb) of the 16-bit timer data value. Bit 0 is bit 8 of the 16-bit
timer data value.
Timer Reload Registers—Low Byte
The Timer Reload Register—Low Byte, described in Table 35, stores the least significant
byte (LSB) of the 2-byte timer reload value. In CONTINUOUS mode, the timer reload
value is reloaded into the timer upon end-of-count. When RST_EN (TMRx_CTL[1]) is set
to 1 to enable the automatic reload and restart function, the timer reload value is written to
the timer on the next rising edge of the clock.
Note: The Timer Data registers and Timer Reload registers share the same address space.
Table 35. Timer Reload Registers—Low Byte (TMR0_RR_L = 0081h,
TMR1_RR_L = 0084h, TMR2_RR_L = 0087h, TMR3_RR_L = 008Ah,
TMR4_RR_L = 008Dh, or TMR5_RR_L = 0090h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write only.
Bit
Position
[7:0]
TMRx_RR_L
PS013015-0316
Value
Description
00h–FFh These bits represent the Low byte of the 2-byte timer
reload value, {TMRx_RR_H[7:0], TMRx_RR_L[7:0]}. Bit 7
is bit 7 of the 16-bit timer reload value. Bit 0 is bit 0 (lsb) of
the 16-bit timer reload value.
Programmable Reload Timers
eZ80L92 MCU
Product Specification
86
Timer Reload Registers—High Byte
The Timer Reload Register—High Byte, detailed in Table 36, stores the most significant
byte (MSB) of the 2-byte timer reload value. In CONTINUOUS mode, the timer reload
value is reloaded into the timer upon end-of-count. When RST_EN (TMRx_CTL[1]) is set
to 1 to enable the automatic reload and restart function, the timer reload value is written to
the timer on the next rising edge of the clock.
Note: The Timer Data registers and Timer Reload registers share the same address space.
Table 36. Timer Reload Registers—High Byte (TMR0_RR_H = 0082h,
TMR1_RR_H = 0085h, TMR2_RR_H = 0088h, TMR3_RR_H = 008Bh,
TMR4_RR_H = 008Eh, or TMR5_RR_H = 0091h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write only.
Bit
Position
[7:0]
TMRx_RR_H
Value
Description
00h–FFh These bits represent the High byte of the 2-byte timer
reload value, {TMRx_RR_H[7:0], TMRx_RR_L[7:0]}. Bit 7
is bit 15 (msb) of the 16-bit timer reload value. Bit 0 is bit 8
of the 16-bit timer reload value.
Timer Input Source Select Register
The Timer Input Source Select register, detailed in Table 37, sets the input source for Programmable Reload Timer 0–3 (TMR0, TMR1, TMR2, TMR3). Event frequency must be
less than one-half of the system clock frequency. When configured for event inputs
through the port pins, the Timers decrement on the fifth system clock rising edge following the rising edge of the port pin.
PS013015-0316
Programmable Reload Timers
eZ80L92 MCU
Product Specification
87
Table 37. Timer Input Source Select Register (TMR_ISS = 0092h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:6]
TMR3_IN
[5:4]
TMR2_IN
[3:2]
TMR1_IN
[1:0]
TMR0_IN
PS013015-0316
Value
Description
00
The timer counts at the system clock divided by the
prescaler.
01
The timer event input is the Real-Time Clock source
(32 kHz or 50/60 Hz—refer to the Real Time Clock section
on page 88 for details).
10
The timer event input is the GPIO Port B pin 1.
11
The timer event input is the GPIO Port B pin 1.
00
The timer counts at the system clock divided by the
prescaler.
01
The timer event input is the Real-Time Clock source
(32 kHz or 50/60 Hz—refer to the Real Time Clock section
on page 88 for details).
10
The timer event input is the GPIO Port B pin 0.
11
The timer event input is the GPIO Port B pin 0.
00
The timer counts at the system clock divided by the
prescaler.
01
The timer event input is the Real-Time Clock source
(32 kHz or 50/60 Hz—refer to the Real Time Clock section
on page 88 for details).
10
The timer event input is the GPIO Port B pin 1.
11
The timer event input is the GPIO Port B pin 1.
00
Timer counts at system clock divided by prescaler.
01
Timer event input is Real-Time Clock source
(32 kHz or 50/60 Hz—refer to the Real Time Clock section
on page 88 for details).
10
The timer event input is the GPIO Port B pin 0.
11
The timer event input is the GPIO Port B pin 0.
Programmable Reload Timers
eZ80L92 MCU
Product Specification
88
Real Time Clock
The real time clock (RTC) keeps time by maintaining a count of seconds, minutes, hours,
day-of-the-week, day-of-the-month, year, and century. The current time is kept in 24-hour
format. The format for all count and alarm registers is selectable between binary and
binary-coded-decimal (BCD) operations. The calendar operation maintains the correct day
of the month and automatically compensates for leap year only when binary-coded-decimal operation is enabled. A simplified block diagram of the RTC and the associated onchip, low-power, 32 kHz oscillator is illustrated in Figure 22. Connections to an external
battery supply and 32 kHz crystal network are also demonstrated in Figure 22.
RTC_VDD
Battery
VDD
to eZ80 CPU
IRQ
Real-Time Clock
ADDR[15:0]
DATA[7:0]
R1
RTC_XOUT
RTC Clock
C
System Clock
Low-Power
32 KHz Oscillator
VDD
32 KHz
Crystal
Enable
CLK_SEL
(RTC_CTRL[4])
RTC_XIN
C
Figure 22. Real Time Clock and 32 kHz Oscillator Block Diagram
PS013015-0316
Real Time Clock
eZ80L92 MCU
Product Specification
89
Real Time Clock Alarm
The clock can be programmed to generate an alarm condition when the current count
matches the alarm set-point registers. Alarm registers are available for seconds, minutes,
hours, and day-of-the-week. Each alarm can be independently enabled. To generate an
alarm condition, the current time must match all enabled alarm values. For example, if the
day-of-the-week and hour alarms are both enabled, the alarm only occurs at the specified
hour on the specified day. The alarm triggers an interrupt if the interrupt enable bit,
INT_EN, is set. The alarm flag, ALARM, and corresponding interrupt to the CPU are
cleared by reading the RTC_CTRL register.
Alarm value registers and alarm control registers can be written at any time. Alarm conditions are generated when the count value matches the alarm value. The comparison of
alarm and count values occurs whenever the RTC count increments (one time every second). The RTC can also be forced to perform a comparison at any time by writing a 0 to
RTC_UNLOCK (RTC_UNLOCK is not required to be changed to a 1 first).
Real Time Clock Oscillator and Source Selection
The RTC count is driven by either an external 32 kHz on-chip oscillator or a 50/60 Hz
power-line frequency input connected to the 32 kHz RTC_XOUT pin. An internal divider
compensates for each of these options. The clock source and power-line frequencies are
selected in the RTC_CTRL register. Writing to the RTC_CTRL register resets the clock
divider.
Real Time Clock Battery Backup
The power supply pin (RTC_VDD) for the RTC and associated low-power 32 kHz
oscillator is isolated from the other power supply pins on the ZLP12840 MCU. To ensure
that the RTC continues to keep time in the event of loss of line power to the application,
a battery can be used to supply power to the RTC and the oscillator via the RTC_VDD pin.
All VSS (ground) pins must be connected together on the printed circuit assembly.
Real Time Clock Recommended Operation
Following a RESET from a powered-down condition, the counter values of the RTC are
undefined and all alarms are disabled. After a RESET from a powered-down condition,
the following procedure is recommended:
•
•
•
•
PS013015-0316
Write to RTC_CTRL to set RTC_UNLOCK and CLK_SEL.
Write values to the RTC count registers to set the current time.
Write values to the RTC alarm registers to set the appropriate alarm conditions.
Write to RTC_CTRL to clear RTC_UNLOCK; clearing the RTC_UNLOCK bit resets
and enables the clock divider.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
90
Real Time Clock Registers
The real time clock registers are accessed via the address and data bus using I/O
instructions. RTC_UNLOCK controls access to the RTC count registers. When unlocked
(RTC_UNLOCK = 1), the RTC count is disabled and the count registers are Read/Write.
When locked (RTC_UNLOCK = 0), the RTC count is enabled and the count registers are
Read-Only. The default, at RESET, is for the RTC to be locked.
Real Time Clock Seconds Register
This register contains the current seconds count. The value in the RTC_SEC register is
unchanged by a RESET. The current setting of BCD_EN determines whether the values in
this register are binary (BCD_EN = 0) or binary-coded decimal (BCD_EN = 1). Access to
this register is Read-Only if the RTC is locked and Read/Write if the RTC is unlocked.
See Table 38.
Table 38. Real Time Clock Seconds Register (RTC_SEC = 00E0h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TEN_SEC
0–5
The tens digit of the current seconds count.
[3:0]
SEC
0–9
The ones digit of the current seconds count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
SEC
PS013015-0316
Value
Description
00h–3Bh The current seconds count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
91
Real Time Clock Minutes Register
This register contains the current minutes count. See Table 39.
Table 39. Real Time Clock Minutes Register (RTC_MIN = 00E1h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TEN_MIN
0–5
The tens digit of the current minutes count.
[3:0]
MIN
0–9
The ones digit of the current minutes count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
MIN
PS013015-0316
Value
Description
00h–3Bh
The current minutes count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
92
Real Time Clock Hours Register
This register contains the current hours count. See Table 40.
Table 40. Real Time Clock Hours Register (RTC_HRS = 00E2h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TEN_HRS
0–2
The tens digit of the current hours count.
[3:0]
HRS
0–9
The ones digit of the current hours count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
HRS
PS013015-0316
Value
Description
00h–17h
The current hours count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
93
Real Time Clock Day-of-the-Week Register
This register contains the current day-of-the-week count. The RTC_DOW register begins
counting at 01h. See Table 41.
Table 41. Real Time Clock Day-of-the-Week Register (RTC_DOW = 00E3h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
X
X
X
X
CPU Access
R
R
R
R
R/W*
R/W*
R/W*
R/W*
Note: X = Unchanged by RESET; R = Read Only; R/W* = Read-only if RTC locked, Read/Write if
RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value
Description
[7:4]
0000
Reserved.
[3:0]
DOW
1-7
The current day-of-the-week.count.
Binary Operation (BCD_EN = 0)
PS013015-0316
Bit
Position
Value
Description
[7:4]
0000
Reserved.
[3:0]
DOW
01h–07h
The current day-of-the-week count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
94
Real Time Clock Day-of-the-Month Register
This register contains the current day-of-the-month count. The RTC_DOM register begins
counting at 01h. See Table 42.
Table 42. Real Time Clock Day-of-the-Month Register (RTC_DOM = 00E4h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TENS_DOM
0–3
The tens digit of the current day-of-the-month count.
[3:0]
DOM
0–9
The ones digit of the current day-of-the-month count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
DOM
PS013015-0316
Value
Description
01h–1Fh
The current day-of-the-month count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
95
Real Time Clock Month Register
This register contains the current month count. See Table 43.
Table 43. Real Time Clock Month Register (RTC_MON = 00E5h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TENS_MON
0–1
The tens digit of the current month count.
[3:0]
MON
0–9
The ones digit of the current month count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
MON
PS013015-0316
Value
Description
01h–0Ch The current month count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
96
Real Time Clock Year Register
This register contains the current year count. See Table 44.
Table 44. Real Time Clock Year Register (RTC_YR = 00E6h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TENS_YR
0–9
The tens digit of the current year count.
[3:0]
YR
0–9
The ones digit of the current year count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
YR
PS013015-0316
Value
Description
00h–63h
The current year count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
97
Real Time Clock Century Register
This register contains the current century count. See Table 45.
Table 45. Real Time Clock Century Register (RTC_CEN = 00E7h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
R/W*
CPU Access
Note: X = Unchanged by RESET; R/W* = Read-only if RTC locked, Read/Write if RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
TENS_CEN
0–9
The tens digit of the current century count.
[3:0]
CEN
0–9
The ones digit of the current century count.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
CEN
PS013015-0316
Value
Description
00h–63h
The current century count.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
98
Real Time Clock Alarm Seconds Register
This register contains the alarm seconds value. See Table 46.
Table 46. Real Time Clock Alarm Seconds Register (RTC_ASEC = 00E8h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: X = Unchanged by RESET; R/W = Read/Write.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
ATEN_SEC
0–5
The tens digit of the alarm seconds value.
[3:0]
ASEC
0–9
The ones digit of the alarm seconds value.
Binary Operation (BCD_EN = 0)
PS013015-0316
Bit
Position
Value Description
[7:0]
ASEC
00h–3 The alarm seconds value.
Bh
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
99
Real Time Clock Alarm Minutes Register
This register contains the alarm minutes value. See Table 47.
Table 47. Real Time Clock Alarm Minutes Register (RTC_AMIN = 00E9h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: X = Unchanged by RESET; R/W = Read/Write.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
ATEN_MIN
0–5
The tens digit of the alarm minutes value.
[3:0]
AMIN
0–9
The ones digit of the alarm minutes value.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
AMIN
PS013015-0316
Value
Description
00h–3Bh
The alarm minutes value.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
100
Real Time Clock Alarm Hours Register
This register contains the alarm hours value. See Table 48.
Table 48. Real Time Clock Alarm Hours Register (RTC_AHRS = 00EAh)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: X = Unchanged by RESET; R/W = Read/Write.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
ATEN_HRS
0–2
The tens digit of the alarm hours value.
[3:0]
AHRS
0–9
The ones digit of the alarm hours value.
Binary Operation (BCD_EN = 0)
Bit
Position
[7:0]
AHRS
PS013015-0316
Value
Description
00h–17h
The alarm hours value.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
101
Real Time Clock Alarm Day-of-the-Week Register
This register contains the alarm day-of-the-week value. See Table 49.
Table 49. Real Time Clock Alarm Day-of-the-Week Register (RTC_ADOW =
00EBh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
X
X
X
X
CPU Access
R
R
R
R
R/W*
R/W*
R/W*
R/W*
Note: X = Unchanged by RESET; R = Read Only; R/W* = Read-only if RTC locked, Read/Write if
RTC unlocked.
Binary-Coded-Decimal Operation (BCD_EN = 1)
Bit
Position
Value Description
[7:4]
0000
Reserved.
[3:0]
ADOW
1-7
The alarm day-of-the-week.value.
Binary Operation (BCD_EN = 0)
PS013015-0316
Bit
Position
Value
Description
[7:4]
0000
Reserved.
[3:0]
ADOW
01h–07h
The alarm day-of-the-week value.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
102
Real Time Clock Alarm Control Register
This register contains alarm enable bits for the real-time clock. The RTC_ACTRL register
is cleared by a RESET. See Table 50.
Table 50. Real Time Clock Alarm Control Register (RTC_ACTRL = 00ECh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R/W
R/W
R/W
R/W
Note: X = Unchanged by RESET; R = Read-only; R/W = Read/Write.
Bit
Position
Value
Description
[7:4]
0000
Reserved.
3
ADOW_EN
0
The day-of-the-week alarm is disabled.
1
The day-of-the-week alarm is enabled.
2
AHRS_EN
0
The hours alarm is disabled.
1
The hours alarm is enabled.
1
AMIN_EN
0
The minutes alarm is disabled.
1
The minutes alarm is enabled.
0
ASEC_EN
0
The seconds alarm is disabled.
1
The seconds alarm is enabled.
Real-Time Clock Control Register
This register contains control and status bits for the real-time clock. Some bits in the
RTC_CTRL register are cleared by a RESET. The ALARM flag and associated interrupt
(if INT_EN is enabled) are cleared by reading this register. The ALARM flag is updated
by clearing (locking) RTC_UNLOCK or by an increment of the RTC count. Writing to the
RTC_CTRL register also resets the RTC count prescaler allowing the RTC to be synchronized to another time source.
SLP_WAKE indicates if an RTC alarm condition initiated the CPU recovery from SLEEP
mode. This bit can be checked after RESET to determine if a sleep-mode recovery is
caused by the RTC. SLP_WAKE is cleared by a Read of the RTC_CTRL register.
Setting BCD_EN causes the RTC to use BCD counting in all registers including the alarm
set points.
PS013015-0316
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
103
CLK_SEL and FREQ_SEL select the RTC clock source. If the 32 kHz crystal option is
selected the oscillator is enabled and the internal prescaler is set to divide by 32768. If the
power-line frequency option is selected, the prescale value is set by FREQ_SEL, and the
32 kHz oscillator is disabled. See Table 51.
Table 51. Real Time Clock Control Register (RTC_CTRL = 00EDh)
Bit
7
6
5
4
3
2
1
0
Reset
X
0
X
X
X
X
0/1
0
CPU Access
R
R/W
R/W
R/W
R/W
R
R
R/W
Note: X = Unchanged by RESET; R = Read-only; R/W = Read/Write.
Bit
Position
7
ALARM
PS013015-0316
Value
Description
0
Alarm interrupt is inactive.
1
Alarm interrupt is active.
6
INT_EN
0
Interrupt on alarm condition is disabled.
1
Interrupt on alarm condition is enabled.
5
BCD_EN
0
RTC count and alarm value registers are binary.
1
RTC count and alarm value registers are binary-coded
decimal (BCD).
4
CLK_SEL
0
RTC clock source is crystal oscillator output (32768 Hz).
On-chip 32768 Hz oscillator is enabled.
1
RTC clock source is power-line frequency input.
On-chip 32768 Hz oscillator is disabled.
3
FREQ_SEL
0
Power-line frequency is 60 Hz.
1
Power-line frequency is 50 Hz.
2
0
Reserved.
1
SLP_WAKE
0
RTC does not generate a Sleep-Mode Recovery reset.
1
RTC Alarm generates a Sleep-Mode Recovery reset.
0
RTC_UNLOCK
0
RTC count registers are locked to prevent write access.
RTC counter is enabled.
1
RTC count registers are unlocked to allow write access.
RTC counter is disabled.
Real Time Clock Alarm
eZ80L92 MCU
Product Specification
104
Universal Asynchronous Receiver/
Transmitter
to eZ80 CPU
System Clock
I/O Address
Data
Interrupt Signal
UART Control Interface and Baud Rate Generator
The UART module implements the logic required to support various asynchronous
communications protocols. The module also implements two separate 16-byte-deep
FIFOs for both transmission and reception. A block diagram of the UART is illustrated
in Figure 23.
Receive
Buffer
RxD0/RxD1
Transmit
Buffer
TxD0/TxD1
Modem
Control
Logic
CTS0/CTS1
RTS0/RTS1
DSR0/DSR1
DTR0/DTR1
DCD0/DCD1
RI0/RI1
Figure 23. UART Block Diagram
The UART module provides the following asynchronous communication protocol-related
features and functions:
•
•
•
•
•
•
PS013015-0316
5-bit, 6-bit, 7-bit, or 8-bit data transmission
Even parity/odd parity or no parity bit generation and detection
Start and stop bit generation and detection (supports up to two stop bits)
Line break detection and generation
Receiver overrun and framing errors detection
Logic and associated I/O to provide modem handshake capability
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
105
UART Functional Description
The UART function implements the following:
•
•
•
The transmitter and associated control logic.
The receiver and associated control logic.
The modem interface and associated logic.
UART Transmitter
The transmitter block controls the data transmitted on the TxD output. It implements the
FIFO, accessed through the UARTx_THR register, the transmit shift register, the parity
generator, and control logic for the transmitter to control parameters for the asynchronous
communication protocol.
The UARTx_THR is a Write-Only register. The processor writes the data byte to be
transmitted into this register. In the FIFO mode, up to 16 data bytes can be written via the
UARTx_THR register. The data byte from the FIFO is transferred to the transmit shift
register at the appropriate time and transmitted out on TxD output. After SYNC_RESET,
the UARTx_THR register is empty. Therefore, the Transmit Holding Register Empty
(THRE) bit (bit 5 of the UARTx_LSR register) is 1 and an interrupt is sent to the
processor (if interrupts are enabled). The processor can reset this interrupt by loading
data into the UARTx_THR register, which clears the transmitter interrupt.
The transmit shift register places the byte to be transmitted on the TxD signal serially. The
least-significant bit of the byte to be transmitted is shifted out first and the most significant
bit is shifted out last. The control logic within the block adds the asynchronous communication protocol bits to the data byte being transmitted. The transmitter block obtains the
parameters for the protocol from the bits programmed via the UARTx_LCTL register.
The TxD output is set to 1 if the transmitter is idle (it does not contain any data to be
transmitted).
The transmitter operates with the Baud Rate Generator (BRG) clock. The data bits are
placed on the TxD output one time every 16 BRG clock cycles. The transmitter block also
implements a parity generator that attaches the parity bit to the byte, if programmed.
UART Receiver
The receiver block controls the data reception from the RxD signal. The receiver block
implements a receiver shift register, receiver line error condition monitoring logic and
receiver data ready logic. It also implements the parity checker.
The UARTx_RBR is a Read-Only register of the module. The processor reads received
data from this register. The condition of the UARTx_RBR register is monitored by the
DR bit (bit 0 of the UARTx_LSR register). The DR bit is 1 when a data byte is received
and transferred to the UARTx_RBR register from the receiver shift register. The DR bit
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
106
is reset only when the processor reads all of the received data bytes. If the number of bits
received is less than eight, the unused most significant bits of the data byte Read are 0.
The receiver uses the clock from the BRG for receiving the data. This clock must be 16
times the appropriate baud rate. The receiver synchronizes the shift clock on the falling
edge of the RxD input start bit. It then receives a complete byte according to the set
parameters. The receiver also implements logic to detect framing errors, parity errors,
overrun errors, and break signals.
UART Modem Control
The modem control logic provides two outputs and four inputs for handshaking with the
modem. Any change in the modem status inputs, except RI, is detected and an interrupt
can be generated. For RI, an interrupt is generated only when the trailing edge of the RI is
detected. The module also provides LOOP mode for self-diagnostics.
UART Interrupts
There are five different sources of interrupts from the UART are:
•
•
•
Transmitter.
Receiver (three different interrupts).
Modem status.
UART Transmitter Interrupt
The transmitter interrupt is generated if there is no data available for transmission. This
interrupt can be disabled using the individual interrupt enable bit or cleared by writing
data into the UARTx_THR register.
UART Receiver Interrupts
A receiver interrupt can be generated by three possible sources. The first source, a receiver
data ready, indicates that one or more data bytes are received and are ready to be read. This
interrupt is generated if the number of bytes in the receiver FIFO is greater than or equal to
the trigger level. If the FIFO is not enabled, the interrupt is generated if the receive buffer
contains a data byte. This interrupt is cleared by reading the UARTx_RBR.
The second interrupt source is the receiver time-out. A receiver time-out interrupt is generated when there are fewer data bytes in the receiver FIFO than the trigger level and there
are no Reads and Writes to or from the receiver FIFO for four consecutive byte times.
When the receiver time-out interrupt is generated, it is cleared only after emptying the
entire receive FIFO.
The first two interrupt sources from the receiver (data ready and time-out) share an
interrupt enable bit.
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
107
The third source of a receiver interrupt is a line status error, indicating an error in byte
reception. This error may result from:
•
•
•
•
Incorrect received parity.
Incorrect framing; that is, the stop bit is not detected by receiver at the end of the byte.
Receiver over run condition.
A BREAK condition being detected on the receive data input.
An interrupt due to one of the above conditions is cleared when the UARTx_LSR register
is read. In FIFO mode, a line status interrupt is generated only after the received byte with
an error reaches the top of the FIFO and is ready to be read.
A line status interrupt is activated (provided this interrupt is enabled) as long as the Read
pointer of the receiver FIFO points to the location of the FIFO that contains a byte with the
error. The interrupt is immediately cleared when the UARTx_LSR register is read. The
ERR bit of the UARTx_LSR register is active as long as an erroneous byte is present in the
receiver FIFO.
UART Modem Status Interrupt
The modem status interrupt is generated if there is any change in state of the modem status
inputs to the UART. This interrupt is cleared when the processor reads the UARTx_MSR
register.
UART Recommended Usage
The following is the standard sequence of events that occur in the ZLP12840 MCU using
the UART. A description of each follows.
1. Module reset.
2. Control transfers to configure UART operation.
3. Data transfers.
Module Reset. Upon reset, all internal registers are set to their default values. All com-
mand status registers are programmed with their default values, and the FIFOs are flushed.
Control Transfers. Based on the requirements of the application, the data transfer baud
rate is determined and the BRG is configured to generate a 16X clock frequency. Interrupts are disabled and the communication control parameters are programmed in the
UARTx_LCTL register. The FIFO configuration is determined and the receive trigger levels are set in the UARTx_FCTL register. The status registers, UARTx_LSR and
UARTx_MSR, are read, and ensure that none of the interrupt sources are active. The inter-
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
108
rupts are enabled (except for the transmit interrupt) and the application is ready to use the
module for transmission/reception.
Data Transfers—Transmit. To transmit data, the application enables the transmit interrupt. An interrupt is immediately expected in response. The application reads the
UARTx_IIR register and determines that the interrupt occurs due to an empty
UARTx_THR register. When the application determines this occurrence, the application
writes the transmit data bytes to the UARTx_THR register. The number of bytes that the
application writes depends on whether or not the FIFO is enabled. If the FIFO is enabled,
the application can write 16 bytes at a time. If not, the application can write one byte at a
time. As a result of the first Write, the interrupt is deactivated. The processor then waits
for the next interrupt. When the interrupt is raised by the UART module, the processor
repeats the same process until it exhausts all of the data for transmission.
To control and check the modem status, the application sets up the modem by writing to
the UARTx_MCTL register and reading the UARTx_MCTL register before starting the
process mentioned above.
Data Transfers—Receive. The receiver is always enabled, and it continually checks for
the start bit on the RxD input signal. When an interrupt is raised by the UART module, the
application reads the UARTx_IIR register and determines the cause for the interrupt. If the
cause is a line status interrupt, the application reads the UARTx_LSR register, reads the
data byte and then can discard the byte or take other appropriate action. If the interrupt is
caused by a receive-data-ready condition, the application alternately reads the
UARTx_LSR and UARTx_RBR registers and removes all of the received data bytes. It
reads the UARTx_LSR register before reading the UARTx_RBR register to determine that
there is no error in the received data.
To control and check modem status, the application sets up the modem by writing to the
UARTx_MCTL register and reading the UARTx_MSR register before starting the process
mentioned above.
Poll Mode Transfers. When interrupts are disabled, all data transfers are referred to as
poll mode transfers. In poll mode transfers, the application must continually poll the
UARTx_LSR register to transmit or receive data without enabling the interrupts. The
same holds true for the UARTx_MSR register. If the interrupts are not enabled, the data in
the UARTx_IIR register cannot be used to determine the cause of interrupt.
Baud Rate Generator
The Baud Rate Generator consists of a 16-bit downcounter, two registers, and associated
decoding logic. The initial value of the Baud Rate Generator is defined by the two BRG
Divisor Latch registers, {UARTx_BRG_H, UARTx_BRG_L}. At the rising edge of each
system clock, the BRG decrements until it reaches the value 0001h. On the next system
clock rising edge, the BRG reloads the initial value from {UARTx_BRG_H,
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
109
UARTx_BRG_L) and outputs a pulse to indicate the end-of-count. Calculate the UART
data rate with the following equation:
UART Data Rate (bps)
=
System Clock Frequency
16 x (UART Baud Rate Generator Divisor)
Upon RESET, the 16-bit BRG divisor value resets to 0002h. A minimum BRG divisor
value of 0001h is also valid, and effectively bypasses the BRG. A software Write to either
the Low- or High-byte registers for the BRG Divisor Latch causes both the Low and High
bytes to load into the BRG counter, and causes the count to restart.
The divisor registers can only be accessed if bit 7 of the UART Line Control register
(UARTx_LCTL) is set to 1. After reset, this bit is reset to 0.
Recommended Usage of the Baud Rate Generator
The following is the normal sequence of operations that should occur after the ZLP12840
MCU is powered on to configure the Baud Rate Generator:
•
•
•
Set UARTx_LCTL[7] to 1 to enable access of the BRG divisor registers
Program the UARTx_BRG_L and UARTx_BRG_H registers
Clear UARTx_LCTL[7] to 0 to disable access of the BRG divisor registers
BRG Control Registers
UART Baud Rate Generator Registers—Low and High Bytes
The registers hold the Low and High bytes of the 16-bit divisor count loaded by the processor for UART baud rate generation. The 16-bit clock divisor value is returned by
{UARTx_BRG_H, UARTx_BRG_L}, where x is either 0 or 1 to identify the two available
UART devices. On RESET, the 16-bit BRG divisor value resets to 0002h. The initial 16bit divisor value must be between 0002h and FFFFh as the values 0000h and 0001h are
invalid, and proper operation is not guaranteed. As a result, the minimum BRG clock divisor ratio is 2.
A Write to either the Low- or High-byte registers for the BRG Divisor Latch causes both
bytes to be loaded into the BRG counter. The count is then restarted.
Bit 7 of the associated UART Line Control register (UARTx_LCTL) must be set to 1 to
access this register. See Table 52 and Table 53. For more information, see UART Line
Control Registers (UARTx_LCTL) on page 115.
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
110
The UARTx_BRG_L registers share the same address space with the UARTx_RBR and
Note: UARTx_THR registers. The UARTx_BRG_H registers share the same address space with
the UARTx_IER registers. Bit 7 of the associated UART Line Control register
(UARTx_LCTL) must be set to 1 to enable access to the BRG registers.
Table 52. UART Baud Rate Generator Registers—Low Byte (UART0_BRG_L =
00C0h, UART1_BRG_L = 00D0h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R = Read only; R/W = Read/Write.
Bit
Position
[7:0]
UARTx_BRG_L
Value
Description
00h–FFh These bits represent the Low byte of the 16-bit Baud Rate
Generator divider value. The complete BRG divisor value
is returned by {UARTx_BRG_H, UARTx_BRG_L}.
Table 53. UART Baud Rate Generator Registers—High Byte (UART0_BRG_H =
00C1h, UART1_BRG_H = 00D1h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R = Read only; R/W = Read/Write.
Bit
Position
[7:0]
UARTx_BRG_H
Value
Description
00h–FFh These bits represent the High byte of the 16-bit Baud Rate
Generator divider value. The complete BRG divisor value is
returned by {UARTx_BRG_H, UARTx_BRG_L}.
UART Registers
After a RESET, all UART registers are set to their default values. Any Writes to unused
registers or register bits are ignored and Reads return a value of 0. For compatibility with
future revisions, unused bits within a register must be written with a value of 0. Read/
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
111
Write attributes, reset conditions, and bit descriptions of all of the UART registers are provided in this section.
UART Transmit Holding Registers
If less than eight bits are programmed for transmission, the lower bits of the byte written
to this register are selected for transmission. The transmit FIFO is mapped at this address.
You can write up to 16 bytes for transmission at one time to this address if the FIFO is
enabled by the application. If the FIFO is disabled, this buffer is only one byte deep.
These registers share the same address space as the UARTx_RBR and UARTx_BRG_L
registers. See Table 54.
Table 54. UART Transmit Holding Registers (UART0_THR = 00C0h, UART1_THR =
00D0h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write only.
Bit
Position
[7:0]
T xD
Value
Description
00h–FFh Transmit data byte.
UART Receive Buffer Registers
The bits in this register reflect the data received. If less than eight bits are programmed for
receive, the lower bits of the byte reflect the bits received whereas upper unused bits are 0.
The receive FIFO is mapped at this address. If the FIFO is disabled, this buffer is only one
byte deep.
These registers share the same address space as the UARTx_THR and UARTx_BRG_L
registers. See Table 55.
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
112
Table 55. UART Receive Buffer Registers (UART0_RBR = 00C0h, UART1_RBR =
00 D0h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
Bit
Position
[7:0]
RxD
Value
Description
00h–FFh
Receive data byte.
UART Interrupt Enable Registers
The UARTx_IER register is used to enable and disable the UART interrupts. The
UARTx_IER registers share the same I/O addresses as the UARTx_BRG_H registers. See
Table 56.
Table 56. UART Interrupt Enable Registers (UART0_IER = 00C1h, UART1_IER =
00D1h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R/W
R/W
R/W
R/W
Note: R = Read only.; R/W = Read/Write.
PS013015-0316
Bit
Position
Value Description
[7:4]
0000
3
MIIE
0
Modem interrupt on edge detect of status inputs is disabled.
1
Modem interrupt on edge detect of status inputs is enabled.
2
LSIE
0
Line status interrupt is disabled.
1
Line status interrupt is enabled for receive data errors:
incorrect parity bit received, framing error, overrun error, or
break detection.
Reserved
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
113
Bit
Position
Value Description
1
TIE
0
Transmit interrupt is disabled.
1
Transmit interrupt is enabled. Interrupt is generated when the
transmit FIFO/buffer is empty indicating no more bytes
available for transmission.
0
RIE
0
Receive interrupt is disabled.
1
Receive interrupt and receiver time-out interrupt are enabled.
Interrupt is generated if the FIFO/buffer contains data ready to
be read or if the receiver times out.
UART Interrupt Identification Registers
The Read-Only UARTx_IIR register allows you to check whether the FIFO is enabled and
the status of interrupts. These registers share the same I/O addresses as the UARTx_FCTL
registers. See Table 57 and Table 58.
Table 57. UART Interrupt Identification Registers (UART0_IIR = 00C2h, UART1_IIR
= 00D2h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
1
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
Bit
Position
Description
[7:6]
FSTS
00
FIFO is disabled.
11
FIFO is enabled.
[5:4]
00
Reserved
[3:1]
INSTS
0
INTBIT
PS013015-0316
Value
000–110 Interrupt Status Code
The code indicated in these three bits is valid only if INTBIT
is 0. If two internal interrupt sources are active and their
respective enable bits are High, only the higher priority
interrupt is seen by the application. The lower-priority
interrupt code is indicated only after the higher-priority
interrupt is serviced. Table 58 lists the interrupt status codes.
0
There is an active interrupt source within the UART.
1
There is not an active interrupt source within the UART.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
114
Table 58. UART Interrupt Status Codes
INSTS Value
Priority
Interrupt Type
011
Highest
Receiver Line Status
010
Second
Receive Data Ready or Trigger Level
110
Third
Character Time-out
001
Fourth
Transmit Buffer Empty
000
Lowest
Modem Status
UART FIFO Control Registers
This register is used to monitor trigger levels, clear FIFO pointers, and enable or disable
the FIFO. The UARTx_FCTL registers share the same I/O addresses as the UARTx_IIR
registers. See Table 59.
Table 59. UART FIFO Control Registers (UART0_FCTL = 00C2h, UART1_FCTL =
00D2h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write only.
Bit
Position
[7:6]
TRIG
[5:3]
PS013015-0316
Value Description
00
Receive FIFO trigger level set to 1. Receive data interrupt is
generated when there is 1 byte in the FIFO. Valid only if FIFO
is enabled.
01
Receive FIFO trigger level set to 4. Receive data interrupt is
generated when there are 4 bytes in the FIFO. Valid only if
FIFO is enabled.
10
Receive FIFO trigger level set to 8. Receive data interrupt is
generated when there are 8 bytes in the FIFO. Valid only if
FIFO is enabled.
11
Receive FIFO trigger level set to 14. Receive data interrupt is
generated when there are 14 bytes in the FIFO. Valid only if
FIFO is enabled.
000
Reserved.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
115
Bit
Position
Value Description
2
CLRTXF
0
No effect.
1
Clear the transmit FIFO and reset the transmit FIFO pointer.
Valid only if the FIFO is enabled.
1
CLRRXF
0
No effect.
1
Clear the receive FIFO, clear the receive error FIFO, and reset
the receive FIFO pointer. Valid only if the FIFO is enabled.
0
FIFOEN
0
Transmit and receive FIFOs are disabled. Transmit and receive
buffers are only 1 byte deep.
1
Transmit and receive FIFOs are enabled.
UART Line Control Registers
This register is used to control the communication control parameters. See Table 60 and
Table 61.
Table 60. UART Line Control Registers (UART0_LCTL = 00C3h, UART1_LCTL =
00D3h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
7
DLAB
PS013015-0316
Value Description
0
Access to the UART registers at I/O addresses UARTx_RBR,
UARTx_THR, and UARTx_IER is enabled.
1
Access to the Baud Rate Generator registers at I/O addresses
UARTx_BRG_L and UARTx_BRG_H is enabled.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
116
Bit
Position
6
SB
0
Do not send a BREAK signal.
1
Send Break
UART sends continuous zeroes on the transmit output from the
next bit boundary. The transmit data in the transmit shift
register is ignored. After forcing this bit High, the TxD output is
0 only after the bit boundary is reached. Just before forcing
TxD to 0, the transmit FIFO is cleared. Any new data written to
the transmit FIFO during a break should be written only after
the THRE bit of UARTx_LSR register goes High. This new data
is transmitted after the UART recovers from the break. After the
break is removed, the UART recovers from the break for the
next BRG edge.
5
FPE
0
Do not force a parity error.
1
Force a parity error. When this bit and the party enable bit
(PEN) are both 1, an incorrect parity bit is transmitted with the
data byte.
4
EPS
0
Use odd parity for transmission. The total number of 1 bits in
the transmit data plus parity bit is odd.
1
Use even parity for transmission. The total number of 1 bits in
the transmit data plus parity bit is even.
0
Parity bit transmit and receive is disabled.
1
Parity bit transmit and receive is enabled. For transmit, a parity
bit is generated and transmitted with every data character. For
receive, the parity is checked for every incoming data
character.
3
PEN
[2:0]
CHAR
PS013015-0316
Value Description
000–111 UART Character Parameter Selection
See Table 61 for a description of the values.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
117
Table 61. UART Character Parameter Definition
CHAR[2:0]
Character Length
(Tx/Rx Data Bits)
Stop Bits
(Tx Stop Bits)
000
5
1
001
6
1
010
7
1
011
8
1
100
5
2
101
6
2
110
7
2
111
8
2
UART Modem Control Registers
This register is used to control and check the modem status. See Table 62.
Table 62. UART Modem Control Registers (UART0_MCTL = 00C4h, UART1_MCTL =
00D4h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R/W
R/W
R/W
R/W
R/W
Note: R = Read only.; R/W = Read/Write.
Bit
Position
Value Description
[7:5]
000b
4
LOOP
PS013015-0316
Reserved.
0
LOOP BACK mode is not enabled.
1
LOOP BACK mode is enabled.
The UART operates in internal LOOP BACK mode. The
transmit data output port is disconnected from the internal
transmit data output and set to 1. The receive data input port is
disconnected and internal receive data is connected to internal
transmit data. The modem status input ports are disconnected
and the four bits of the modem control register are connected
as modem status inputs. The two modem control output ports
(OUT1&2) are set to their inactive state
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
118
Bit
Position
Value Description
3
OUT2
0–1
No function in normal operation.
In LOOP BACK mode, this bit is connected to the DCD bit in
the UART Status Register.
2
OUT1
0–1
No function in normal operation.
In LOOP BACK mode, this bit is connected to the RI bit in the
UART Status Register.
1
RTS
0–1
Request to Send.
In normal operation, the RTS output port is the inverse of this
bit. In LOOP BACK mode, this bit is connected to the CTS bit in
the UART Status Register.
0
DTR
0–1
Data Terminal Ready.
In normal operation, the DTR output port is the inverse of this
bit. In LOOP BACK mode, this bit is connected to the DSR bit
in the UART Status Register.
UART Line Status Registers
This register is used to show the status of UART interrupts and registers. See Table 63.
Table 63. UART Line Status Registers (UART0_LSR = 00C5h, UART1_LSR = 00 D5h)
Bit
7
6
5
4
3
2
1
0
Reset
0
1
1
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
Bit
Position
7
ERR
PS013015-0316
Value Description
0
Always 0 when operating with the FIFO disabled. With the
FIFO enabled, this bit is reset when the UARTx_LSR register is
read and there are no more bytes with error status in the FIFO.
1
Error detected in the FIFO. There is at least 1 parity, framing or
break indication error in the FIFO.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
119
Bit
Position
6
TEMT
0
Transmit holding register/FIFO is not empty or transmit shift
register is not empty or transmitter is not idle.
1
Transmit holding register/FIFO and transmit shift register are
empty; and the transmitter is idle. This bit cannot be set to 1
during the BREAK condition. This bit only becomes 1 after the
BREAK command is removed.
5
THRE
0
Transmit holding register/FIFO is not empty.
1
Transmit holding register/FIFO is empty. This bit cannot be set
to 1 during the BREAK condition. This bit only becomes 1 after
the BREAK command is removed.
4
BI
0
Receiver does not detect a BREAK condition. This bit is reset
to 0 when the UARTx_LSR register is read.
1
Receiver detects a BREAK condition on the receive input line.
This bit is 1 if the duration of BREAK condition on the receive
data is longer than one character transmission time, the time
depends on the programming of the UARTx_LSR register. In
case of FIFO only one null character is loaded into the receiver
FIFO with the framing error. The framing error is revealed to
the eZ80 whenever that particular data is read from the
receiver FIFO.
0
No framing error detected for character at the top of the FIFO.
This bit is reset to 0 when the UARTx_LSR register is read.
1
Framing error detected for the character at the top of the FIFO.
This bit is set to 1 when the stop bit following the data/parity bit
is logic 0.
0
The received character at the top of the FIFO does not contain
a parity error. This bit is reset to 0 when the UARTx_LSR
register is read.
1
The received character at the top of the FIFO contains a parity
error.
3
FE
2
PE
PS013015-0316
Value Description
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
120
Bit
Position
Value Description
1
OE
0
DR
0
The received character at the top of the FIFO does not contain
an overrun error. This bit is reset to 0 when the UARTx_LSR
register is read.
1
Overrun error is detected. If the FIFO is not enabled, this
indicates that the data in the receive buffer register was not
read before the next character was transferred into the receiver
buffer register. If the FIFO is enabled, this indicates the FIFO
was already full when an additional character was received by
the receiver shift register. The character in the receiver shift
register is not put into the receiver FIFO.
0
This bit is reset to 0 when the UARTx_RBR register is read or
all bytes are read from the receiver FIFO.
1
Data ready. If the FIFO is not enabled, this bit is set to 1 when
a complete incoming character is transferred into the receiver
buffer register from the receiver shift register. If the FIFO is
enabled, this bit is set to 1 when a character is received and
transferred to the receiver FIFO.
UART Modem Status Registers
This register is used to show the status of the UART signals. See Table 64.
Table 64. UART Modem Status Registers (UART0_MSR = 00C6h, UART1_MSR =
00 D6h)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
PS013015-0316
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
121
Bit
Position
PS013015-0316
Value Description
7
DCD
0–1
Data Carrier Detect
In NORMAL mode, this bit reflects the inverted state of the
DCDx input pin. In LOOP BACK mode, this bit reflects the
value of the UARTx_MCTL[3] = out2.
6
RI
0–1
Ring Indicator
In NORMAL mode, this bit reflects the inverted state of the RIx
input pin. In LOOP BACK mode, this bit reflects the value of the
UARTx_MCTL[2] = out1.
5
DSR
0–1
Data Set Ready
In NORMAL mode, this bit reflects the inverted state of the
DSRx input pin. In LOOP BACK mode, this bit reflects the
value of the UARTx_MCTL[0] = DTR.
4
CTS
0–1
Clear to Send
In NORMAL mode, this bit reflects the inverted state of the
CTSx input pin. In LOOP BACK mode, this bit reflects the value
of the UARTx_MCTL[1] = RTS.
3
DDCD
0–1
Delta Status Change of DCD
This bit is set to 1 whenever the DCDx pin changes state. This
bit is reset to 0 when the UARTx_MSR register is read.
2
TERI
0–1
Trailing Edge Change on RI.
This bit is set to 1 whenever a falling edge is detected on the
RIx pin. This bit is reset to 0 when the UARTx_MSR register is
read.
1
DDSR
0–1
Delta Status Change of DSR
This bit is set to 1 whenever the DSRx pin changes state. This
bit is reset to 0 when the UARTx_MSR register is read.
0
DCTS
0–1
Delta Status Change of CTS
This bit is set to 1 whenever the CTSx pin changes state.
This bit is reset to 0 when the UARTx_MSR register is read.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
122
UART Scratch Pad Registers
The UARTx_SPR register can be used by the system as a general-purpose Read/Write
register. See Table 65.
Table 65. UART Scratch Pad Registers (UART0_SPR = 00C7h, UART1_SPR =
00D7h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
SPR
PS013015-0316
Value
Description
00h–FFh UART scratch pad register is available for use as a
general-purpose Read/Write register.
Universal Asynchronous Receiver/Transmitter
eZ80L92 MCU
Product Specification
123
Infrared Encoder/Decoder
The ZLP12840 MCU contains a UART to infrared encoder/decoder (endec). The infrared
encoder/decoder is integrated with the on-chip UART0 to allow easy communication
between the eZ80 CPU and IrDA Physical Layer Specification Version 1.3 compliant
infrared transceivers as illustrated in Figure 24. Infrared communication provides secure,
reliable, high-speed, low-cost, and point-to-point communication between PCs, PDAs,
mobile telephones, printers, and other infrared enabled devices.
eZ80L92
Infrared
Transceiver
System
Clock
RxD
TxD
UART0
Baud Rate
Clock
Interrupt
I/O
Signal Address
Data
IR_RxD
Infrared
Encoder/Decoder
IR_TxD
RxD
TxD
I/O
Data
Address
To eZ80 CPU
Figure 24. Infrared System Block Diagram
Functional Description
When the infrared encoder/decoder is enabled, the transmit data from the on-chip UART
is encoded as digital signals in accordance with the IrDA standard and output to the
infrared transceiver. Likewise, data received from the infrared transceiver is decoded by
the infrared encoder/decoder and passed to the UART. Communication is half-duplex
meaning that simultaneous data transmission and reception is not allowed.
The baud rate is set by the UART Baud Rate Generator and supports IrDA standard baud
rates from 9600 bps to 115.2 Kbps. Higher baud rates are possible, but do not meet IrDA
specifications. The UART must be enabled to use the infrared encoder/decoder.
PS013015-0316
Infrared Encoder/Decoder
eZ80L92 MCU
Product Specification
124
For more information on the UART and its Baud Rate Generator, see Universal Asynchronous Receiver/Transmitter on page 104.
Transmit
The data to be transmitted via the IR transceiver is first sent to UART0. The UART
transmit signal (TxD) and Baud Rate Clock are used by the infrared encoder/decoder to
generate the modulation signal (IR_TXD) that drives the infrared transceiver. Each UART
bit is 16-clocks wide. If the data to be transmitted is a logical 1 (High), the IR_TXD signal
remains Low (0) for the full 16-clock period. If the data to be transmitted is a logical 0, a
3-clock High (1) pulse is output following a 7-clock Low (0) period. Following the
3-clock High pulse, a 6-clock Low pulse completes the full 16-clock data period. Data
transmission is illustrated in Figure 25. During data transmission, the IR receive function
should be disabled by clearing the IR_RXEN bit in the IR_CTL reg to 0. This prevents
transmitter to receiver cross-talk.
16-clock
period
Baud Rate
Clock
UART_TxD
Start Bit = 0
Data Bit 0 = 1
Data Bit 1 = 0
Data Bit 2 = 1
Data Bit 3 = 1
3-clock
pulse
IR_TxD
7-clock
delay
Figure 25. Infrared Data Transmission
Receive
Data received from the IR transceiver via the IR_RXD signal is decoded by the infrared
encoder/decoder and passed to the UART. The IR_RXEN bit in the IR_CTL register must
be set to enable the receiver decoder. The SIR data format uses half duplex communication therefore the UART should not be allowed to transmit while the receiver decoder is
enabled. The UART Baud Rate Clock is used by the infrared encoder/decoder to generate
the demodulated signal (RxD) that drives the UART. Each UART bit is 16-clocks wide. If
the data to be received is a logical 1 (High), the IR_RXD signal remains High (1) for the
full 16-clock period. If the data to be received is a logical 0, a 3-clock Low (0) pulse is
PS013015-0316
Infrared Encoder/Decoder
eZ80L92 MCU
Product Specification
125
output following a 7-clock High (1) period. Following the 3-clock Low pulse, is a 6-clock
High pulse to complete the full 16-clock data period. Data transmission is illustrated in
Figure 26.
16-clock
period
Baud Rate
Clock
Start Bit = 0
Data Bit 0 = 1
Data Bit 1 = 0
Data Bit 2 = 1
Data Bit 3 = 1
IR_RxD
1.6 s
min. pulse
UART_RxD
8-clock
delay
16-clock
period
16-clock
period
16-clock
period
16-clock
period
Figure 26. Infrared Data Reception
Jitter
Due to the inherent sampling of the received IR_RXD signal by the BIt Rate Clock, some
jitter can be expected on the first bit in any sequence of data. However, all subsequent bits
in the received data stream are a fixed 16-clock periods wide.
Infrared Encoder/Decoder Signal Pins
The infrared encoder/decoder signal pins (IR_TXD and IR_RXD) are multiplexed with
General-Purpose I/O (GPIO) pins. These GPIO pins must be configured for alternate function operation for the infrared encoder/decoder to operate.
The remaining six UART0 pins (CTS0, DCD0, DSR0, DTR0, RTS0 and RI0) are not
required for use with the infrared encoder/decoder. The UART0 modem status interrupt
should be disabled to prevent unwanted interrupts from these pins. The GPIO pins corresponding to these six unused UART0 pins can be used for inputs, outputs, or interrupt
sources. Recommended GPIO Port D control register settings are listed in Table 66. For
additional information on setting the GPIO Port modes, see General-Purpose Input/Output
on page 38
PS013015-0316
Infrared Encoder/Decoder
eZ80L92 MCU
Product Specification
126
Table 66. GPIO Mode Selection while using the IrDA Encoder/Decoder
GPIO Port D Bits
Allowable GPIO
Port Mode
Allowable Port Mode Functions
PD0
7
Alternate Function
PD1
7
Alternate Function
PD2–PD7
Any other than GPIO Mode 7
(1, 2, 3, 4, 5, 6, 8, or 9)
Output, Input, Open-Drain, Open-Source,
Level-sensitive Interrupt Input, or EdgeTriggered Interrupt Input
Loopback Testing
Both internal and external loopback testing can be accomplished with the endec on the
ZLP12840 MCU. Internal loopback testing is enabled by setting the LOOP_BACK bit to
1. During internal loopback, IR_TXD output signal is inverted and connected on-chip to the
IR_RXD input. External loopback testing of the off-chip IrDA transceiver may be accomplished by transmitting data from the UART while the receiver is enabled (IR_RXEN set
to 1).
Infrared Encoder/Decoder Register
After a RESET, the infrared encoder/decoder register is set to its default value. Any Writes
to unused register bits are ignored and Reads return a value of 0. Unused bits within a register must always be written with a value of 0. The IR_CTL register is described in
Table 67.
Table 67. Infrared Encoder/Decoder Control Register (IR_CTL = 00BFh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R = Read only; R/W = Read/Write.
Bit
Position
[7:3]
2
LOOP_BACK
PS013015-0316
Value
000000
Description
Reserved.
0
Internal LOOP BACK mode is disabled.
1
Internal LOOP BACK mode is enabled.
IR_TXD output is inverted and connected to IR_RXD input for
internal loop back testing.
Infrared Encoder/Decoder
eZ80L92 MCU
Product Specification
127
Bit
Position
PS013015-0316
Value
Description
1
IR_RXEN
0
IR_RXD data is ignored.
1
IR_RXD data is passed to UART0 RxD.
0
IR_EN
0
Infrared Encoder/Decoder is disabled.
1
Infrared Encoder/Decoder is enabled.
Infrared Encoder/Decoder
eZ80L92 MCU
Product Specification
128
Serial Peripheral Interface
The Serial Peripheral Interface (SPI) is a synchronous interface allowing several SPI-type
devices to be interconnected. The SPI is a full-duplex, synchronous, and characteroriented communication channel that employs a four-wire interface. The SPI block consists of a transmitter, receiver, baud rate generator, and control unit. During an SPI transfer, data is sent and received simultaneously by both the master and the slave SPI devices.
In a serial peripheral interface, separate signals are required for data and clock. The SPI
may be configured as either a master or a slave. The connection of two SPI devices (one
master and one slave) and the direction of data transfer is demonstrated in Figure 27 and
Figure 28.
MASTER
SS
DATAIN
MISO
Bit 7
Bit 0
8-Bit Shift Register
DATAOUT
SCK
CLKOUT
Baud Rate
Generator
Figure 27. SPI Master Device
SLAVE
ENABLE
SS
DATAIN
MOSI
CLKIN
SCK
Bit 0
Bit 7
MISO
DATAOUT
8-Bit Shift Register
Figure 28. SPI Slave Device
PS013015-0316
Serial Peripheral Interface
eZ80L92 MCU
Product Specification
129
SPI Signals
The four basic SPI signals are:
•
•
•
•
MISO (Master-In/Slave-Out)
MOSI (Master-Out/Slave-In)
SCK (SPI Serial Clock)
SS (Slave Select)
The following section describes the SPI signals. Each signal is described in both
MASTER and SLAVE modes.
Master-In, Slave-Out
The Master-In/Slave-Out (MISO) pin is configured as an input in a master device and as
an output in a slave device. It is one of the two lines that transfer serial data, with the most
significant bit sent first. The MISO pin of a slave device is placed in a high-impedance
state if the slave is not selected. When the SPI is not enabled, this signal is in a highimpedance state.
Master-Out, Slave-In
The Master-Out/Slave-In (MOSI) pin is configured as an output in a master device and as
an input in a slave device. It is one of the two lines that transfer serial data, with the most
significant bit sent first. When the SPI is not enabled, this signal is in a high-impedance
state.
Slave Select
The active Low Slave Select (SS) input signal is used to select the SPI as a slave device. It
must be Low prior to all data communication and must stay Low for the duration of the
data transfer.
The SS input signal must be High for the SPI to operate as a master device. If the SS signal
goes Low, a Mode Fault error flag (MODF) is set in the SPI_SR register. See the SPI Status Register (SPI_SR) on page 136 for more information.
When the clock phase (CPHA) is set to 0, the shift clock is the logical OR of SS with
SCK. In this clock phase mode, SS must go High between successive characters in an SPI
message. When CPHA is set to 1, SS can remain Low for several SPI characters. In cases
where there is only one SPI slave, its SS line could be tied Low as long as CPHA is set to
1. See the SPI Control Register (SPI_CTL) on page 135 for more information about
CPHA.
PS013015-0316
Serial Peripheral Interface
eZ80L92 MCU
Product Specification
130
Serial Clock
The Serial Clock (SCK) is used to synchronize data movement both in and out of the
device through its MOSI and MISO pins. The master and slave are capable of exchanging
a data byte during a sequence of eight clock cycles. As SCK is generated by the master,
the SCK pin becomes an input on a slave device. The SPI contains an internal divide-bytwo clock divider. In MASTER mode, the SPI serial clock is one-half the frequency of the
clock signal created by the SPI’s Baud Rate Generator.
As demonstrated in Figure 29 and Table 68, four possible timing relations may be chosen
by using control bits CPOL and CPHA in the SPI Control register. See the SPI Control
Register (SPI_CTL) on page 135. Both the master and slave must operate with the identical timing, Clock Polarity (CPOL), and Clock Polarity (CPHA). The master device always
places data on the MOSI line a half-cycle before the clock edge (SCK signal), in order for
the slave device to latch the data.
PS013015-0316
Serial Peripheral Interface
eZ80L92 MCU
Product Specification
131
Number of Cycles on the SCK Signal
1
2
3
4
5
6
7
8
SCK (CPOL bit = 0)
SCK (CPOL bit = 1)
Sample Input
(CPHA bit = 0) Data Out
MSB
Sample Input
(CPHA bit = 1) Data Out
6
5
MSB
6
4
5
3
4
2
1
3
2
LSB
1
LSB
Enable (To Slave)
Figure 29. SPI Timing
Table 68. SPI Clock Phase and Clock Polarity Operation
CPHA
CPOL
SCK
Transmit
Edge
SCK
Receive
Edge
SCK
Idle
State
SS High
Between
Characters?
0
0
Falling
Rising
Low
Yes
0
1
Rising
Falling
High
Yes
1
0
Rising
Falling
Low
No
1
1
Falling
Rising
High
No
SPI Functional Description
When a master transmits to a slave device via the MOSI signal, the slave device responds
by sending data to the master via the master's MISO signal. The resulting implication is a
full-duplex transmission, with both data out and data in synchronized with the same clock
signal. Thus the byte transmitted is replaced by the byte received and eliminates the
requirement for separate transmit-empty and receive-full status bits. A single status bit,
SPIF, is used to signify that the I/O operation is completed, see SPI Status Register
(SPI_SR) on page 136.
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The SPI is double-buffered on Read, but not on Write. If a Write is performed during data
transfer, the transfer occurs uninterrupted, and the Write is unsuccessful. This condition
causes the WRITE COLLISION (WCOL) status bit in the SPI_SR register to be set. After
a data byte is shifted, the SPIF flag of the SPI_SR register is set.
In SPI MASTER mode, the SCK pin is an output. It idles High or Low, depending on the
CPOL bit in the SPI_CTL register, until data is written to the shift register. Data transfer is
initiated by writing to the transmit shift register, SPI_TSR. Eight clocks are then generated
to shift the eight bits of transmit data out the MOSI pin while shifting in eight bits of data
on the MISO pin. After transfer, the SCK signal idles.
In SPI SLAVE mode, the start logic receives a logic Low from the SS pin and a clock
input at the SCK pin, and the slave is synchronized to the master. Data from the master is
received serially from the slave MOSI signal and loads the 8-bit shift register. After the 8bit shift register is loaded, its data is parallel transferred to the Read buffer. During a Write
cycle data is written into the shift register, then the slave waits for the SPI master to initiate
a data transfer, supply a clock signal, and shift the data out on the slave's MISO signal.
If the CPHA bit in the SPI_CTL register is 0, a transfer begins when SS pin signal goes
Low and the transfer ends when SS goes High after eight clock cycles on SCK. When the
CPHA bit is set to 1, a transfer begins the first time SCK becomes active while SS is Low
and the transfer ends when the SPIF flag gets set.
SPI Flags
Mode Fault
The Mode Fault flag (MODF) indicates that there may be a multimaster conflict for system control. The MODF bit is normally cleared to 0 and is only set to 1 when the master
device’s SS pin is pulled Low. When a mode fault is detected, the following occurs:
1. The MODF flag (SPI_SR[4]) is set to 1.
2. The SPI device is disabled by clearing the SPI_EN bit (SPI_CTL[5]) to 0.
3. The MASTER_EN bit (SPI_CTL[4]) is cleared to 0, forcing the device into SLAVE
mode.
4. If the SPI interrupt is enabled by setting IRQ_EN (SPI_CTL[7]) High, an SPI interrupt is generated.
Clearing the Mode Fault flag is performed by reading the SPI Status register. The other
SPI control bits (SPI_EN and MASTER_EN) must be restored to their original states by
user software after the Mode Fault flag is cleared.
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Write Collision
The WRITE COLLISION flag, WCOL (SPI_SR[5]), is set to 1 when an attempt is made
to write to the SPI Transmit Shift register (SPI_TSR) while data transfer occurs. Clearing
the WCOL bit is performed by reading SPI_SR with the WCOL bit set.
SPI Baud Rate Generator
The SPI’s Baud Rate Generator creates a lower frequency clock from the high-frequency
system clock. The Baud Rate Generator output is used as the clock source by the SPI.
Baud Rate Generator Functional Description
The SPI’s Baud Rate Generator consists of a 16-bit downcounter, two 8-bit registers, and
associated decoding logic. The Baud Rate Generator’s initial value is defined by the two
BRG Divisor Latch registers, {SPI_BRG_H, SPI_BRG_L}. At the rising edge of each
system clock, the BRG decrements until it reaches the value 0001h. On the next system
clock rising edge, the BRG reloads the initial value from {SPI_BRG_H, SPI_BRG_L) and
outputs a pulse to indicate the end-of-count. Calculate the SPI Data Rate with the following equation:
System Clock Frequency
SPI Data Rate (bps)
=
2 X SPI Baud Rate Generator
Divisor
Upon RESET, the 16-bit BRG divisor value resets to 0002h. When the SPI is operating as
a Master, the BRG divisor value must be set to a value of 0003h or greater. When the SPI
is operating as a Slave, the BRG divisor value must be set to a value of 0004h or greater.
A software Write to either the Low- or High-byte registers for the BRG Divisor Latch
causes both the Low and High bytes to load into the BRG counter, and causes the count to
restart.
Data Transfer Procedure with SPI Configured as the Master
Follow the steps below for data transfer with SPI configured as the master:
1. Load the SPI Baud Rate Generator Registers, SPI_BRG_H and SPI_BRG_L.
2. External device must de-assert the SS pin if currently asserted.
3. Load the SPI Control Register, SPI_CTL.
4. Assert the ENABLE pin of the slave device using a GPIO pin.
5. Load the SPI Transmit Shift Register, SPI_TSR.
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6. When the SPI data transfer is complete, de-assert the ENABLE pin of the slave
device.
Data Transfer Procedure with SPI Configured as a Slave
Follow the steps below for data transfer with SPI configured as the slave:
1. Load the SPI Baud Rate Generator Registers, SPI_BRG_H and SPI_BRG_L.
2. Load the SPI Transmit Shift Register, SPI_TSR. This load cannot occur while the SPI
slave is currently receiving data.
3. Wait for the external SPI Master device to initiate the data transfer by asserting SS.
SPI Registers
There are six registers in the Serial Peripheral Interface which provide control, status, and
data storage functions. The SPI registers are described in the following section.
SPI Baud Rate Generator Registers—Low Byte and High Byte
These registers hold the Low and High bytes of the 16-bit divisor count loaded by the
processor for baud rate generation. The 16-bit clock divisor value is returned by
{SPI_BRG_H, SPI_BRG_L}. Upon RESET, the 16-bit BRG divisor value resets to
0002h. When configured as a Master, the 16-bit divisor value must be between 0003h
and FFFFh, inclusive. When configured as a Slave, the 16-bit divisor value must be
between 0004h and FFFFh, inclusive.
A Write to either the Low or High byte registers for the BRG Divisor Latch causes both
bytes to be loaded into the BRG counter and the count restarted. See Table 69 and
Table 70.
Table 69. SPI Baud Rate Generator Register—Low Byte (SPI_BRG_L = 00B8h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
SPI_BRG_L
PS013015-0316
Value
00h–FFh
Description
These bits represent the Low byte of the 16-bit Baud Rate
Generator divider value. The complete BRG divisor value is
returned by {SPI_BRG_H, SPI_BRG_L}.
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Table 70. SPI Baud Rate Generator Register—High Byte (SPI_BRG_H = 00B9h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
SPI_BRG_H
Value
Description
00h–FFh These bits represent the High byte of the 16-bit Baud Rate
Generator divider value. The complete BRG divisor value is
returned by {SPI_BRG_H, SPI_BRG_L}.
SPI Control Register
This register is used to control and setup the serial peripheral interface. The SPI must be
disabled prior to making any changes to CPHA or CPOL. See Table 71.
Table 71. SPI Control Register (SPI_CTL = 00BAh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
1
0
0
R/W
R
R/W
R/W
R/W
R/W
R
R
CPU Access
Note: R = Read Only; R/W = Read/Write.
Bit
Position
PS013015-0316
Value Description
7
IRQ_EN
0
SPI system interrupt is disabled.
1
SPI system interrupt is enabled.
6
0
Reserved.
5
SPI_EN
0
SPI is disabled.
1
SPI is enabled.
4
MASTER_EN
0
When enabled, the SPI operates as a slave.
1
When enabled, the SPI operates as a master.
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Product Specification
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Bit
Position
Value Description
3
CPOL
0
Master SCK pin idles in a Low (0) state.
1
Master SCK pin idles in a High (1) state.
2
CPHA
0
SS must go High after transfer of every byte of data.
1
SS can remain Low to transfer any number of data bytes.
[1:0]
00
Reserved.
SPI Status Register
The SPI Status Read-Only register returns the status of data transmitted using the serial
peripheral interface. Reading the SPI_SR register clears Bits 7, 6, and 4 to a logical 0.
See Table 72.
Table 72. SPI Status Register (SPI_SR = 00BBh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read Only
Bit
Position
Description
7
SPIF
0
SPI data transfer is not finished.
1
SPI data transfer is finished. If enabled, an interrupt is
generated. This bit flag is cleared to 0 by a Read of the
SPI_SR register.
6
WCOL
0
An SPI write collision is not detected.
1
An SPI write collision is detected. This bit flag is cleared to
0 by a Read of the SPI_SR registers.
5
0
Reserved.
4
MODF
0
A mode fault (multimaster conflict) is not detected.
1
A mode fault (multimaster conflict) is detected. This bit flag
is cleared to 0 by a Read of the SPI_SR register.
[3:0]
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Value
0000
Reserved.
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SPI Transmit Shift Register
The SPI Transmit Shift register (SPI_TSR) is used by the SPI master to transmit data onto
the SPI serial bus to the slave device. A Write to the SPI_TSR register places data directly
into the shift register for transmission. A Write to this register within an SPI device
configured as a master initiates transmission of the byte of the data loaded into the register.
At the completion of transmitting a byte of data, the SPIF status bit (SPI_SR[7]) is set to 1
in both the master and slave devices.
The SPI Transmit Shift Write-Only register shares the same address space as the SPI
Receive Buffer Read-Only register. See Table 73.
Table 73. SPI Transmit Shift Register (SPI_TSR = 00BCh)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: W= Write Only.
Bit
Position
[7:0]
TX_DATA
Value
Description
00h–FFh SPI transmit data.
SPI Receive Buffer Register
The SPI Receive Buffer register (SPI_RBR) is used by the SPI slave to receive data from
the serial bus. The SPIF bit must be cleared prior to a second transfer of data from the shift
register or an overrun condition exists. In cases of overrun, the byte that caused the overrun is lost.
The SPI Receive Buffer Read-Only register shares the same address space as the SPI
Transmit Shift Write-Only register. See Table 74.
Table 74. SPI Receive Buffer Register (SPI_RBR = 00BCh)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read Only
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Bit
Position
[7:0]
RX_DATA
PS013015-0316
Value
Description
00h–FFh SPI received data.
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I2C Serial I/O Interface
General Characteristics
The I2C serial I/O bus is a two-wire communication interface that can operate in four
modes:
•
•
•
•
MASTER TRANSMIT
MASTER RECEIVE
SLAVE TRANSMIT
SLAVE RECEIVE
The I2C interface consists of the Serial Clock (SCL) and the Serial Data (SDA). Both SDA
and SCL are bidirectional lines, connected to a positive supply voltage via an external
pull-up resistor. When the bus is free, both lines are High. The output stages of devices
connected to the bus must be configured as open-drain outputs. Data on the I2C bus can be
transferred at a rate of up to 100 Kbps in STANDARD mode, or up to 400 Kbps in FAST
mode. One clock pulse is generated for each data bit transferred.
Clocking Overview
If another device on the I2C bus drives the clock line when the I2C is in MASTER mode,
the I2C synchronizes its clock to the I2C bus clock. The High period of the clock is
determined by the device that generates the shortest High clock period. The Low period of
the clock is determined by the device that generates the longest Low clock period.
A slave may stretch the Low period of the clock to slow down the bus master. The Low
period may also be stretched for handshaking purposes. This can be done after each bit
transfer or each byte transfer. The I2C stretches the clock after each byte transfer until the
IFLG bit in the I2C_CTL register is cleared.
Bus Arbitration Overview
In MASTER mode, the I2C checks that each transmitted logic 1 appears on the I2C bus as
a logic 1. If another device on the bus overrules and pulls the SDA signal Low, arbitration
is lost. If arbitration is lost during the transmission of a data byte or a Not-Acknowledge
bit, the I2C returns to the idle state. If arbitration is lost during the transmission of an
address, the I2C switches to SLAVE mode so that it can recognize its own slave address or
the general call address.
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Data Validity
The data on the SDA line must be stable during the High period of the clock. The High or
Low state of the data line can only change when the clock signal on the SCL line is Low as
illustrated in Figure 30.
A Signal
L Signal
Data Line
Stable
Data Valid
Change of
Data Allowed
Figure 30. I2C Clock and Data Relationship
START and STOP Conditions
Within the I2C bus protocol, unique situations arise which are defined as START and
STOP conditions. See Figure 31. A High-to-Low transition on the SDA line while SCL is
High indicates a START condition. A Low-to-High transition on the SDA line while SCL
is High defines a STOP condition.
START and STOP conditions are always generated by the master. The bus is considered to
be busy after the START condition. The bus is considered to be free a defined time after
the STOP condition.
SDA Signal
SCL Signal
S
P
START Condition
STOP Condition
Figure 31. START and STOP Conditions In I2C Protocol
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Transferring Data
Byte Format
Every character transferred on the SDA line must be a single 8-bit byte. The number of
bytes that can be transmitted per transfer is unrestricted. Each byte must be followed by an
Acknowledge (ACK)1. Data is transferred with the most significant bit (msb) first. See
Figure 32. A receiver can hold the SCL line Low to force the transmitter into a wait state.
Data transfer then continues when the receiver is ready for another byte of data and
releases SCL.
SDA Signal
MSB
SCL Signal
1
Acknowledge from
Receiver
2
8
9
Acknowledge from
Receiver
1
S
START Condition
9
ACK
P
STOP Condition
Clock Line Held Low By Receiver
Figure 32. I2C Frame Structure
Acknowledge
Data transfer with an ACK function is obligatory. The ACK-related clock pulse is generated by the master. The transmitter releases the SDA line (High) during the ACK clock
pulse. The receiver must pull down the SDA line during the ACK clock pulse so that it
remains stable Low during the High period of this clock pulse. See Figure 33.
A receiver that is addressed is obliged to generate an ACK after each byte is received.
When a slave-receiver doesn't acknowledge the slave address (for example, unable to
receive because it's performing some real-time function), the data line must be left High
by the slave. The master then generates a STOP condition to abort the transfer.
If a slave-receiver acknowledges the slave address, but cannot receive any more data
bytes, the master must abort the transfer. The abort is indicated by the slave generating the
Not Acknowledge (NACK) on the first byte to follow. The slave leaves the data line High
and the master generates the STOP condition.
If a master-receiver is involved in a transfer, it must signal the end of data to the slavetransmitter by not generating an ACK on the final byte that is clocked out of the slave. The
1. ACK is defined as a general Acknowledge bit. By contrast, the I2C Acknowledge bit is represented as AAK, bit 2 of the I2C Control Register, which identifies which ACK signal to transmit.
See Table 84 on page 154.
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slave-transmitter must release the data line to allow the master to generate a STOP or a
repeated START condition.
Data Output
by Transmitter
MSB
Data Output
by Receiver
1
S
SCL Signal
from Master
1
2
8
9
START Condition
Clock Pulse for Acknowledge
Figure 33. I2C Acknowledge
Clock Synchronization
All masters generate their own clocks on the SCL line to transfer messages on the I2C bus.
Data is only valid during the High period of each clock.
Clock synchronization is performed using the wired AND connection of the I2C interfaces
to the SCL line, meaning that a High-to-Low transition on the SCL line causes the relevant
devices to start counting from their Low period. When a device clock goes Low, it holds
the SCL line in that state until the clock High state is reached. See Figure 34. The Low-toHigh transition of this clock, however, may not change the state of the SCL line if another
clock is still within its Low period. The SCL line is held Low by the device with the longest Low period. Devices with shorter Low periods enter a High wait-state during this
time.
When all devices concerned count off their Low period, the clock line is released and goes
High. There is no difference between the device clocks and the state of the SCL line, and
all of the devices start counting their High periods. The first device to complete its High
period again pulls the SCL line Low. In this way, a synchronized SCL clock is generated
with its Low period determined by the device with the longest clock Low period, and its
High period determined by the one with the shortest clock High period.
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Wait
State
Start Counting
High Period
CLK1 Signal
Counter
Reset
CLK2 Signal
SCL Signal
Figure 34. Clock Synchronization In I2C Protocol
Arbitration
A master may start a transfer only if the bus is free. Two or more masters may generate a
START condition within the minimum hold time of the START condition which results in
a defined START condition to the bus. Arbitration takes place on the SDA line, while the
SCL line is at the High level, in such a way that the master which transmits a High level,
while another master is transmitting a Low level switches off its data output stage because
the level on the bus doesn't correspond to its own level.
Arbitration can continue for many bits. Its first stage is comparison of the address bits. If
the masters are each trying to address the same device, arbitration continues with comparison of the data. Because address and data information about the I2C bus is used for arbitration, no information is lost during this process. A master which loses the arbitration can
generate clock pulses until the end of the byte in which it loses the arbitration.
If a master also incorporates a slave function and it loses arbitration during the addressing
stage, it's possible that the winning master is trying to address it. The losing master must
switch over immediately to its slave-receiver mode. Figure 34 illustrates the arbitration
procedure for two masters. Of course, more may be involved (depending on how many
masters are connected to the bus). The moment there is a difference between the internal
data level of the master generating DATA 1 and the actual level on the SDA line, its data
output is switched off, which means that a High output level is then connected to the bus.
As a result, the data transfer initiated by the winning master is not affected. Because control of the I2C bus is decided solely on the address and data sent by competing masters,
there is no central master, nor any order of priority on the bus.
Special attention must be paid if, during a serial transfer, the arbitration procedure is still
in progress at the moment when a repeated START condition or a STOP condition is transmitted to the I2C bus. If it is possible for such a situation to occur, the masters involved
must send this repeated START condition or STOP condition at the same position in the
format frame. In other words, arbitration is not allowed between:
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•
•
•
A repeated START condition and a data bit.
A STOP condition and a data bit.
A repeated START condition and a STOP condition.
Clock Synchronization for Handshake
The Clock synchronizing mechanism can function as a handshake, enabling receivers to
cope with fast data transfers, on either a byte or bit level. The byte level allows a device to
receive a byte of data at a fast rate, but allows the device more time to store the received
byte or to prepare another byte for transmission. Slaves hold the SCL line Low after reception and acknowledge the byte, forcing the master into a wait state until the slave is ready
for the next byte transfer in a handshake procedure.
Operating Modes
Master Transmit
In MASTER TRANSMIT mode, the I2C transmits a number of bytes to a slave receiver.
Enter MASTER TRANSMIT mode by setting the STA bit in the I2C_CTL register to 1.
The I2C then tests the I2C bus and transmits a START condition when the bus is free.
When a START condition is transmitted, the IFLG bit is 1 and the status code in the
I2C_SR register is 08h. Before this interrupt is serviced, the I2C_DR register must be
loaded with either a 7-bit slave address or the first part of a 10-bit slave address, with the
lsb cleared to 0 to specify TRANSMIT mode. The IFLG bit should now be cleared to 0 to
prompt the transfer to continue.
After the 7-bit slave address (or the first part of a 10-bit address) plus the Write bit are
transmitted, the IFLG is set again. A number of status codes are possible in the I2C_SR
register. See Table 75.
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Table 75. I2C Master Transmit Status Codes
Code
I2C State
MCU Response
Next I2C Action
18h
Addr+W transmitted1,
ACK received
For a 7-bit address: write
byte to DATA, clear IFLG
Transmit data byte,
receive ACK
Or set STA, clear IFLG
Transmit repeated
START
Or set STP, clear IFLG
Transmit STOP
Or set STA & STP, clear
IFLG
Transmit STOP then
START
For a 10-bit address: write
extended address byte to
DATA, clear IFLG
Transmit extended
address byte
20h
Addr+W transmitted,
ACK not received
Same as code 18h
Same as code 18h
38h
Arbitration lost
Clear IFLG
Return to idle
Or set STA, clear IFLG
Transmit START when
bus is free
Arbitration lost,
+W received,
ACK transmitted
Clear IFLG, AAK = 02
Receive data byte,
transmit NACK
Or clear IFLG, AAK = 1
Receive data byte,
transmit ACK
78h
Arbitration lost,
General call addr
received, ACK
transmitted
Same as code 68h
Same as code 68h
B0h
Arbitration lost,
SLA+R received,
ACK transmitted
Write byte to DATA, clear
IFLG, clear AAK = 0
Transmit last byte,
receive ACK
68h
Or write byte to DATA, clear Transmit data byte,
IFLG, set AAK = 1
receive ACK
Notes:
1. W is defined as the Write bit; i.e., the lsb is cleared to 0.
2. AAK is defined as the I2C Acknowledge bit.
If 10-bit addressing is being used, then the status code is 18h or 20h after the first part of
a 10-bit address plus the Write bit are successfully transmitted.
After this interrupt is serviced and the second part of the 10-bit address is transmitted, the
I2C_SR register contains one of the codes in Table 76.
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Table 76. I2C 10-Bit Master Transmit Status Codes
Code
2
I C State
MCU Response
2
Next I C Action
38h
Arbitration lost
Clear IFLG
Return to idle
Or set STA, clear IFLG
Transmit START when
bus free
Arbitration lost,
SLA+W received,
ACK transmitted
Clear IFLG, clear AAK = 0
Receive data byte,
transmit NACK
Or clear IFLG, set AAK = 1
Receive data byte,
transmit ACK
Arbitration lost,
SLA+R received,
ACK transmitted
Write byte to DATA,
clear IFLG, clear AAK = 0
Transmit last byte,
receive ACK
Or write byte to DATA,
clear IFLG, set AAK = 1
Transmit data byte,
receive ACK
Second Address byte
+ W transmitted,
ACK received
Write byte to DATA,
clear IFLG
Transmit data byte,
receive ACK
Or set STA, clear IFLG
Transmit repeated
START
Or set STP, clear IFLG
Transmit STOP
Or set STA & STP,
clear IFLG
Transmit STOP then
START
Same as code D0h
Same as code D0h
68h
B0h
D0h
D8h
Second Address byte
+ W transmitted,
ACK not received
If a repeated START condition is transmitted, the status code is 10h instead of 08h.
After each data byte is transmitted, the IFLG is 1 and one of the status codes listed in
Table 77 is in the I2C_SR register.
Table 77. I2C Master Transmit Status Codes For Data Bytes
2
Code I C State
28h
PS013015-0316
MCU Response
Data byte transmitted, Write byte to DATA,
ACK received
clear IFLG
2
Next I C Action
Transmit data byte,
receive ACK
Or set STA, clear IFLG
Transmit repeated START
Or set STP, clear IFLG
Transmit STOP
Or set STA & STP,
clear IFLG
Transmit START then STOP
I2C Serial I/O Interface
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Product Specification
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Table 77. I2C Master Transmit Status Codes For Data Bytes (Continued)
2
Code I C State
MCU Response
2
Next I C Action
30h
Data byte transmitted, Same as code 28h
ACK not received
Same as code 28h
38h
Arbitration lost
Clear IFLG
Return to idle
Or set STA, clear IFLG
Transmit START when bus
free
When all bytes are transmitted, the processor should write a 1 to the STP bit in the
I2C_CTL register. The I2C then transmits a STOP condition, clears the STP bit and returns
to the idle state.
Master Receive
In MASTER RECEIVE mode, the I2C receives a number of bytes from a slave transmitter.
After the START condition is transmitted, the IFLG bit is 1 and the status code 08h is
loaded in the I2C_SR register. The I2C_DR register should be loaded with the slave
address (or the first part of a 10-bit slave address), with the lsb set to 1 to signify a Read.
The IFLG bit should be cleared to 0 as a prompt for the transfer to continue.
When the 7-bit slave address (or the first part of a 10-bit address) and the Read bit are
transmitted, the IFLG bit is set and one of the status codes listed in Table 78 is in the
I2C_SR register.
Table 78. I2C Master Receive Status Codes
Code
40h
2
I C State
Addr + R
transmitted, ACK
received
MCU Response
2
Next I C Action
For a 7-bit address,
clear IFLG, AAK = 0
Receive data byte,
transmit NACK
Or clear IFLG, AAK = 1
Receive data byte,
transmit ACK
For a 10-bit address
Write extended address
byte to DATA, clear IFLG
Transmit extended
address byte
Note: R = Read bit; in essence, the lsb is set to 1.
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Table 78. I2C Master Receive Status Codes (Continued)
Code
48h
2
I C State
MCU Response
Addr + R
For a 7-bit address:
transmitted, ACK not Set STA, clear IFLG
received
Or set STP, clear IFLG
Or set STA & STP,
clear IFLG
2
Next I C Action
Transmit repeated
START
Transmit STOP
Transmit STOP then
START
For a 10-bit address:
Transmit extended
Write extended address byte address byte
to DATA, clear IFLG
38h
Clear IFLG
Return to idle
Or set STA, clear IFLG
Transmit START when
bus is free
Arbitration lost,
SLA+W received,
ACK transmitted
Clear IFLG, clear AAK = 0
Receive data byte,
transmit NACK
Or clear IFLG, set AAK = 1
Receive data byte,
transmit ACK
78h
Arbitration lost,
General call addr
received, ACK
transmitted
Same as code 68h
Same as code 68h
B0h
Arbitration lost,
SLA+R received,
ACK transmitted
Write byte to DATA,
clear IFLG, clear AAK = 0
Transmit last byte,
receive ACK
Or write byte to DATA,
clear IFLG, set AAK = 1
Transmit data byte,
receive ACK
68h
Arbitration lost
Note: R = Read bit; in essence, the lsb is set to 1.
If 10-bit addressing is being used, the slave is first addressed using the full 10-bit address
plus the Write bit. The master then issues a restart followed by the first part of the 10-bit
address again, but with the Read bit. The status code then becomes 40h or 48h. It is the
responsibility of the slave to remember that it had been selected prior to the restart.
If a repeated START condition is received, the status code is 10h instead of 08h.
After each data byte is received, the IFLG is set and one of the status codes listed in
Table 79 is in the I2C_SR register.
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Table 79. I2C Master Receive Status Codes For Data Bytes
Code
50h
2
I C State
MCU Response
Data byte received, Read DATA, clear IFLG,
ACK transmitted
clear AAK = 0
Or read DATA, clear IFLG,
set AAK = 1
58h
38h
Data byte received, Read DATA, set STA,
NACK transmitted clear IFLG
Arbitration lost in
NACK bit
2
Next I C Action
Receive data byte,
transmit NACK
Receive data byte,
transmit ACK
Transmit repeated START
Or read DATA, set STP,
clear IFLG
Transmit STOP
Or read DATA, set
STA & STP, clear IFLG
Transmit STOP then
START
Same as master transmit
Same as master transmit
When all bytes are received, a NACK should be sent, then the processor should write a 1
to the STP bit in the I2C_CTL register. The I2C then transmits a STOP condition, clears
the STP bit and returns to the idle state.
Slave Transmit
In SLAVE TRANSMIT mode, a number of bytes are transmitted to a master receiver.
The I2C enters SLAVE TRANSMIT mode when it receives its own slave address and a
Read bit after a START condition. The I2C then transmits an acknowledge bit (if the AAK
bit is set to 1) and sets the IFLG bit in the I2C_CTL register and the I2C_SR register contains the status code A8h.
Note: When I2C contains a 10-bit slave address (signified by F0h–F7h in the I2C_SAR register), it transmits an acknowledge after the first address byte is received after a restart. An
interrupt is generated, IFLG is set but the status does not change. No second address byte
is sent by the master. It is up to the slave to remember it had been selected prior to the
restart.
I2C goes from MASTER mode to SLAVE TRANSMIT mode when arbitration is lost during the transmission of an address, and the slave address and Read bit are received. This
action is represented by the status code B0h in the I2C_SR register.
The data byte to be transmitted is loaded into the I2C_DR register and the IFLG bit
cleared. After the I2C transmits the byte and receives an acknowledge, the IFLG bit is set
and the I2C_SR register contains B8h. When the final byte to be transmitted is loaded into
the I2C_DR register, the AAK bit is cleared when the IFLG is cleared. After the final byte
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is transmitted, the IFLG is set and the I2C_SR register contains C8h and the I2C returns to
the idle state. The AAK bit must be set to 1 before reentering SLAVE mode.
If no acknowledge is received after transmitting a byte, the IFLG is set and the I2C_SR
register contains C0h. The I2C then returns to the idle state.
If a STOP condition is detected after an acknowledge bit, the I2C returns to the idle state.
Slave Receive
In SLAVE RECEIVE mode, a number of data bytes are received from a master transmitter.
The I2C enters SLAVE RECEIVE mode when it receives its own slave address and a
Write bit (lsb = 0) after a START condition. The I2C transmits an acknowledge bit and sets
the IFLG bit in the I2C_CTL register and the I2C_SR register contains the status code
60h. The I2C also enters SLAVE RECEIVE mode when it receives the general call
address 00h (if the GCE bit in the I2C_SAR register is set). The status code is then 70h.
Note: When the I2C contains a 10-bit slave address (signified by F0h–F7h in the I2C_SAR register), it transmits an acknowledge after the first address byte is received but no interrupt is
generated. IFLG is not set and the status does not change. The I2C generates an interrupt
only after the second address byte is received. The I2C sets the IFLG bit and loads the status code as described above.
I2C goes from MASTER mode to SLAVE RECEIVE mode when arbitration is lost during
the transmission of an address, and the slave address and Write bit (or the general call
address if the CGE bit in the I2C_SAR register is set to 1) are received. The status code in
the I2C_SR register is 68h if the slave address is received or 78h if the general call
address is received. The IFLG bit must be cleared to 0 to allow data transfer to continue.
If the AAK bit in the I2C_CTL register is set to 1 then an acknowledge bit (Low level on
SDA) is transmitted and the IFLG bit is set after each byte is received. The I2C_SR register contains the status code 80h or 90h if SLAVE RECEIVE mode is entered with the
general call address. The received data byte can be read from the I2C_DR register and the
IFLG bit must be cleared to allow the transfer to continue. If a STOP condition or a
repeated START condition is detected after the acknowledge bit, the IFLG bit is set and
the I2C_SR register contains status code A0h.
If the AAK bit is cleared to 0 during a transfer, the I2C transmits a not-acknowledge bit
(High level on SDA) after the next byte is received, and set the IFLG bit. The I2C_SR register contains the status code 88h or 98h if SLAVE RECEIVE mode is entered with the
general call address. The I2C returns to the idle state when the IFLG bit is cleared to 0.
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I2C Registers
Addressing
The processor interface provides access to six 8-bit registers: four Read/Write registers,
one Read-Only register and two Write-Only registers, as indicated in Table 80.
Table 80. I2C Register Descriptions
Register
Description
I2C_SAR
Slave address register
I2C_XSAR
Extended slave address register
I2C_DR
Data byte register
I2C_CTL
Control register
I2C_SR
Status register (Read-Only)
I2C_CCR
Clock Control register (Write-Only)
I2C_SRR
Software reset register (Write-Only)
Resetting the I2C Registers
Hardware reset. When the I2C is reset by a hardware reset of the ZLP12840, the
I2C_SAR, I2C_XSAR, I2C_DR and I2C_CTL registers are cleared to 00h; while the
I2C_SR register is set to F8h.
Software Reset. Perform a software reset by writing any value to the I2C Software Reset
Register (I2C_SRR). A software reset sets the I2C back to idle and the STP, STA, and
IFLG bits of the I2C_CTL register to 0.
I2C Slave Address Register
The I2C_SAR register provides the 7-bit address of the I2C when in SLAVE mode and
allows 10-bit addressing in conjunction with the I2C_XSAR register. I2C_SAR[7:1] =
sla[6:0] is the 7-bit address of the I2C when in 7-bit SLAVE mode. When the I2C receives
this address after a START condition, it enters SLAVE mode. I2C_SAR[7] corresponds to
the first bit received from the I2C bus.
When the register receives an address starting with F7h to F0h (I2C_SAR[7:3] = 11110b),
the I2C recognizes that a 10-bit slave addressing mode is being selected. The I2C sends an
ACK after receiving the I2C_SAR byte (the device does not generate an interrupt at this
point). After the next byte of the address (I2C_XSAR) is received, the I2C generates an
interrupt and goes into SLAVE mode. Then I2C_SAR[2:1] are used as the upper 2 bits for
the 10-bit extended address. The full 10-bit address is supplied by {I2C_SAR[2:1],
I2C_XSAR[7:0]}. See Table 81.
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Table 81. I2C Slave Address Register (I2C_SAR = 00C8h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
Value
Description
[7:1]
SLA
00h–7Fh
7-bit slave address or upper 2 bits,I2C_SAR[2:1],
of address when operating in 10-bit mode.
0
GCE
0
I2C not enabled to recognize the General Call Address.
1
I2C enabled to recognize the General Call Address.
I2C Extended Slave Address Register
The I2C_XSAR register is used in conjunction with the I2C_SAR register to provide 10bit addressing of the I2C when in SLAVE mode. The I2C_SAR value forms the lower 8
bits of the 10-bit slave address. The full 10-bit address is supplied by {I2C_SAR[2:1],
I2C_XSAR[7:0]}.
When the register receives an address starting with F7h to F0h (I2C_SAR[7:3] = 11110b),
the I2C recognizes that a 10-bit slave addressing mode is being selected. The I2C sends an
ACK after receiving the I2C_XSAR byte (the device does not generate an interrupt at this
point). After the next byte of the address (I2C_XSAR) is received, the I2C generates an
interrupt and goes into SLAVE mode. Then I2C_SAR[2:1] are used as the upper 2 bits for
the 10-bit extended address. The full 10-bit address is supplied by {I2C_SAR[2:1],
I2C_XSAR[7:0]}. See Table 82.
Table 82. I2C Extended Slave Address Register (I2C_XSAR = 00C9h)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
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Bit
Position
[7:0]
SLAX
Value
Description
00h–FFh Least significant 8 bits of the 10-bit extended slave address.
I2C Data Register
This register contains the data byte/slave address to be transmitted or the data byte just
received. In transmit mode, the most significant bit of the byte is transmitted first. In
receive mode, the first bit received is placed in the most significant bit of the register.
After each byte is transmitted, the I2C_DR register contains the byte that is present on the
bus in case a lost arbitration event occurs. See Table 83.
Table 83. I2C Data Register (I2C_DR = 00CAh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CPU Access
Note: R/W = Read/Write.
Bit
Position
[7:0]
DATA
Value
00h–FFh
Description
I2C data byte.
I2C Control Register
The I2C_CTL register is a control register that is used to control the interrupts and the
master slave relationships on the I2C bus.
When the Interrupt Enable bit (IEN) is set to 1, the interrupt line goes High when the IFLG
is set to 1. When IEN is cleared to 0, the interrupt line always remains Low.
When the Bus Enable bit (ENAB) is set to 0, the I2C bus inputs SCLx and SDAx are
ignored and the I2C module does not respond to any address on the bus. When ENAB is
set to 1, the I2C responds to calls to its slave address and to the general call address if the
GCE bit (I2C_SAR[0]) is set to 1.
When the Master Mode Start bit (STA) is set to 1, the I2C enters MASTER mode and
sends a START condition on the bus when the bus is free. If the STA bit is set to 1 when
the I2C module is already in MASTER mode and one or more bytes are transmitted, then a
repeated START condition is sent. If the STA bit is set to 1 when the I2C block is being
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accessed in SLAVE mode, the I2C completes the data transfer in SLAVE mode and then
enters MASTER mode when the bus is released. The STA bit is automatically cleared after
a START condition is set. Writing a 0 to this bit produces no effect.
If the Master Mode Stop bit (STP) is set to 1 in MASTER mode, a STOP condition is
transmitted on the I2C bus. If the STP bit is set to 1 in slave move, the I2C module operates
as if a STOP condition is received, but no STOP condition is transmitted. If both STA and
STP bits are set, the I2C block first transmits the STOP condition (if in MASTER mode)
and then transmit the START condition. The STP bit is cleared automatically. Writing a 0
to this bit produces no effect.
The I2C Interrupt Flag (IFLG) is set to 1 automatically when any of 30 of the possible 31
I2C states is entered. The only state that does not set the IFLG bit is state F8h. If IFLG is
set to 1 and the IEN bit is also set, an interrupt is generated. When IFLG is set by the I2C,
the Low period of the I2C bus clock line is stretched and the data transfer is suspended.
When a 0 is written to IFLG, the interrupt is cleared and the I2C clock line is released.
When the I2C Acknowledge bit (AAK) is set to 1, an Acknowledge is sent during the
acknowledge clock pulse on the I2C bus if:
•
Either the whole of a 7-bit slave address or the first or second byte of a 10-bit slave address is received
•
The general call address is received and the General Call Enable bit in I2C_SAR is set
to 1
•
A data byte is received while in MASTER or SLAVE modes
When AAK is cleared to 0, a NACK is sent when a data byte is received in MASTER or
SLAVE mode. If AAK is cleared to 0 in the Slave Transmitter mode, the byte in the
I2C_DR register is assumed to be the final byte. After this byte is transmitted, the I2C
block enter states C8h, then returns to the idle state. The I2C module does not respond to
its slave address unless AAK is set. See Table 84.
Table 84. I2C Control Registers (I2C_CTL = 00CBh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R
R
CPU Access
Note: R/W = Read/Write; R = Read Only.
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155
Bit
Position
Value
Description
7
IEN
0
I2C interrupt is disabled.
1
I2C interrupt is enabled.
6
ENAB
0
The I2C bus (SCL/SDA) is disabled and all inputs are
ignored.
1
The I2C bus (SCL/SDA) is enabled.
5
STA
0
Master mode START condition is sent.
1
Master mode start-transmit START condition on the bus.
4
STP
0
Master mode STOP condition is sent.
1
Master mode stop-transmit STOP condition on the bus.
3
IFLG
0
I2C interrupt flag is not set.
1
I2C interrupt flag is set.
2
AAK
0
Not Acknowledge.
1
Acknowledge.
[1:0]
00
Reserved.
I2C Status Register
The I2C_SR register is a Read-Only register that contains a 5-bit status code in the five
most significant bits: the three least significant bits are always 0. The Read-Only I2C_SR
registers share the same I/O addresses as the Write-Only I2C_CCR registers. See Table 85.
Table 85. I2C Status Registers (I2C_SR = 00CCh)
Bit
7
6
5
4
3
2
1
0
Reset
1
1
1
1
1
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read only.
Bit
Position
[7:3]
STAT
[2:0]
PS013015-0316
Value
00000–11111
000
Description
5-bit I2C status code.
Reserved.
I2C Serial I/O Interface
eZ80L92 MCU
Product Specification
156
There are 29 possible status codes, as listed in Table 86. When the I2C_SR register contains the status code F8h, no relevant status information is available, no interrupt is generated and the IFLG bit in the I2C_CTL register is not set. All other status codes correspond
to a defined state of the I2C.
When each of these states is entered, the corresponding status code appears in this register
and the IFLG bit in the I2C_CTL register is set. When the IFLG bit is cleared, the status
code returns to F8h.
Table 86. I2C Status Codes
PS013015-0316
Code
Status
00h
Bus error
08h
START condition transmitted
10h
Repeated START condition transmitted
18h
Address and Write bit transmitted, ACK received
20h
Address and Write bit transmitted, ACK not received
28h
Data byte transmitted in MASTER mode, ACK received
30h
Data byte transmitted in MASTER mode, ACK not received
38h
Arbitration lost in address or data byte
40h
Address and Read bit transmitted, ACK received
48h
Address and Read bit transmitted, ACK not received
50h
Data byte received in MASTER mode, ACK transmitted
58h
Data byte received in MASTER mode, NACK transmitted
60h
Slave address and Write bit received, ACK transmitted
68h
Arbitration lost in address as master, slave address and Write bit received,
ACK transmitted
70h
General Call address received, ACK transmitted
78h
Arbitration lost in address as master, General Call address received, ACK
transmitted
80h
Data byte received after slave address received, ACK transmitted
88h
Data byte received after slave address received, NACK transmitted
90h
Data byte received after General Call received, ACK transmitted
98h
Data byte received after General Call received, NACK transmitted
A0h
STOP or repeated START condition received in SLAVE mode
A8h
Slave address and Read bit received, ACK transmitted
I2C Serial I/O Interface
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Product Specification
157
Table 86. I2C Status Codes (Continued)
Code
Status
B0h
Arbitration lost in address as master, slave address and Read bit received,
ACK transmitted
B8h
Data byte transmitted in SLAVE mode, ACK received
C0h
Data byte transmitted in SLAVE mode, ACK not received
C8h
Last byte transmitted in SLAVE mode, ACK received
D0h
Second Address byte and Write bit transmitted, ACK received
D8h
Second Address byte and Write bit transmitted, ACK not received
F8h
No relevant status information, IFLG = 0
If an illegal condition occurs on the I2C bus, the bus error state is entered (status code
00h). To recover from this state, the STP bit in the I2C_CTL register must be set and the
IFLG bit cleared. The I2C then returns to the idle state. No STOP condition is transmitted
on the I2C bus.
Note:
The STP and STA bits may be set to 1 at the same time to recover from the bus error. The
I2C then sends a START.
I2C Clock Control Register
The I2C_CCR register is a Write-Only register. The seven LSBs control the frequency at
which the I2C bus is sampled and the frequency of the I2C clock line (SCL) when the I2C
is in MASTER mode. The Write-Only I2C_CCR registers share the same I/O addresses as
the Read-Only I2C_SR registers. See Table 87.
Table 87. I2C Clock Control Registers (I2C_CCR = 00CCh)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Read only.
Bit
Position
7
PS013015-0316
Value
0
Description
Reserved.
I2C Serial I/O Interface
eZ80L92 MCU
Product Specification
158
Bit
Position
Value
[6:3]
M
0000–1111
[2:0]
N
000–111
Description
I2C clock divider scalar value.
I2C clock divider exponent.
The I2C clocks are derived from the ZLP12840’s system clock. The frequency of the
ZLP12840 system clock is fSCK. The I2C bus is sampled by the I2C block at the frequency
fSAMP supplied by:
fSAMP
=
fSCLK
2N
In MASTER mode, the I2C clock output frequency on SCL (fSCL) is supplied by:
fSCL =
fSCLK
10 • (M + 1)(2)N
The use of two separately-programmable dividers allows the MASTER mode output frequency to be set independently of the frequency at which the I2C bus is sampled. This feature is particularly useful in multimaster systems because the frequency at which the I2C
bus is sampled must be at least 10 times the frequency of the fastest master on the bus to
ensure that START and STOP conditions are always detected. By using two programmable clock divider stages, a high sampling frequency can be ensured while allowing the
MASTER mode output to be set to a lower frequency.
Bus Clock Speed
The I2C bus is defined for bus clock speeds up to 100 Kbps (400 Kbps in FAST mode).
To ensure correct detection of START and STOP conditions on the bus, the I2C must sample the I2C bus at least ten times faster than the bus clock speed of the fastest master on the
bus. The sampling frequency should therefore be at least 1 MHz (4 MHz in FAST mode)
to guarantee correct operation with other bus masters.
The I2C sampling frequency is determined by the frequency of the ZLP12840 system
clock and the value in the I2C_CCR bits 2 to 0. The bus clock speed generated by the I2C
in MASTER mode is determined by the frequency of the input clock and the values in
I2C_CCR[2:0] and I2C_CCR[6:3].
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I2C Software Reset Register
The I2C_SRR register is a Write-Only register. Writing any value to this register performs
a software reset of the I2C module. See Table 88.
Table 88. I2C Software Reset Register (I2C_SRR = 00CDh)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write-Only.
Bit
Position
[7:0]
SRR
PS013015-0316
Value
00h–FFh
Description
Writing any value to this register performs a software
reset of the I2C module.
I2C Serial I/O Interface
eZ80L92 MCU
Product Specification
160
Zilog Debug Interface
The Zilog Debug Interface (ZDI) provides a built-in debugging interface to the eZ80 CPU.
ZDI provides basic in-circuit emulation features including:
•
•
•
•
•
•
•
•
•
Examining and modifying internal registers.
Examining and modifying memory.
Starting and stopping the user program.
Setting program and data break points.
Single-stepping the user program.
Executing user-supplied instructions.
Debugging the final product with the inclusion of one small connector.
Downloading code into SRAM.
‘C’ source-level debugging using Zilog Developer Studio (ZDS II)
The above features are built into the silicon. Control is provided through a two-wire interface that is connected to the ZPAK II emulator. Figure 35 illustrates a typical setup using a
target board, ZPAK II, and the host PC running ZDS II. For more information on ZPAK II
and ZDS II, refer to www.zilog.com.
Target Board
ZiLOG
Developer
Studio
ZPAK
Emulator
C
O
N
N
E
C
T
O
R
eZ80
Product
Figure 35. Typical ZDI Debug Setup
ZDI allows reading and writing of most internal registers without disturbing the state of
the machine. Reads and Writes to memory may occur as fast as the ZDI can download and
upload data, with a maximum frequency of one-half the ZLP12840 system clock fre-
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quency. Table 89 lists the recommended frequencies of the ZDI clock in relation to the
system clock.
Table 89. Recommended ZDI Clock versus System Clock Frequency
System Clock
Frequency
ZDI Clock
Frequency
3–10 MHz
1 MHz
8–16 MHz
2 MHz
12–24 MHz
4 MHz
20–50 MHz
8 MHz
ZDI-Supported Protocol
ZDI supports a bidirectional serial protocol. The protocol defines any device that sends
data as the transmitter and any receiving device as the receiver. The device controlling the
transfer is the master and the device being controlled is the slave. The master always
initiates the data transfers and provides the clock for both receive and transmit operations.
The ZDI block on the ZLP12840 MCU is considered as slave in all data transfers.
Figure 36 illustrates the schematic for building a connector on a target board. This
connector allows you to connect directly to the ZPAK emulator using a six-pin header.
TVDD
(Target VDD )
10 K‰
eZ80L92
MCU
10 K‰
TCK (ZCL)
TDI (ZDA)
2
1
4
3
6
5
6-Pin Target Connector
Figure 36. Schematic For Building a Target Board ZPAK Connector
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ZDI Clock and Data Conventions
The two pins used for communication with the ZDI block are ZDI Clock pin (ZCL) and
ZDI Data pin (ZDA). On ZLP12840 MCU, the ZCL pin is shared with the TCK pin while
the ZDA pin is shared with the TDI pin. The ZCL pin and ZDA pin functions are only
available when the on-chip instrumentation is disabled and the ZDI is therefore enabled.
For general data communication, the data value on the ZDA pin changes only when ZCL
is Low (0). The only exception is the ZDI START bit, which is indicated by a High-toLow transition (falling edge) on the ZDA pin while ZCL is High.
Data is shifted in and out of ZDI, with the most significant bit (bit 7) of each byte being
first in time, and the least significant bit (bit 0) last in time. The information is transferred
between the master and the slave in 8-bit (single-byte) units. Each byte is transferred with
nine clock cycles: eight to shift the data, and the ninth for internal operations.
ZDI START Condition
All the ZDI commands are preceded by a ZDI START signal, which is a High-to-Low
transition of ZDA when ZCL is High. The ZDI slave on the ZLP12840 continually monitors the ZDA and ZCL lines for the START signal and does not respond to any command
until this condition is met. The master pulls ZDA Low, with ZCL High, to indicate the
beginning of a data transfer with the ZDI block. Figure 37 and Figure 38 illustrate a valid
ZDI START signal prior to writing and reading the data, respectively. A Low-to-High
transition of ZDA while the ZCL is High produces no effect.
Data is shifted in during a Write to the ZDI block on the rising edge of ZCL, as illustrated
in Figure 37. Data is shifted out during a Read from the ZDI block on the falling edge of
ZCL as illustrated in Figure 38. When an operation is completed, the master stops during
the ninth cycle and holds the ZCL signal High.
ZDI Data In
(Write)
ZDI Data In
(Write)
ZCL
ZDA
Start Signal
Figure 37. ZDI Write Timing
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ZDI Data Out
(Read)
ZDI Data Out
(Read)
ZCL
ZDA
Start Signal
Figure 38. ZDI Read Timing
ZDI Single-Bit Byte Separator
Following each 8-bit ZDI data transfer, a single-bit byte separator is used. To initiate a
new ZDI command, the single-bit byte separator must be High (logical 1) to allow a new
ZDI START command to be sent. For all other cases, the single-bit byte separator is either
Low (logical 0) or High (logical 1). When ZDI is configured to allow the CPU to accept
external bus requests, the single-bit byte separator must be Low (logical 0) during all ZDI
commands. This Low value indicates that ZDI is still operating and is not ready to
relinquish the Bus. The CPU does not accept the external bus requests until the single-bit
byte separator is a High (logical 1). For more information on accepting bus requests in
ZDI DEBUG mode, see Bus Requests During ZDI Debug Mode on page 167.
ZDI Register Addressing
Following a START signal, the ZDI master must output the ZDI register address. All data
transfers with the ZDI block use special ZDI registers. The ZDI control registers that
reside in the ZDI register address space should not be confused with the ZLP12840
peripheral registers that reside in the I/O address space.
Many locations in the ZDI control register address space are shared by two registers, one
for Read-Only access and another one for Write-Only access. For example, a Read from
ZDI register address 00h returns the eZ80 Product ID Low Byte while a Write to this same
location, 00h, stores the Low byte of one of the address match values used for generating
break points.
The format for a ZDI address is seven bits of address, followed by one bit for Read or
Write control, and completed by a single-bit byte separator. The ZDI executes a Read or
Write operation depending on the state of the R/W bit (0 = Write, 1 = Read). If no new
START command is issued at completion of the Read or Write operation, the operation
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can be repeated. This allows repeated Read or Write operations without having to resend
the ZDI command. A START signal must follow to initiate a new ZDI command.
Figure 39 illustrates the timing for address Writes to ZDI registers.
Single-Bit
Byte Separator
or new ZDI
START Signal
ZDI Address Byte
ZCL
S
ZDA
1
2
3
4
5
6
7
8
A6
A5
A4
A3
A2
A1
A0
R/W
msb
9
0/1
lsb
0 = WRITE
1 = READ
START
Signal
Figure 39. ZDI Address Write Timing
ZDI Write Operations
ZDI Single-Byte Write
For single-byte Write operations, the address and write control bit are first written to the
ZDI block. Following the single-bit byte separator, the data is shifted into the ZDI block
on the next 8 rising edges of ZCL. The master terminates activity after 8 clock cycles.
Figure 40 illustrates the timing for ZDI single-byte Write operations.
ZDI Data Byte
ZCL
7
8
9
1
2
3
4
5
6
7
8
ZDA
A0
Write
0/1
D7
D6
D5
D4
D3
D2
D1
D0
msb
of DATA
lsb of
ZDI Address
Single-Bit
Byte Separator
9
1
lsb
of DATA
End of Data
or New ZDI
START Signal
Figure 40. ZDI Single-Byte Data Write Timing
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Product Specification
165
ZDI Block Write
The Block Write operation is initiated in the same manner as the single-byte Write operation, but instead of terminating the Write operation after the first data byte is transferred,
the ZDI master can continue to transmit additional bytes of data to the ZDI slave on the
ZLP12840. After the receipt of each byte of data the ZDI register address increments by 1.
If the ZDI register address reaches the end of the Write-Only ZDI register address space
(30h), the address stops incrementing. Figure 41 illustrates the timing for ZDI Block
Write operations.
ZDI Data Bytes
ZCL
7
8
9
1
2
3
7
8
9
1
2
ZDA
A0
Write
0/1
D7
D6
D5
D1
D0
0/1
D7
D6
msb
of DATA
Byte 1
lsb of
ZDI Address
Single-Bit
Byte Separator
lsb
of DATA
Byte 1
9
1
msb
of DATA
Byte 2
Single-Bit
Byte Separator
Figure 41. ZDI Block Data Write Timing
ZDI Read Operations
ZDI Single-Byte Read
Single-byte Read operations are initiated in the same manner as single-byte Write operations, with the exception that the R/W bit of the ZDI register address is set to 1. Upon
receipt of a slave address with the R/W bit set to 1, the ZLP12840’s ZDI block loads the
selected data into the shifter at the beginning of the first cycle following the single-bit data
separator. The most significant bit (msb) is shifted out first. Figure 42 illustrates the timing
for ZDI single-byte Read operations.
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166
ZDI Data Byte
ZCL
7
8
9
1
2
3
4
5
6
7
8
ZDA
A0
Read
0/1
D7
D6
D5
D4
D3
D2
D1
D0
msb
of DATA
1
lsb
of DATA
Single-Bit
Byte Separator
lsb of
ZDI Address
9
End of Data
or New ZDI
START Signal
Figure 42. ZDI Single-Byte Data Read Timing
ZDI Block Read
A Block Read operation is initiated the same as a single-byte Read; however, the ZDI
master continues to clock in the next byte from the ZDI slave as the ZDI slave continues to
output data. The ZDI register address counter increments with each Read. If the ZDI
register address reaches the end of the Read-Only ZDI register address space (20h), the
address stops incrementing. Figure 43 illustrates the ZDI’s Block Read timing.
ZDI Data Bytes
ZCL
7
8
9
1
2
3
7
8
9
1
2
ZDA
A0
Read
0/1
D7
D6
D5
D1
D0
0/1
D7
D6
msb
of DATA
Byte 1
lsb of
ZDI Address
Single-Bit
Byte Separator
lsb
of DATA
Byte 1
9
1
msb
of DATA
Byte 2
Single-Bit
Byte Separator
Figure 43. ZDI Block Data Read Timing
Operation of the ZLP12840 During ZDI Break Points
If the ZDI forces the CPU to break, only the CPU suspends operation. The system clock
continues to operate and drive other peripherals. Those peripherals that can operate autonomously from the CPU may continue to operate, if so enabled. For example, the Watchdog
Timer and Programmable Reload Timers continue to count during a ZDI break point.
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When using the ZDI interface, any Write or Read operations of peripheral registers in the
I/O address space produces the same effect as Read or Write operations using the CPU.
Because many register Read/Write operations exhibit secondary effects, such as clearing
flags or causing operations to commence, the effects of the Read/Write operations during a
ZDI Break must be taken into consideration.
Bus Requests During ZDI Debug Mode
The ZDI block on the ZLP12840 allows an external device to take control of the address
and data bus while the ZLP12840 is in DEBUG mode. ZDI_BUSACK_EN causes ZDI to
allow or prevent acknowledgement of bus requests by external peripherals. The bus
acknowledge only occurs at the end of the current ZDI operation (indicated by a High during the single-bit byte separator). The default reset condition is for bus acknowledgement
to be disabled. To allow bus acknowledgement, the ZDI_BUSACK_EN must be written.
When an external bus request (BUSREQ pin asserted) is detected, ZDI waits until completion of the current operation before responding. ZDI acknowledges the bus request by
asserting the bus acknowledge (BUSACK) signal. If the ZDI block is not currently shifting data, it acknowledges the bus request immediately. ZDI uses the single-bit byte separator of each data word to determine if it is at the end of a ZDI operation. If the bit is a
logical 0, ZDI does not assert BUSACK to allow additional data Read or Write operations.
If the bit is a logical 1, indicating completion of the ZDI commands, BUSACK is asserted.
Potential Hazards of Enabling Bus Requests During Debug Mode
There are some potential hazards that the user must be aware of when enabling external
bus requests during ZDI Debug mode. First, when the address and data bus are being used
by an external source, ZDI must only access ZDI registers and internal CPU registers to
prevent possible Bus contention. The bus acknowledge status is reported in the
ZDI_BUS_STAT register. The BUSACK output pin also indicates the bus acknowledge
state.
A second hazard is that when a bus acknowledge is granted, the ZDI is subject to any
WAIT states that are assigned to the device currently being accessed by the external
peripheral. To prevent data errors, ZDI should avoid data transmission while another
device is controlling the bus.
Finally, exiting ZDI Debug mode while an external peripheral controls the address and
data buses, as indicated by BUSACK assertion, may produce unpredictable results.
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ZDI Write-Only Registers
Table 90 lists the ZDI Write-Only registers. Many of the ZDI Write-Only addresses are
shared with ZDI Read-Only registers.
Table 90. ZDI Write-Only Registers
Reset
Value
ZDI Address
ZDI Register Name
ZDI Register Function
00h
ZDI_ADDR0_L
Address Match 0 Low Byte
XXh
01h
ZDI_ADDR0_H
Address Match 0 High Byte
XXh
02h
ZDI_ADDR0_U
Address Match 0 Upper Byte
XXh
04h
ZDI_ADDR1_L
Address Match 1 Low Byte
XXh
05h
ZDI_ADDR1_H
Address Match 1 High Byte
XXh
06h
ZDI_ADDR1_U
Address Match 1 Upper Byte
XXh
08h
ZDI_ADDR2_L
Address Match 2 Low Byte
XXh
09h
ZDI_ADDR2_H
Address Match 2 High Byte
XXh
0Ah
ZDI_ADDR2_U
Address Match 2 Upper Byte
XXh
0Ch
ZDI_ADDR3_L
Address Match 3 Low Byte
XXh
0Dh
ZDI_ADDR3_H
Address Match 3 High Byte
XXh
0Eh
ZDI_ADDR3_U
Address Match 4 Upper Byte
XXh
10h
ZDI_BRK_CTL
Break Control register
00h
11h
ZDI_MASTER_CTL
Master Control register
00h
13h
ZDI_WR_DATA_L
Write Data Low Byte
XXh
14h
ZDI_WR_DATA_H
Write Data High Byte
XXh
15h
ZDI_WR_DATA_U
Write Data Upper Byte
XXh
16h
ZDI_RW_CTL
Read/Write Control register
00h
17h
ZDI_BUS_CTL
Bus Control register
00h
21h
ZDI_IS4
Instruction Store 4
XXh
22h
ZDI_IS3
Instruction Store 3
XXh
23h
ZDI_IS2
Instruction Store 2
XXh
24h
ZDI_IS1
Instruction Store 1
XXh
25h
ZDI_IS0
Instruction Store 0
XXh
30h
ZDI_WR_MEM
Write Memory register
XXh
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Product Specification
169
ZDI Read-Only Registers
Table 91 lists the ZDI Read-Only registers. Many of the ZDI Read-Only addresses are
shared with ZDI Write-Only registers.
Table 91. ZDI Read-Only Registers
Reset
Value
ZDI Address
ZDI Register Name
ZDI Register Function
00h
ZDI_ID_L
eZ80 Product ID Low Byte register
06h
01h
ZDI_ID_H
eZ80 Product ID High Byte register
00h
02h
ZDI_ID_REV
eZ80 Product ID Revision register
XXh
03h
ZDI_STAT
Status register
00h
10h
ZDI_RD_L
Read Memory Address Low Byte register
XXh
11h
ZDI_RD_H
Read Memory Address High Byte register
XXh
12h
ZDI_RD_U
Read Memory Address Upper Byte register
XXh
17h
ZDI_BUS_STAT
Bus Status register
00h
20h
ZDI_RD_MEM
Read Memory Data Value
XXh
ZDI Register Definitions
ZDI Address Match Registers
The four sets of address match registers are used for setting the addresses for generating
break points. When the accompanying BRK_ADDRx bit is set in the ZDI Break Control
register to enable the particular address match, the current ZLP12840 address is compared
with the 3-byte address set, {ZDI_ADDRx_U, ZDI_ADDRx_H, ZDI_ADDR_x_L}. If
the CPU is operating in ADL mode, the address is supplied by ADDR[23:0]. If the CPU is
operating in Z80 mode, the address is supplied by {MBASE[7:0], ADDR[15:0]}. If a
match is found, ZDI issues a BREAK to the ZLP12840 placing the processor in ZDI mode
pending further instructions from the ZDI interface block. If the address is not the first opcode fetch, the ZDI BREAK is executed at the end of the instruction in which it is executed. There are four sets of address match registers. They can be used in conjunction with
each other to break on branching instructions. See Table 92.
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Table 92. ZDI Address Match Registers ZDI_ADDR0_L = 00h, ZDI_ADDR0_H
= 01h, ZDI_ADDR0_U = 02h, ZDI_ADDR1_L = 04h, ZDI_ADDR1_H = 05h,
ZDI_ADDR1_U = 06h, ZDI_ADDR2_L = 08h, ZDI_ADDR2_H = 09h,
ZDI_ADDR2_U = 0Ah, ZDI_ADDR3_L = 0Ch, ZDI_ADDR3_H = 0Dh, and
ZDI_ADDR3_U = 0Eh in the ZDI Register Write-Only Address Space
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write-only.
Bit
Position
[7:0]
ZDI_ADDRx_L,
ZDI_ADDRx_H,
or
ZDI_ADDRx_U
Value
Description
00h–FFh The four sets of ZDI address match registers are used
for setting the addresses for generating break points.
The 24-bit addresses are supplied by {ZDI_ADDRx_U,
ZDI_ADDRx_H, ZDI_ADDRx_L, where x is 0, 1, 2, or 3.
ZDI Break Control Register
The ZDI Break Control register is used to enable break points. ZDI asserts a BREAK
when the CPU instruction address, ADDR[23:0], matches the value in the ZDI Address
Match 3 registers, {ZDI_ADDR3_U, ZDI_ADDR3_H, ZDI_ADDR3_L}. Breaks only
occur on an instruction boundary. If the instruction address is not the beginning of an
instruction (that is, for multibyte instructions), then the BREAK occurs at the end of the
current instruction. The BRK_NEXT bit is set to 1. The BRK_NEXT bit must be reset to 0
to release the BREAK. See Table 93.
Table 93. ZDI Break Control Register (ZDI_BRK_CTL = 10h in the ZDI WriteOnly Register Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write-only.
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171
Bit
Position
7
BRK_NEXT
6
brk_addr3
5
brk_addr2
4
brk_addr1
3
brk_addr0
2
ign_low_1
PS013015-0316
Value Description
0
The ZDI BREAK on the next CPU instruction is disabled.
Clearing this bit releases the CPU from its current BREAK
condition.
1
The ZDI BREAK on the next CPU instruction is enabled.
The CPU can use multibyte Op Codes and multibyte
operands. break points only occur on the first Op Code in a
multibyte Op Code instruction. If the ZCL pin is High and
the ZDA pin is Low at the end of RESET, this bit is set to 1
and a BREAK occurs on the first instruction following the
RESET. This bit is set automatically during ZDI BREAK on
address match. A BREAK can also be forced by writing a 1
to this bit.
0
The ZDI BREAK, upon matching break address 3,
is disabled.
1
The ZDI BREAK, upon matching break address 3,
is enabled.
0
The ZDI BREAK, upon matching break address 2,
is disabled.
1
The ZDI BREAK, upon matching break address 2,
is enabled.
0
The ZDI BREAK, upon matching break address 1,
is disabled.
1
The ZDI BREAK, upon matching break address 1,
is enabled.
0
The ZDI BREAK, upon matching break address 0,
is disabled.
1
The ZDI BREAK, upon matching break address 0,
is enabled.
0
The Ignore the Low Byte function of the ZDI Address Match
1 registers is disabled. If BRK_ADDR1 is set to 1, ZDI
initiates a BREAK when the entire 24-bit address,
ADDR[23:0], matches the 3-byte value {ZDI_ADDR1_U,
ZDI_ADDR1_H, ZDI_ADDR1_L}.
1
The Ignore the Low Byte function of the ZDI Address Match
1 registers is enabled. If BRK_ADDR1 is set to 1, ZDI
initiates a BREAK when only the upper 2 bytes of the 24-bit
address, ADDR[23:8], match the 2-byte value
{ZDI_ADDR1_U, ZDI_ADDR1_H}. As a result, a BREAK
can occur anywhere within a 256-byte page.
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172
Bit
Position
1
ign_low_0
0
single_step
Value Description
0
The Ignore the Low Byte function of the ZDI Address Match
1 registers is disabled. If BRK_ADDR0 is set to 1, ZDI
initiates a BREAK when the entire 24-bit address,
ADDR[23:0], matches the 3-byte value {ZDI_ADDR0_U,
ZDI_ADDR0_H, ZDI_ADDR0_L}.
1
The Ignore the Low Byte function of the ZDI Address Match
1 registers is enabled. If the BRK_ADDR1 is set to 0, ZDI
initiates a BREAK when only the upper 2 bytes of the 24-bit
address, ADDR[23:8], match the 2 bytes value
{ZDI_ADDR0_U, ZDI_ADDR0_H}. As a result, a BREAK
can occur anywhere within a 256-byte page.
0
ZDI SINGLE STEP mode is disabled.
1
ZDI SINGLE STEP mode is enabled. ZDI asserts a BREAK
following execution of each instruction.
ZDI Master Control Register
The ZDI Master Control register provides control of the ZLP12840. It is capable of forcing a RESET and waking up the ZLP12840 from the low-power modes (HALT or
SLEEP). See Table 94.
Table 94. ZDI Master Control Register (ZDI_MASTER_CTL = 11h in ZDI
Register Write Address Spaces)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write-only.
Bit
Position
7
ZDI_RESET
[6:0]
PS013015-0316
Value
Description
0
No action.
1
Initiate a RESET of the ZLP12840. This bit is
automatically cleared at the end of the RESET event.
0000000 Reserved.
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ZDI Write Data Registers
These three registers are used in the ZDI Write-Only register address space to store the
data that is written when a Write instruction is sent to the ZDI Read/Write Control register
(ZDI_RW_CTL). The ZDI Read/Write Control register is located at ZDI address 16h
immediately following the ZDI Write Data registers. As a result, the ZDI Master is
allowed to write the data to {ZDI_WR_U, ZDI_WR_H, ZDI_WR_L} and the Write command in one data transfer operation. See Table 95.
Table 95. ZDI Write Data Registers (ZDI_WR_U = 13h, ZDI_WR_H = 14h, and
ZDI_WR_L = 15h in the ZDI Register Write-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: X = Undefined; W = Write.
Bit
Position
[7:0]
ZDI_WR_L,
ZDI_WR_H,
or
ZDI_WR_L
Value
Description
00h–FFh These registers contain the data that is written during
execution of a Write operation defined by the
ZDI_RW_CTL register. The 24-bit data value is stored
as {ZDI_WR_U, ZDI_WR_H, ZDI_WR_L}. If less than
24 bits of data are required to complete the required
operation, the data is taken from the least significant
byte(s).
ZDI Read/Write Control Register
The ZDI Read/Write Control register is used in the ZDI Write-Only Register address to
read data from, write data to, and manipulate the CPU’s registers or memory locations.
When this register is written, the ZLP12840 immediately performs the operation corresponding to the data value written as described in Table 96.
When a Read operation is executed via this register, the requested data values are placed in
the ZDI Read Data registers {ZDI_RD_U, ZDI_RD_H, ZDI_RD_L}. When a Write operation is executed via this register, the Write data is taken from the ZDI Write Data registers
{ZDI_WR_U, ZDI_WR_H, ZDI_WR_L}. See Table 96. For more information on the
CPU registers, refer to the eZ80® CPU User Manual (UM0077).
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Table 96. ZDI Read/Write Control Register Functions (ZDI_RW_CTL = 16h in
the ZDI Register Write-Only Address Space)
Hex
Value
Command
Hex
Value
Command
00
Read {MBASE, A, F}
ZDI_RD_U ← MBASE
ZDI_RD_H ← F
ZDI_RD_L ← A
80
Write {MBASE, A, F}
MBASE ← ZDI_WR_U
F ← ZDI_WR_H
A ← ZDI_WR_L
01
Read BC
ZDI_RD_U ← BCU
ZDI_RD_H ← B
ZDI_RD_L ← C
81
Write BC
BCU ← ZDI_WR_U
B ← ZDI_WR_H
C ← ZDI_WR_L
02
Read DE
ZDI_RD_U ← DEU
ZDI_RD_H ← D
ZDI_RD_L ← E
82
Write DE
DEU ← ZDI_WR_U
D ← ZDI_WR_H
E ← ZDI_WR_L
03
Read HL
ZDI_RD_U ← HLU
ZDI_RD_H ← H
ZDI_RD_L ← L
83
Write HL
HLU ← ZDI_WR_U
H ← ZDI_WR_H
L ← ZDI_WR_L
04
Read IX
ZDI_RD_U ← IXU
ZDI_RD_H ← IXH
ZDI_RD_L ← IXL
84
Write IX
IXU ← ZDI_WR_U
IXH ← ZDI_WR_H
IXL ← ZDI_WR_L
05
Read IY
ZDI_RD_U ← IYU
ZDI_RD_H ← IYH
ZDI_RD_L ← IYL
85
Write IY
IYU ← ZDI_WR_U
IYH ← ZDI_WR_H
IYL ← ZDI_WR_L
06
Read SP
In ADL mode, SP = SPL.
In Z80 mode, SP = SPS.
86
Write SP
In ADL mode, SP = SPL.
In Z80 mode, SP = SPS.
07
Read PC
ZDI_RD_U ← PC[23:16]
ZDI_RD_H ← PC[15:8]
ZDI_RD_L ← PC[7:0]
87
Write PC
PC[23:16] ← ZDI_WR_U
PC[15:8] ← ZDI_WR_H
PC[7:0] ← ZDI_WR_L
08
Set ADL
ADL ← 1
88
Reserved
Note: The eZ80 CPU’s alternate register set (A’, F’, B’, C’, D’, E’, HL’) cannot be read directly.
The ZDI programmer must execute the exchange instruction (EXX) to gain access to the
alternate eZ80 CPU register set.
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Product Specification
175
Table 96. ZDI Read/Write Control Register Functions (ZDI_RW_CTL = 16h in
the ZDI Register Write-Only Address Space) (Continued)
Hex
Value
Command
Hex
Value
Command
09
Reset ADL
ADL ← 0
89
Reserved
0A
Exchange CPU register sets
AF ← AF’
BC ← BC’
DE ← DE’
HL ← HL’
8A
Reserved
0B
Read memory from current PC 8B
value, increment PC
Write memory from current PC
value, increment PC
Note: The eZ80 CPU’s alternate register set (A’, F’, B’, C’, D’, E’, HL’) cannot be read directly.
The ZDI programmer must execute the exchange instruction (EXX) to gain access to the
alternate eZ80 CPU register set.
ZDI Bus Control Register
The ZDI Bus Control register controls bus requests during DEBUG mode. It enables or
disables bus acknowledge in ZDI DEBUG mode and allows ZDI to force assertion of the
BUSACK signal. This register must be written during ZDI Debug mode (that is, following
a BREAK). See Table 97.
Table 97. ZDI Bus Control Register (ZDI_BUS_CTL = 17h in the ZDI Register
Write-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
W
W
W
W
W
W
W
W
Note: W = Write-only.
PS013015-0316
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eZ80L92 MCU
Product Specification
176
Bit
Position
7
ZDI_BUSAK_EN
6
ZDI_BUSAK
[5:0]
Value Description
0
Bus requests by external peripherals using the BUSREQ
pin are ignored. The bus acknowledge signal, BUSACK, is
not asserted in response to any bus requests.
1
Bus requests by external peripherals using the BUSREQ
pin are accepted. A bus acknowledge occurs at the end of
the current ZDI operation. The bus acknowledge is
indicated by asserting the BUSACK pin in response to a
bus request.
0
Deassert the bus acknowledge pin (BUSACK) to return
control of the address and data buses back to ZDI.
1
Assert the bus acknowledge pin (BUSACK) to pass control
of the address and data buses to an external peripheral.
000000 Reserved.
Instruction Store 4:0 Registers
The ZDI Instruction Store registers are located in the ZDI Register Write-Only address
space. They can be written with instruction data for direct execution by the CPU. When
the ZDI_IS0 register is written, the ZLP12840 exits the ZDI BREAK state and executes a
single instruction. The Op Codes and operands for the instruction come from these
Instruction Store registers. The Instruction Store Register 0 is the first byte fetched,
followed by Instruction Store registers 1, 2, 3, and 4, as necessary.
Only the bytes the processor requires to execute the instruction must be stored in these
registers. Some eZ80 instructions, when combined with the MEMORY mode suffixes
(.SIS, .SIL, .LIS, or .LIL), require 6 bytes to operate. These 6-byte instructions cannot be
executed directly using the ZDI Instruction Store registers. See Table 98.
Note: The Instruction Store 0 register is located at a higher ZDI address than the other Instruction Store registers. This feature allows the use of the ZDI auto-address increment function to load and execute a multibyte instruction with a single data stream from the ZDI
master. Execution of the instruction commences with writing the final byte to ZDI_IS0.
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Product Specification
177
Table 98. Instruction Store 4:0 Registers (ZDI_IS4 = 21h, ZDI_IS3 = 22h,
ZDI_IS2 = 23h, ZDI_IS1 = 24h, and ZDI_IS0 = 25h in the ZDI Register WriteOnly Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: X = Undefined; W = Write.
Bit
Position
[7:0]
ZDI_IS4,
ZDI_IS3,
ZDI_IS2,
ZDI_IS1,
or
ZDI_IS0
Value
Description
00h–FFh These registers contain the Op Codes and operands
for immediate execution by the CPU following a Write
to ZDI_IS0. The ZDI_IS0 register contains the first Op
Code of the instruction. The remaining ZDI_ISx
registers contain any additional Op Codes or operand
dates required for execution of the required instruction.
ZDI Write Memory Register
A Write to the ZDI Write Memory register causes the ZLP12840 to write the 8-bit data to
the memory location specified by the current address in the program counter. In Z80
MEMORY mode, this address is {MBASE, PC[15:0]}. In ADL MEMORY mode, this
address is PC[23:0]. The program counter, PC, increments after each data Write. However,
the ZDI register address does not increment automatically when this register is accessed.
As a result, the ZDI master is allowed to write any number of data bytes by writing to this
address one time followed by any number of data bytes. See Table 99.
Table 99. ZDI Write Memory Register (ZDI_WR_MEM = 30h in the ZDI
Register Write-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
W
W
W
W
W
W
W
W
Note: X = Undefined; W = Write.
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Zilog Debug Interface
eZ80L92 MCU
Product Specification
178
Bit
Position
[7:0]
zdi_wr_mem
Value
Description
00h–FFh The 8-bit data that is transferred to the ZDI slave
following a Write to this address is written to the address
indicated by the current program counter. The program
counter is incremented following each 8 bits of data. In
Z80 MEMORY mode, ({MBASE, PC[15:0]}) ← 8 bits of
transferred data. In ADL MEMORY mode, (PC[23:0]) ←
8 bits of transferred data.
eZ80® Product ID Low and High Byte Registers
The eZ80 Product ID Low and High Byte registers combine to provide a means for an
external device to determine the particular eZ80 product being addressed. For the
ZLP12840, these two bytes, {ZDI_ID_H, ZDI_ID_L} return the value {00h, 06h}. See
Tables 100 and 101.
Table 100. eZ80® Product ID Low Byte Register (ZDI_ID_L = 00h in the ZDI
Register Read-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
1
1
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
Bit
Position
[7:0]
zdi_id_l
Value Description
06h
{ZDI_ID_H, ZDI_ID_L} = {00h, 06h} indicates the
ZLP12840 product.
Table 101. eZ80® Product ID High Byte Register (ZDI_ID_H = 01h in the ZDI
Register Read-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
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eZ80L92 MCU
Product Specification
179
Bit
Position
Value Description
[7:0]
zdi_id_H
00h
{ZDI_ID_H, ZDI_ID_L} = {00h, 06h} indicates the
ZLP12840 product.
eZ80® Product ID Revision Register
The eZ80 Product ID Revision register identifies the current revision of the ZLP12840
product. See Table 102.
Table 102. eZ80® Product ID Revision Register (ZDI_ID_REV = 02h in the ZDI
Register Read-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
X
X
X
X
X
X
X
X
CPU Access
R
R
R
R
R
R
R
R
Note: X = Undetermined; R = Read-only.
Bit
Position
[7:0]
zdi_id_rev
Value
Description
00h–FFh Identifies the current revision of the ZLP12840 product.
ZDI Status Register
The ZDI Status register provides current information about the ZLP12840 and the eZ80
CPU. See Table 103.
Table 103. ZDI Status Register (ZDI_STAT = 03h in the ZDI Register ReadOnly Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
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Zilog Debug Interface
eZ80L92 MCU
Product Specification
180
Bit
Position
Value Description
7
zdi_active
0
The CPU is not functioning in ZDI mode.
1
The CPU is currently functioning in ZDI mode.
6
0
Reserved.
5
halt_SLP
0
ZLP12840 is not currently in HALT or SLEEP mode.
1
ZLP12840 is currently in HALT or SLEEP mode.
0
The CPU is operating in Z80 MEMORY mode.
(ADL bit = 0).
1
The CPU is operating in ADL MEMORY mode.
(ADL bit = 1).
3
MADL
0
The CPU’s Mixed-Memory mode (MADL) bit is reset to 0.
1
The CPU’s Mixed-Memory mode (MADL) bit is set to 1.
2
IEF1
0
The CPU’s Interrupt Enable Flag 1 is reset to 0. Maskable
interrupts are disabled.
1
The CPU’s Interrupt Enable Flag 1 is set to 1. Maskable
interrupts are enabled.
00
Reserved.
4
ADL
[1:0]
Reserved
ZDI Read Registers—Low, High, and Upper
The ZDI register Read-Only address space offers Low, High, and Upper functions, which
contain the value read by a Read operation from the ZDI Read/Write Control register
(ZDI_RW_CTL). This data is valid only while in ZDI BREAK mode and only if the
instruction is read by a request from the ZDI Read/Write Control register. See Table 104.
Table 104. ZDI Read Registers—Low, High and Upper (ZDI_RD_L = 10h,
ZDI_RD_H = 11h, and ZDI_RD_U = 12h in the ZDI Register Read-Only
Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
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eZ80L92 MCU
Product Specification
181
Bit
Position
[7:0]
ZDI_RD_L,
ZDI_RD_H,
or
ZDI_RD_U
Value
Description
00h–FFh Values read from the memory location as requested by
the ZDI Read Control register during a ZDI Read
operation. The 24-bit value is supplied by {ZDI_RD_U,
ZDI_RD_H, ZDI_RD_L}.
ZDI Bus Status Register
The ZDI Bus Status register monitors BUSACKs during DEBUG mode. See Table 105.
Table 105. ZDI Bus Control Register (ZDI_BUS_STAT = 17h in the ZDI
Register Read-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
Bit
Position
7
ZDI_BUSAcK_En
6
ZDI_BUS_STAT
[5:0]
PS013015-0316
Value
Description
0
Bus requests by external peripherals using the
BUSREQ pin are ignored. The bus acknowledge signal,
BUSACK, is not asserted.
1
Bus requests by external peripherals using the
BUSREQ pin are accepted. A bus acknowledge occurs
at the end of the current ZDI operation. The bus
acknowledge is indicated by asserting the BUSACK pin.
0
Address and data buses are not relinquished to an
external peripheral. bus acknowledge is deasserted
(BUSACK pin is High).
1
Address and data buses are relinquished to an external
peripheral. bus acknowledge is asserted (BUSACK pin
is Low).
000000 Reserved.
Zilog Debug Interface
eZ80L92 MCU
Product Specification
182
ZDI Read Memory Register
When a Read is executed from the ZDI Read Memory register, the ZLP12840 fetches the
data from the memory address currently pointed to by the program counter, PC; the program counter is then incremented. In Z80 MEMORY mode, the memory address is
{MBASE, PC[15:0]}. In ADL MEMORY mode, the memory address is PC[23:0]. Refer
to the eZ80® CPU User Manual (UM0077) for more information regarding Z80 and ADL
MEMORY modes.
The program counter, PC, increments after each data Read. However, the ZDI register
address does not increment automatically when this register is accessed. As a result, the
ZDI master can read any number of data bytes out of memory through the ZDI Read
Memory register. See Table 106.
Table 106. ZDI Read Memory Register (ZDI_RD_MEM = 20h in the ZDI
Register Read-Only Address Space)
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
0
CPU Access
R
R
R
R
R
R
R
R
Note: R = Read-only.
Bit
Position
[7:0]
zdi_rd_mem
PS013015-0316
Value
Description
00h–FFh 8-bit data read from the memory address indicated by
the CPU’s program counter. In Z80 MEMORY mode,
8-bit data is transferred out from address {MBASE,
PC[15:0]}. In ADL Memory mode, 8-bit data is
transferred out from address PC[23:0].
Zilog Debug Interface
eZ80L92 MCU
Product Specification
183
On-Chip Instrumentation
On-Chip Instrumentation1 (OCI™) for the Zilog eZ80 CPU core enables powerful debugging features. The OCI provides run control, memory and register visibility, complex
breakpoints, and trace history features.
The OCI employs all the functions of the Zilog Debug Interface (ZDI) as described in the
ZDI section. It also adds the following debug features:
•
Control through a 4-pin JTAG port that conforms to IEEE Standard 1149.1 (Test Access Port and Boundary-Scan Architecture)2.
•
•
Complex break-point trigger functions.
•
•
Trace history buffer.
Break-point enhancements, such as the ability to:
– Define two break-point addresses that form a range.
– Break on masked data values.
– Start or stop trace.
– Assert a trigger output signal.
Software break-point instruction.
OCI has the following sections:
1. JTAG interface.
2. ZDI debug control.
3. Trace buffer memory.
4. Complex triggers.
OCI Activation
The OCI features clock initialization circuitry so that external debug hardware can be
detected during power up. The external debugger must drive the OCI clock pin (TCK)
Low at least two system clock cycles prior to the end of the RESET to activate the OCI
block. If TCK is High at the end of the RESET, the OCI block shuts down so that it does
not draw power in normal product operation. When the OCI is shut down, ZDI is enabled
directly and can be accessed through the clock (TCK) and data (TDI) pins. For more information on ZDI, see Zilog Debug Interface on page 160.
1. On-Chip Instrumentation and OCI are trademarks of First Silicon Solutions, Inc.
2. The eZ80L92 MCU does not contain the boundary scan register required for 1149.1 compliance.
PS013015-0316
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eZ80L92 MCU
Product Specification
184
OCI Interface
There are five dedicated pins on the ZLP12840 MCU for the OCI interface. Four pins
(TCK, TMS, TDI, and TDO) are required for IEEE Standard 1149.1-compatible JTAG
ports. The TRIGOUT pin provides additional testability features. Table 107 lists these five
OCI pins.
Table 107. OCI Pins
Symbol
Name
Type
Description
TCK
Clock.
Input
Asynchronous to the primary ZLP12840 system
clock. The TCK period but must be at least twice the
system clock period. During RESET, this pin is
sampled to select either OCI or ZDI DEBUG modes.
If Low during RESET, the OCI is enabled. If High
during RESET, the OCI is powered down and ZDI
DEBUG mode is enabled. When ZDI DEBUG mode
is active, this pin is the ZDI clock. On-chip pull-up
ensures a default value of 1 (High).
TMS
Test Mode Select
Input
This serial test mode input controls JTAG mode
selection. On-chip pull-up ensures a default value of
1 (High). The TMS signal is sampled on the rising
edge of the TCK signal.
TDI
Data In
Input
(OCI enabled)
Serial test data input. On-chip pull-up ensures a
default value of 1 (High). This pin is input-only when
the OCI is enabled. The input data is sampled on the
rising edge of the TCK signal.
I/O
(OCI disabled)
When the OCI is disabled, this pin functions as the
ZDA (ZDI Data) I/O pin.
TDO
Data Out
Output
The output data changes on the falling edge of the
TCK signal.
TRIGOUT
Trigger Output
Output
Generates an active High trigger pulse when valid
OCI trigger events occur. Output is tristate when no
data is being driven out.
PS013015-0316
On-Chip Instrumentation
eZ80L92 MCU
Product Specification
185
OCI Information Requests
For additional information regarding On-Chip Instrumentation, or to order OCI debug
tools, please contact:
First Silicon Solutions, Inc.
5440 SW Westgate Drive, Suite 240
Portland, OR 97221
Phone: (503) 292-6730
Fax: (503) 292-5840
www.fs2.com
PS013015-0316
On-Chip Instrumentation
eZ80L92 MCU
Product Specification
186
eZ80® CPU Instruction Set
Table 108 through Table 108 indicate the eZ80 CPU instructions available for use with the
ZLP12840 MCU. The instructions are grouped by class. A detailed information is
available in the eZ80 CPU User Manual.
Table 108. Arithmetic Instructions
Mnemonic
Instruction
ADC
Add with Carry
ADD
Add without Carry
CP
Compare with Accumulator
DAA
Decimal Adjust Accumulator
DEC
Decrement
INC
Increment
MLT
Multiply
NEG
Negate Accumulator
SBC
Subtract with Carry
SUB
Subtract without Carry
Table 108. Bit Manipulation Instructions
Mnemonic
Instruction
BIT
Bit Test
RES
Reset Bit
SET
Set Bit
Table 108. Block Transfer and Compare Instructions
PS013015-0316
Mnemonic
Instruction
CPD (CPDR)
Compare and Decrement (with Repeat)
CPI (CPIR)
Compare and Increment (with Repeat)
eZ80® CPU Instruction Set
eZ80L92 MCU
Product Specification
187
Table 108. Block Transfer and Compare Instructions
Mnemonic
Instruction
LDD (LDDR)
Load and Decrement (with Repeat)
LDI (LDIR)
Load and Increment (with Repeat)
Table 108. Exchange Instructions
Mnemonic
Instruction
EX
Exchange registers
EXX
Exchange CPU Multibyte register banks
Table 108. Input/Output Instructions
PS013015-0316
Mnemonic
Instruction
IN
Input from I/O
IN0
Input from I/O on Page 0
IND (INDR)
Input from I/O and Decrement (with Repeat)
INDRX
Input from I/O and Decrement Memory Address
with Stationary I/O Address
IND2 (IND2R)
Input from I/O and Decrement (with Repeat)
INDM (INDMR)
Input from I/O and Decrement (with Repeat)
INI (INIR)
Input from I/O and Increment (with Repeat)
INIRX
Input from I/O and Increment Memory Address
with Stationary I/O Address
INI2 (INI2R)
Input from I/O and Increment (with Repeat)
INIM (INIMR)
Input from I/O and Increment (with Repeat)
OTDM (OTDMR)
Output to I/O and Decrement (with Repeat)
OTDRX
Output to I/O and Decrement Memory Address
with Stationary I/O Address
OTIM (OTIMR)
Output to I/O and Increment (with Repeat)
OTIRX
Output to I/O and Increment Memory Address
with Stationary I/O Address
OUT
Output to I/O
eZ80® CPU Instruction Set
eZ80L92 MCU
Product Specification
188
Table 108. Input/Output Instructions
Mnemonic
Instruction
OUT0
Output to I/O on Page 0
OUTD (OTDR)
Output to I/O and Decrement (with Repeat)
OUTD2 (OTD2R)
Output to I/O and Decrement (with Repeat)
OUTI (OTIR)
Output to I/O and Increment (with Repeat)
OUTI2 (OTI2R)
Output to I/O and Increment (with Repeat)
TSTIO
Test I/O
Table 108. Load Instructions
Mnemonic
Instruction
LD
Load
LEA
Load Effective Address
PEA
Push Effective Address
POP
Pop
PUSH
Push
Table 108. Logical Instructions
Mnemonic
Instruction
AND
Logical AND
CPL
Complement Accumulator
OR
Logical OR
TST
Test Accumulator
XOR
Logical Exclusive OR
Table 108. Processor Control Instructions
PS013015-0316
Mnemonic
Instruction
CCF
Complement Carry Flag
DI
Disable Interrupts
eZ80® CPU Instruction Set
eZ80L92 MCU
Product Specification
189
Table 108. Processor Control Instructions
Mnemonic
Instruction
EI
Enable Interrupts
HALT
Halt
IM
Interrupt Mode
NOP
No Operation
RSMIX
Reset Mixed-Memory Mode Flag
SCF
Set Carry Flag
SLP
Sleep
STMIX
Set Mixed-Memory Mode Flag
Table 108. Program Control Instructions
Mnemonic
Instruction
CALL
Call Subroutine
CALL cc
Conditional Call Subroutine
DJNZ
Decrement and Jump if Nonzero
JP
Jump
JP cc
Conditional Jump
JR
Jump Relative
JR cc
Conditional Jump Relative
RET
Return
RET cc
Conditional Return
RETI
Return from Interrupt
RETN
Return from Nonmaskable interrupt
RST
Restart
Table 108. Rotate and Shift Instructions
PS013015-0316
Mnemonic
Instruction
RL
Rotate Left
RLA
Rotate Left–Accumulator
eZ80® CPU Instruction Set
eZ80L92 MCU
Product Specification
190
Table 108. Rotate and Shift Instructions
PS013015-0316
Mnemonic
Instruction
RLC
Rotate Left Circular
RLCA
Rotate Left Circular–Accumulator
RLD
Rotate Left Decimal
RR
Rotate Right
RRA
Rotate Right–Accumulator
RRC
Rotate Right Circular
RRCA
Rotate Right Circular–Accumulator
RRD
Rotate Right Decimal
SLA
Shift Left Arithmetic
SRA
Shift Right Arithmetic
SRL
Shift Right Logical
eZ80® CPU Instruction Set
eZ80L92 MCU
Product Specification
191
Opcode Map
Table 109 through Table 115 indicate the hex values for the eZ80 instructions.
Table 109. Opcode Map—First Opcode
Legend
Lower opcode Nibble
Upper
opcode
Nibble
4
AND
A
A,H
First Operand
0
0
NOP
1
DJNZ
d
2
JR
NZ,d
3
JR
NC,d
4
Upper Nibble (Hex)
5
6
7
8
9
A
B
.SIS
suffix
LD
D,B
LD
H,B
LD
(HL),B
ADD
A,B
SUB
A,B
AND
A,B
OR
A,B
C
RET
NZ
D
RET
NC
E
RET
PO
F
RET
P
Notes:
Mnemonic
Second Operand
Lower Nibble (Hex)
1
2
3
4
5
6
7
8
9
A
B
LD
EX
ADD
LD
DEC
LD
INC
INC
DEC
LD
BC,
RLCA
AF,AF’ HL,BC A,(BC)
BC
(BC),A
BC
B
B
B,n
Mmn
LD
JR
ADD
LD
DEC
LD
INC
INC
DEC
LD
DE,
RLA
d
HL,DE A,(DE)
DE
(DE),A
DE
D
D
D,n
Mmn
LD
LD
LD
JR
ADD
INC
INC
DEC
LD
DEC
HL,
(Mmn),
DAA
HL,
Z,d
HL,HL
HL
H
H
H,n
HL
Mmn
HL
(Mmn)
LD
LD
LD
INC
INC
DEC
JR
ADD
LD
DEC
SP,
(Mmn),
SCF
A,
SP
(HL)
(HL)
CF,d
HL,SP
(HL),n
SP
Mmn
A
(Mmn)
LD
LD
LD
LD
LD
LD
LD
LD
.LIS
LD
LD
B,C
B,D
B,E
B,H
B,L
B,(HL)
B,A
C,B
suffix
C,D
C,E
LD
.SIL
LD
LD
LD
LD
LD
LD
LD
LD
.LIL
D,C
suffix
D,E
D,H
D,L
D,(HL)
D,A
E,B
E,C
E,D
suffix
LD
LD
LD
LD
LD
LD
LD
LD
LD
LD
LD
H,C
H,D
H,E
H,H
H,L
H,(HL)
H,A
L,B
L,C
L,D
L,E
LD
LD
LD
LD
LD
LD
LD
LD
LD
LD
HALT
(HL),C (HL),D (HL),E (HL),H (HL),L
(HL),A
A,B
A,C
A,D
A,E
ADD
ADD
ADD
ADD
ADD
ADD
ADD
ADC
ADC
ADC
ADC
A,C
A,D
A,E
A,H
A,L
A,(HL)
A,A
A,B
A,C
A,D
A,E
SUB
SUB
SUB
SUB
SUB
SUB
SBC
SBC
SBC
SBC
SUB
A,C
A,D
A,E
A,L
A,(HL)
A,A
A,B
A,C
A,D
A,E
A,H
AND
AND
AND
AND
AND
AND
AND
XOR
XOR
XOR
XOR
A,C
A,D
A,E
A,H
A,L
A,(HL)
A,A
A,B
A,C
A,D
A,E
OR
OR
OR
OR
OR
OR
OR
CP
CP
CP
CP
A,C
A,D
A,E
A,H
A,L
A,(HL)
A,A
A,B
A,C
A,D
A,E
JP
JP
CALL
Table
RST
RET
POP
JP
PUSH
ADD
RET
Z,
NZ,
NZ,
00h
Z
BC
Mmn
BC
A,n
110
Mmn
Mmn
Mmn
JP
CALL
JP
POP
OUT
PUSH
SUB
RST
RET
IN
NC,
NC,
EXX
CF,
DE
(n),A
DE
A,n
10h
CF
A,(n)
Mmn
Mmn
Mmn
JP
CALL
JP
POP
EX
PUSH
AND
RST
RET
JP
EX
PO,
PO,
PE,
HL
(SP),HL
HL
A,n
20h
PE
(HL)
DE,HL
Mmn
Mmn
Mmn
JP
CALL
JP
POP
PUSH
OR
RST
RET
LD
P,
DI
P,
M,
EI
AF
AF
A,n
30h
M
SP,HL
Mmn
Mmn
Mmn
n = 8-bit data; Mmn = 16- or 24-bit addr or data; d = 8-bit two’s-complement displacement.
PS013015-0316
C
D
E
F
INC
C
DEC
C
LD
C,n
RRCA
INC
E
DEC
E
LD
E,n
RRA
INC
L
DEC
L
LD
L,n
CPL
INC
A
DEC
A
LD
A,n
CCF
LD
C,H
LD
E,H
LD
L,H
LD
A,H
ADC
A,H
SBC
A,H
XOR
A,H
CP
A,H
CALL
Z,
Mmn
CALL
CF,
Mmn
CALL
PE,
Mmn
CALL
M,
Mmn
LD
C,L
LD
E,L
LD
L,L
LD
A,L
ADC
A,L
SBC
A,L
XOR
A,L
CP
A,L
LD
C,(HL)
LD
E,(HL)
LD
L,(HL)
LD
A,(HL)
ADC
A,(HL)
SBC
A,(HL)
XOR
A,(HL)
CP
A,(HL)
LD
C,A
LD
E,A
LD
L,A
LD
A,A
ADC
A,A
SBC
A,A
XOR
A,A
CP
A,A
CALL
Mmn
ADC
A,n
RST
08h
Table
111
Table
112
Table
113
SBC
A,n
RST
18h
XOR
A,n
RST
28h
CP
A,n
RST
38h
Opcode Map
eZ80L92 MCU
Product Specification
192
Table 110. Opcode Map—Second Opcode after 0CBh
Legend
Lower Nibble of 2nd cpcode
Upper
Nibble
of Second
cpcode
4
A RES
4,H
Mnemonic
First Operand
Second Operand
Lower Nibble (Hex)
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
0
RLC
B
RLC
C
RLC
D
RLC
E
RLC
H
RLC
L
RLC
(HL)
RLC
A
RRC
B
RRC
C
RRC
D
RRC
E
RRC
H
RRC
L
RRC
(HL)
RRC
A
1
RL
B
RL
C
RL
D
RL
E
RL
H
RL
L
RL
(HL)
RL
A
RR
B
RR
C
RR
D
RR
E
RR
H
RR
L
RR
(HL)
RR
A
2
SLA
B
SLA
C
SLA
D
SLA
E
SLA
H
SLA
L
SLA
(HL)
SLA
A
SRA
B
SRA
C
SRA
D
SRA
E
SRA
H
SRA
L
SRA
(HL)
SRA
A
SRL
B
SRL
C
SRL
D
SRL
E
SRL
H
SRL
L
SRL
(HL)
SRL
A
Upper Nibble (Hex)
3
4
BIT
0,B
BIT
0,C
BIT
0,D
BIT
0,E
BIT
0,H
BIT
0,L
BIT
0,(HL)
BIT
0,A
BIT
1,B
BIT
1,C
BIT
1,D
BIT
1,E
BIT
1,H
BIT
1,L
BIT
1,(HL)
BIT
1,A
5
BIT
2,B
BIT
2,C
BIT
2,D
BIT
2,E
BIT
2,H
BIT
2,L
BIT
2,(HL)
BIT
2,A
BIT
3,B
BIT
3,C
BIT
3,D
BIT
3,E
BIT
3,H
BIT
3,L
BIT
3,(HL)
BIT
3,A
6
BIT
4,B
BIT
4,C
BIT
4,D
BIT
4,E
BIT
4,H
BIT
4,L
BIT
4,(HL)
BIT
4,A
BIT
5,B
BIT
5,C
BIT
5,D
BIT
5,E
BIT
5,H
BIT
5,L
BIT
5,(HL)
BIT
5,A
7
BIT
6,B
BIT
6,C
BIT
6,D
BIT
6,E
BIT
6,H
BIT
6,L
BIT
6,(HL)
BIT
6,A
BIT
7,B
BIT
7,C
BIT
7,D
BIT
7,E
BIT
7,H
BIT
7,L
BIT
7,(HL)
BIT
7,A
8
RES
0,B
RES
0,C
RES
0,D
RES
0,E
RES
0,H
RES
0,L
RES
0,(HL)
RES
0,A
RES
1,B
RES
1,C
RES
1,D
RES
1,E
RES
1,H
RES
1,L
RES
1,(HL)
RES
1,A
9
RES
2,B
RES
2,C
RES
2,D
RES
2,E
RES
2,H
RES
2,L
RES
2,(HL)
RES
2,A
RES
3,B
RES
3,C
RES
3,D
RES
3,E
RES
3,H
RES
3,L
RES
3,(HL)
RES
3,A
A
RES
4,B
RES
4,C
RES
4,D
RES
4,E
RES
4,H
RES
4,L
RES
4,(HL)
RES
4,A
RES
5,B
RES
5,C
RES
5,D
RES
5,E
RES
5,H
RES
5,L
RES
5,(HL)
RES
5,A
B
RES
6,B
RES
6,C
RES
6,D
RES
6,E
RES
6,H
RES
6,L
RES
6,(HL)
RES
6,A
RES
7,B
RES
7,C
RES
7,D
RES
7,E
RES
7,H
RES
7,L
RES
7,(HL)
RES
7,A
C
SET
0,B
SET
0,C
SET
0,D
SET
0,E
SET
0,H
SET
0,L
SET
0,(HL)
SET
0,A
SET
1,B
SET
1,C
SET
1,D
SET
1,E
SET
1,H
SET
1,L
SET
1,(HL)
SET
1,A
D
SET
2,B
SET
2,C
SET
2,D
SET
2,E
SET
2,H
SET
2,L
SET
2,(HL)
SET
2,A
SET
3,B
SET
3,C
SET
3,D
SET
3,E
SET
3,H
SET
3,L
SET
3,(HL)
SET
3,A
E
SET
4,B
SET
4,C
SET
4,D
SET
4,E
SET
4,H
SET
4,L
SET
4,(HL)
SET
4,A
SET
5,B
SET
5,C
SET
5,D
SET
5,E
SET
5,H
SET
5,L
SET
5,(HL)
SET
5,A
F
SET
6,B
SET
6,C
SET
6,D
SET
6,E
SET
6,H
SET
6,L
SET
6,(HL)
SET
6,A
SET
7,B
SET
7,C
SET
7,D
SET
7,E
SET
7,H
SET
7,L
SET
7,(HL)
SET
7,A
Notes:
n = 8-bit data; Mmn = 16- or 24-bit addr or data; d = 8-bit two’s-complement displacement.
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
193
Table 111. Opcode Map—Second Opcode After 0DDh
Legend
Lower Nibble of 2nd opcode
Upper
Nibble
of Second
opcode
9
LD
F
SP,IX
Mnemonic
Second Operand
First Operand
Lower Nibble (Hex)
Upper Nibble (Hex)
0
1
2
3
4
5
6
7
8
9
0
LD BC,
(IX+d)
ADD
IX,BC
1
LD DE,
(IX+d)
ADD
IX,DE
2
LD
IX,
Mmn
3
LD IY,
(IX+d)
LD
(Mmn),
IX
INC
IX
INC
IXH
DEC
IXH
LD
IXH,n
LD HL,
(IX+d)
ADD
IX,IX
INC
(IX+d)
DEC
(IX+d)
LD (IX
+d),n
LD IX,
(IX+d)
ADD
IX,SP
A
B
C
D
E
LD
IX,
(Mmn)
DEC
IX
INC
IXL
DEC
IXL
LD
IXL,n
4
LD
LD B,
LD B,IXL
B,IXH
(IX+d)
LD
(IX+d),
IY
LD
LD C,
LD C,IXL
C,IXH
(IX+d)
5
LD
LD D,
LD D,IXL
D,IXH
(IX+d)
LD
LD E,
LD E,IXL
E,IXH
(IX+d)
6
7
LD
IXH,B
LD
IXH,C
LD
IXH,D
LD H,
LD
LD
LD
IXH,E IXH,IXH IXH,IXL (IX+d)
LD
LD
LD
LD
LD
LD
(IX+d),B (IX+d),C (IX+d),D (IX+d),E (IX+d),H (IX+d),L
LD
LD
LD
LD IXL,BLD IXL,CLD IXL,DLD IXL,E
IXH,A
IXL,IXH IXL,IXL
LD
(IX+d),A
F
LD
(IX+d),
BC
LD
(IX+d),
DE
LD
(IX+d),
HL
LD
(IX+d),
IX
LD L,
LD IXL,A
(IX+d)
LD
LD A,
LD A,IXL
A,IXH
(IX+d)
8
ADD
A,IXH
ADD
A,IXL
ADD A,
(IX+d)
ADC
A,IXH
ADC
A,IXL
ADC A,
(IX+d)
9
SUB
A,IXH
SUB
A,IXL
SUB A,
(IX+d)
SBC
A,IXH
SBC
A,IXL
SBC A,
(IX+d)
A
AND
A,IXH
AND
A,IXL
AND A,
(IX+d)
XOR
A,IXH
XOR
A,IXL
XOR A,
(IX+d)
B
OR
A,IXH
OR
A,IXL
OR A,
(IX+d)
CP
A,IXH
CP
A,IXL
CP A,
(IX+d)
Table
114
C
D
E
POP
IX
EX
(SP),IX
PUSH
IX
JP
(IX)
LD
SP,IX
F
Notes: n = 8-bit data; Mmn = 16- or 24-bit addr or data; d = 8-bit two’s-complement displacement.
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
194
Table 112. Opcode Map—Second Opcode After 0EDh
Legend
Lower Nibble of 2nd opcode
Upper
Nibble
of Second
opcode
2
SBC
4 HL,BC
First Operand
Mnemonic
Second Operand
Lower Nibble (Hex)
0
IN0
B,(n)
1
2
3
OUT0 LEA BC, LEA BC,
(n),B
IX+d
IY+d
4
TST
A,B
1
IN0
D,(n)
OUT0 LEA DE, LEA DE,
(n),D
IX+d
IY+d
2
IN0
H,(n)
OUT0 LEA HL LEA HL
(n),H
,IX+d
,IY+d
0
3
4
Upper Nibble (Hex)
5
6
7
5
7
LD BC,
(HL)
8
IN0
C,(n)
9
OUT0
(n),C
TST
A,D
LD DE,
(HL)
IN0
E,(n)
OUT0
(n),E
TST
A,E
LD(HL),
DE
TST
A,H
LD HL,
(HL)
IN0
L,(n)
OUT0
(n),L
TST
A,L
LD (HL),
HL
LD IX,
(HL)
IN0
A,(n)
OUT0
(n),A
TST
A,A
LD LD (HL),
(HL),IY
IX
IM 0
LD
I,A
IN
C,(C)
OUT
(C),C
ADC
HL,BC
IM 1
LD
A,I
IN
E,(C)
OUT
(C),E
ADC
HL,DE
PEA
IY+d
RRD
IN
L,(C)
OUT
(C),L
ADC
HL,HL
IN
A,(C)
OUT
(C),A
ADC
HL,SP
LEA IX LEA IY TST
,IX+d
,IY+d A,(HL)
LD
IN
OUT
SBC
(Mmn), NEG
RETN
B,(BC) (BC),B HL,BC
BC
LD
IN
OUT
SBC
LEA IX, LEA IY,
(Mmn),
D,(BC) (BC),D HL,DE
IY+d
IX+d
DE
LD
IBN
OUT
SBC
PEA
TST
(Mmn),
H,(C) (BC),H HL,HL
A,n
IX+d
HL
LD
SBC
TSTIO
(Mmn),
HL,SP
n
SP
6
LD IY,
(HL)
8
INIM
9
OTIM
INIMR OTIMR
SLP
INI2
A
INDM
INI2R
B
LD
BC,
(Mmn)
LD
DE,
(Mmn)
LD
HL,
(Mmn)
LD
SP,
(Mmn)
OTDM
C
TST
A,C
MLT
BC
E
MLT
HL
MLT
SP
LD
MB,A
F
LD (HL),
BC
LD
R,A
RETI
MLT
DE
IM 2
LD
A,R
LD
A,MB
RLD
STMIX RSMIX
IND2
INDMR OTDMR IND2R
A
LDI
CPI
INI
OUTI
OUTI2
LDD
CPD
IND
OUTD OUTD2
B
LDIR
CPIR
INIR
OTIR
OTI2R
LDDR
CPDR
INDR
OTDR OTD2R
INIRX
OTIRX
C
D
INDRX OTDRX
D
E
F
Notes: n = 8-bit data; Mmn = 16- or 24-bit addr or data; d = 8-bit two’s-complement displacement
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
195
Table 113. Opcode Map—Second Opcode After 0FDh
Legend
Lower Nibble of 2nd opcode
Upper
Nibble
of Second
opcode
9
F LD
SP,IY
First Operand
Mnemonic
Second Operand
Lower Nibble (Hex)
0
1
2
3
4
5
6
0
1
LD
LD
(Mmn),I
IY,Mmn
Y
LD IX,
(IY+d)
2
Upper Nibble (Hex)
3
INC
IY
7
LD BC,
(IY+d)
8
9
ADD
IY,BC
LD DE,
(IY+d)
ADD
IY,DE
INC
IYH
DEC
IYH
LD
IYH,n
LD HL,
(IY+d)
ADD
IY,IY
INC
(IY+d)
DEC
(IY+d)
LD (IY
+d),n
LD IY,
(IY+d)
ADD
IY,SP
A
B
C
D
E
LD (IY
+d),DE
LD
IY,
(Mmn)
DEC
IY
INC
IYL
DEC
IYL
LD (IY
+d),HL
LD (IY
+d),IX
LD (IY
+d),IY
LD B,
LD
LD B,IYL
(IY+d)
B,IYH
LD
C,IYH
5
LD
D,IYH
LD E,
LD
LD E,IYL
(IY+d)
E,IYH
LD D,
(IY+d)
6
LD
IYH,B
LD
IYH,C
LD
IYH,D
LD
LD
LD
LD H,
IYH,E IYH,IYH IYH,IYL (IY+d)
LD
LD
LD IYL,B
IYH,A
IYL,C
7
LD (IY
+d),B
LD (IY
+d),C
LD (IY
+d),D
LD (IY
+d),E
LD (IY
+d),A
LD
C,IYL
LD
IYL,n
4
LD
D,IYL
F
LD (IY
+d),BC
LD C,
(IY+d)
LD
LD
LD L,
LD
LD IYL,A
LD IYL,E
IYL,IYH IYL,IYL (IY+d)
IYL,D
LD A,
LD
LD A,IYL
(IY+d)
A,IYH
LD (IY
+d),H
LD (IY
+d),L
8
ADD
A,IYH
ADD
A,IYL
ADD A,
(IY+d)
ADC
A,IYH
ADC
A,IYL
ADC A,
(IY+d)
9
SUB
A,IYH
SUB
A,IYL
SUB A,
(IY+d)
SBC
A,IYH
SBC
A,IYL
SBC A,
(IY+d)
A
AND
A,IYH
AND
A,IYL
AND A,
(IY+d)
XOR
A,IYH
XOR
A,IYL
XOR A,
(IY+d)
B
OR
A,IYH
OR
A,IYL
OR A,
(IY+d)
CP
A,IYH
CP
A,IYL
CP A,
(IY+d)
Table
115
C
D
E
POP
IY
EX
(SP),IY
PUSH
IY
JP
(IY)
LD
SP,IY
F
Notes: n = 8-bit data; Mmn = 16- or 24-bit addr or data; d = 8-bit two’s-complement displacement.
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
196
Table 114. Opcode Map—Fourth Byte After 0DDh, 0CBh, and dd
Legend
Lower Nibble of 4th Byte
Upper
Nibble
of Fourth
Byte
6
BIT
4 0,(IX+d)
First Operand
Mnemonic
Second Operand
Lower Nibble (Hex)
0
1
2
3
4
5
6
8
9
A
B
C
D
E
0
RRC
(IX+d)
1
RL
(IX+d)
RR
(IX+d)
2
SLA
(IX+d)
SRA
(IX+d)
F
SRL
(IX+d)
3
Upper Nibble (Hex)
7
RLC
(IX+d)
4
BIT 0,
(IX+d)
BIT 1,
(IX+d)
5
BIT 2,
(IX+d)
BIT 3,
(IX+d)
6
BIT 4,
(IX+d)
BIT 5,
(IX+d)
7
BIT 6,
(IX+d)
BIT 7,
(IX+d)
8
RES 0,
(IX+d)
RES 1,
(IX+d)
9
RES 2,
(IX+d)
RES 3,
(IX+d)
A
RES 4,
(IX+d)
RES 5,
(IX+d)
B
RES 6,
(IX+d)
RES 7,
(IX+d)
C
SET 0,
(IX+d)
SET 1,
(IX+d)
D
SET 2,
(IX+d)
SET 3,
(IX+d)
E
SET 4,
(IX+d)
SET 5,
(IX+d)
F
SET 6,
(IX+d)
SET 7,
(IX+d)
Notes: d = 8-bit two’s-complement displacement.
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
197
Table 115. Opcode Map—Fourth Byte After 0FDh, 0CBh, and dd*
Legend
Lower Nibble of 4th Byte
Upper
Nibble
of Fourth
Byte
4
First Operand
6
BIT
Mnemonic
0,(IY+d)
Second Operand
Lower Nibble (Hex)
0
1
0
2
3
4
5
6
RLC
(IY+d)
8
9
A
B
C
D
E
RRC
(IY+d)
1
RL
(IY+d)
RR
(IY+d)
2
SLA
(IY+d)
SRA
(IY+d)
F
SRL
(IY+d)
3
Upper Nibble (Hex)
7
4
BIT 0,
(IY+d)
BIT 1,
(IY+d)
5
BIT 2,
(IY+d)
BIT 3,
(IY+d)
6
BIT 4,
(IY+d)
BIT 5,
(IY+d)
7
BIT 6,
(IY+d)
BIT 7,
(IY+d)
8
RES 0,
(IY+d)
RES 1,
(IY+d)
9
RES 2,
(IY+d)
RES 3,
(IY+d)
A
RES 4,
(IY+d)
RES 5,
(IY+d)
B
RES 6,
(IY+d)
RES 7,
(IY+d)
C
SET 0,
(IY+d)
SET 1,
(IY+d)
D
SET 2,
(IY+d)
SET 3,
(IY+d)
E
SET 4,
(IY+d)
SET 5,
(IY+d)
F
SET 6,
(IY+d)
SET 7,
(IY+d)
Notes: d = 8-bit two’s-complement displacement.
PS013015-0316
Opcode Map
eZ80L92 MCU
Product Specification
198
On-Chip Oscillators
The eZ80L92 MCU features two on-chip oscillators for use with an external crystal.
The primary oscillator generates the system clock for the internal CPU and for the majority of the on-chip peripherals. Alternatively, the XIN input pin can accept a CMOS-level
clock input signal. If an external clock generator is used, the XOUT pin must be left
disconnected. The secondary oscillator can drive a 32 kHz crystal to generate the
time-base for the real time clock.
20 MHz Primary Crystal Oscillator Operation
Figure 44 illustrates a recommended configuration for connection with an external
20 MHz, fundamental-mode, and parallel-resonant crystal. Table 116 lists recommended
crystal specifications. Resistor R1 limits total power dissipation by the crystal. Printed
circuit board layout must add not more than 4 pF of stray capacitance to either the XIN or
XOUT pins. If oscillation does not occur, reduce the values of capacitors C1 and C2 to
decrease loading.
On-Chip Oscillator
XIN
XOUT
20 MHz Crystal
(Fundamental Mode)
C2 = 22 pF
R2 = 100 K‰
R1 = 220 ‰
C2 = 22 pF
Figure 44. Recommended Crystal Oscillator Configuration (20 MHz operation)
PS013015-0316
On-Chip Oscillators
eZ80L92 MCU
Product Specification
199
Table 116. Recommended Crystal Oscillator Specifications
(20 MHz Operation)
Parameter
Value
Units
Frequency
20
MHz
Resonance
Parallel
Mode
Comments
Fundamental
Series Resistance (RS)
25
Ω
Maximum
Load Capacitance (CL)
20
pF
Maximum
Shunt Capacitance (C0)
7
pF
Maximum
Drive Level
1
mW
Maximum
32 kHz Real Time Clock Crystal Oscillator Operation
Figure 45 illustrates a recommended configuration for connecting the real time clock
oscillator with an external 32 kHz, fundamental-mode, parallel-resonant crystal. Table 117
lists the recommended crystal specifications. A printed circuit board layout must add no
more than 4 pF of stray capacitance to either the RTC_XIN or RTC_XOUT pins. If oscillation does not occur, reduce the values of capacitors C1 and C2 to decrease loading.
An on-chip MOS resistor sets the crystal drive current limit. This configuration does not
requires an external bias resistor across the crystal. An on-chip MOS resistor provides the
biasing.
On-Chip Oscillator
RTC_XIN
RTC_XOUT
32 kHz Crystal
(Fundamental Mode)
C2 = 18 pF
R1 = 220 ‰
C2 = 18 pF
Figure 45. Recommended Crystal Oscillator Configuration (32 kHz operation)
PS013015-0316
On-Chip Oscillators
eZ80L92 MCU
Product Specification
200
Table 117. Recommended Crystal Oscillator Specifications
(32 kHz Operation)
Parameter
Value
Units
Comments
Frequency
32
kHz
32768 Hz
Resonance
Parallel
Mode
PS013015-0316
Fundamental
Series Resistance (RS)
40
kΩ
Maximum
Load Capacitance (CL)
12.5
pF
Maximum
Shunt Capacitance (C0)
3
pF
Maximum
Drive Level
1
µW
Maximum
On-Chip Oscillators
eZ80L92 MCU
Product Specification
201
Electrical Characteristics
Absolute Maximum Ratings
A stress greater than listed in Table 118 may or may not cause permanent damage to the
device. Operation of the device at any condition above those indicated in the operational
sections of these specifications is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability. For improved reliability,
unused inputs should be tied to one of the supply voltages (VDD or VSS).
Table 118. Absolute Maximum Ratings
Min
Stress
Max
Stress
Units
Notes
Ambient temperature under bias (ºC)
–40
+105
C
1
Storage temperature (ºC)
–65
+150
C
Voltage on any pin with respect to VSS
–0.3
+6.0
V
Voltage on VDD pin with respect to VSS
–0.3
+6.0
V
Total power dissipation
520
mW
Maximum current out of VSS
145
mA
Maximum current into VDD
145
mA
Parameter
Maximum current on input and/or inactive output pin
–15
+15
µA
Maximum output current from active output pin
–8
+8
mA
2
Notes:
1. Operating temperature is specified in DC Characteristics.
2. This voltage applies to all pins except where noted otherwise.
DC Characteristics
Table 119 lists the DC characteristics of the ZLP12840 MCU. Figure 46 and Figure 47
plot supply current values against CPU frequency and wait states.
PS013015-0316
Electrical Characteristics
eZ80L92 MCU
Product Specification
202
Table 119. DC Characteristics
TA =
0 ºC to 70 ºC
TA =
–40 ºC to 105 ºC
Symbol
Parameter
Min
Max
Min
Max
VDD
Supply Voltage
3.0
3.6
3.0
3.6
V
VIL
Low Level
Input Voltage
–0.3
0.8
–0.3
0.8
V
VIH
High Level
Input Voltage
0.7 x VDD
5.5
0.7 x VDD
5.5
V
VOL
Low Level
Output Voltage
0.4
V
VDD = 3.0 V;
IOL = 1 mA
VOH
High Level
Output Voltage
2.4
V
VDD = 3.0 V;
IOH = –1 mA
IIL
Input Leakage
Current
–10
+10
–10
+10
µA
VDD = 3.6V;
VIN = VDD or VSS1
ITL
Tristate Leakage
Current
–10
+10
–10
+10
µA
VDD = 3.6 V
IDD
Power Dissipation
(normal operation)
100
100
mA
F = 20 MHz
145
145
mA
F = 50 MHz
Power Dissipation
(HALT mode)
10
10
mA
F = 20 MHz
20
20
mA
F = 50 MHz
Power Dissipation
(SLEEP mode)
10
25
µA
Internal clocks
stopped
RTC_VDD RTC Supply
Voltage
IRTC
RTC Supply
Current
0.4
2.4
Units Conditions
3.0
3.6
3.0
3.6
V
2.5
typical
10
2.5
typical
10
µA
Supply current into
RTC_VDD
Notes:
1. This condition excludes all pins with on-chip pull-ups when driven Low.
PS013015-0316
DC Characteristics
eZ80L92 MCU
Product Specification
203
140
120
100
0 WAIT
80
2 WAIT
60
7 WAIT
40
20
0
0
10
20
30
40
50
60
Figure 46. ICC vs. Frequency (Typical at 3.3 V, 25 ºC)
Current ( mA )
140.0
120.0
100.0
10 MHz
80.0
60.0
30 MHz
20 MHz
40 MHZ
40.0
20.0
50 MHZ
Log. (10 MHz)
0.0
0
1
2
3
4
5
6
7
8
Log. (50 MHZ)
WAIT States
Figure 47. ICC vs. WAIT (Typical at 3.3 V, 25 ºC)
AC Characteristics
The section provides information on the AC characteristics and timing. All AC timing
information assumes a standard load of 50 pF on all outputs. See Table 120.
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
204
Table 120. AC Characteristics
TA =
0 ºC to 70 ºC
Symbol Parameter
Min
Max
TXIN
System Clock
Cycle Time
TXINH
System Clock
High Time
10
TXINL
System Clock
Low Time
TXINR
TXINF
Min
Max
20
Units
Conditions
ns
VDD = 3.0 – 3.6 V
10
ns
VDD = 3.0 – 3.6 V;
TCLK = 50 ns
10
10
ns
VDD = 3.0 – 3.6 V;
TCLK = 50 ns
System Clock
Rise Time
3
3
ns
VDD = 3.0 – 3.6 V;
TCLK = 50 ns
System Clock
Fall Time
3
3
ns
VDD = 3.0 – 3.6 V;
TCLK = 50 ns
PS013015-0316
20
TA =
–40 ºC to 105 ºC
AC Characteristics
eZ80L92 MCU
Product Specification
205
External Memory Read Timing
Figure 48 and Table 121 illustrate the timing for external Reads.
TCLK
X IN
T1
T2
ADDR[23:0]
T3
T4
DATA[7:0]
(input)
T5
T6
CSx
T7
T8
T9
T10
MREQ
RD
Figure 48. External Memory Read Timing
Table 121. External Read Timing
20 MHz (ns)
Parameter
Description
T1
50 MHz (ns)
Min
Max
Min
Max
Clock Rise to ADDR Valid Delay
—
10.2
—
10.2
T2
Clock Rise to ADDR Hold Time
2.4
—
2.4
—
T3
Input DATA Valid to Clock Rise Setup Time
1.0
—
1.0
—
T4
DATA Hold Time from Clock Rise
2.4
—
2.4
—
T5
Clock Rise to CSx Assertion Delay
3.2
10.3
3.2
10.3
T6
Clock Rise to CSx Deassertion Delay
2.9
9.7
2.9
9.7
T7
Clock Rise to MREQ Assertion Delay
2.8
9.6
2.8
9.6
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
206
Table 121. External Read Timing (Continued)
20 MHz (ns)
50 MHz (ns)
Parameter
Description
Min
Max
Min
Max
T8
Clock Rise to MREQ Deassertion Delay
2.6
6.9
2.6
6.9
T9
Clock Rise to RD Assertion Delay
3.0
9.8
3.0
9.8
T10
Clock Rise to RD Deassertion Delay
2.6
7.1
2.6
7.1
External Memory Write Timing
Figure 49 and Table 122 illustrate the timing for external Writes.
TCLK
X IN
T2
T1
ADDR[23:0]
T3
T4
DATA[7:0]
(output)
T5
T6
CSx
T7
T8
MREQ
T9
T10
WR
Figure 49. External Memory Write Timing
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
207
Table 122. External Write Timing
20 MHz (ns)
Parameter
Description
T1
50 MHz (ns)
Min
Max
Min
Max
Clock Rise to ADDR Valid Delay
—
10.2
—
10.2
T2
Clock Rise to ADDR Hold Time
2.4
—
2.4
—
T3
Clock Fall to Output DATA Valid Delay
—
6
—
6
T4
DATA Hold Time from Clock Rise
2.4
—
2.4
—
T5
Clock Rise to CSx Assertion Delay
3.2
10.3
3.2
10.3
T6
Clock Rise to CSx Deassertion Delay
2.9
9.7
2.9
9.7
T7
Clock Rise to MREQ Assertion Delay
2.8
9.6
2.8
9.6
T8
Clock Rise to MREQ Deassertion Delay
2.6
6.9
2.6
6.9
T9
Clock Fall to WR Assertion Delay
1.5
5.0
1.5
5.0
T10
Clock Rise to WR Deassertion Delay*
1.4
3.6
1.4
3.6
Note: *At the conclusion of a Write cycle, de-assertion of WR always occurs before any change to ADDR, DATA, CSx,
or MREQ. In certain applications, the de-assertion of WR can be concurrent with ADDR, DATA, CSx, or MREQ
when buffering is used off-chip.
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
208
External I/O Read Timing
Figure 50 and Table 123 diagram the timing for external I/O Reads.
TCLK
X IN
T1
T2
ADDR[23:0]
T3
T4
DATA[7:0]
(input)
T5
T6
CSx
T7
T8
T9
T10
IORQ
RD
Figure 50. External I/O Read Timing
Table 123. External I/O Read Timing
20 MHz (ns)
Parameter
Description
T1
50 MHz (ns)
Min
Max
Min
Max
Clock Rise to ADDR Valid Delay
—
6.9
—
6.9
T2
Clock Rise to ADDR Hold Time
2.2
—
2.2
—
T3
Input DATA Valid to Clock Rise Setup Time
0.4
—
0.4
—
T4
Clock Rise to DATA Hold Time
1.3
—
1.3
—
T5
Clock Rise to CSx Assertion Delay
2.6
10.8
2.6
10.8
T6
Clock Rise to CSx Deassertion Delay
2.4
8.8
2.4
8.8
T7
Clock Rise to IORQ Assertion Delay
2.6
7.0
2.6
7.0
T8
Clock Rise to IORQ Deassertion Delay
2.3
6.3
2.3
6.3
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
209
Table 123. External I/O Read Timing (Continued)
20 MHz (ns)
Min
Max
50 MHz (ns)
Parameter
Description
Min
Max
T9
Clock Rise to RD Assertion Delay
2.7
7.0
2.7
7.0
T10
Clock Rise to RD Deassertion Delay
2.4
6.3
2.4
6.3
External I/O Write Timing
Figure 51 and Table 124 diagram the timing for external I/O Writes.
TCLK
X IN
T2
T1
ADDR[23:0]
T3
T4
DATA[7:0]
(output)
T5
T6
CSx
T7
T8
IORQ
T9
T10
WR
Figure 51. External I/O Write Timing
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
210
Table 124. External I/O Write Timing
20 MHz (ns)
Parameter
Description
T1
50 MHz (ns)
Min
Max
Min
Max.
Clock Rise to ADDR Valid Delay
—
7.7
—
7.7
T2
Clock Rise to ADDR Hold Time
2.2
—
2.2
—
T3
Clock Fall to Output DATA Valid Delay
—
6
—
6
T4
Clock Rise to DATA Hold Time
2.3
—
2.3
—
T5
Clock Rise to CSx Assertion Delay
2.6
10.8
2.6
10.8
T6
Clock Rise to CSx Deassertion Delay
2.4
8.8
2.4
8.8
T7
Clock Rise to IORQ Assertion Delay
2.6
7.0
2.6
7.0
T8
Clock Rise to IORQ Deassertion Delay
2.3
6.3
2.3
6.3
T9
Clock Fall to WR Assertion Delay
1.8
4.5
1.8
4.5
T10
Clock Rise to WR Deassertion Delay*
1.6
4.4
1.6
4.4
WR Deassertion to ADDR Hold Time
0.4
—
0.4
—
WR Deassertion to DATA Hold Time
0.5
—
0.5
—
WR Deassertion to CSx Hold Time
1.2
—
1.2
—
WR Deassertion to IORQ Hold Time
0.5
—
0.5
—
Note: *At the conclusion of a Write cycle, deassertion of WR always occurs before any change to ADDR, DATA, CSx,
or IORQ. In certain applications, the deassertion of WR can be concurrent with ADDR, DATA, CSx, or MREQ
when buffering is used off-chip.
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
211
Wait State Timing for Read Operations
Figure 52 illustrates the extension of the memory access signals using a single WAIT state
for a Read operation. This WAIT state is generated by setting CS_WAIT to 001 in the
Chip Select Control Register.
TCLK
TCSx_WAIT
TWAIT
X IN
ADDR[23:0]
DATA[7:0]
(input)
CSx
MREQ
RD
INSTRD
Figure 52. Wait State Timing for Read Operations
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
212
Wait State Timing for Write Operations
Figure 53 illustrates the extension of the memory access signals using a single WAIT state
for a Write operation. This WAIT state is generated by setting CS_WAIT to 001 in the
Chip Select Control Register.
TCLK
TCLK
X IN
ADDR[23:0]
DATA[7:0]
(output)
CSx
MREQ
WR
Figure 53. Wait State Timing for Write Operations
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
213
General Purpose I/O Port Input Sample Timing
Figure 54 illustrates timing of the GPIO input sampling. The input value on a GPIO port
pin is sampled on the rising edge of the system clock. The port value is then available to
the CPU on the second rising clock edge following the change of the port value.
TCLK
System
Clock
Port Value
Changes to 0
GPIO Pin
Input Value
GPIO Input
Data Latch
0 Latched
Into GPIO
Data Register
GPIO Data Register
Value 0 Read
by eZ80
GPIO Data
READ on Data Bus
Figure 54. Port Input Sample Timing
General Purpose I/O Port Output Timing
Figure 55 and Table 125 provide timing information for GPIO port pins.
TCLK
EXTAL
Port Output
T1
T2
Figure 55. GPIO Port Output Timing
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
214
Table 125. GPIO Port Output Timing
20 MHz (ns)
Parameter
Description
T1
T2
50 MHz (ns)
Min
Max
Min
Max
Clock Rise to Port Output Valid Delay
—
9.3
—
9.3
Clock Rise to Port Output Hold Time
2.0
—
2.0
—
External Bus Acknowledge Timing
Table 126 provides information about the external bus acknowledge timing.
Table 126. Bus Acknowledge Timing
20 MHz (ns)
50 MHz (ns)
Parameter
Description
Min
Max
Min
Max
T1
Clock Rise to BUSACK Assertion Delay
2.8
9.3
2.8
9.3
T2
Clock Rise to BUSACK Deassertion Delay
2.5
6.5
2.5
6.5
External System Clock Driver (PHI) Timing
Table 127 lists timing information for the PHI pin. The PHI pin allows external peripherals to synchronize with the internal system clock driver on the ZLP12840 MCU.
Table 127. PHI System Clock Timing
20 MHz (ns)
50 MHz (ns)
Parameter
Description
Min
Max
Min
Max
T1
Clock Rise to PHI Rise
1.6
4.6
1.6
4.6
T2
Clock Fall to PHI Fall
1.8
4.3
1.8
4.3
PS013015-0316
AC Characteristics
eZ80L92 MCU
Product Specification
215
Packaging
Figure 56 illustrates the 100-pin low-profile quad flat pack (LQFP) package for
the eZ80L92 devices.
Figure 56. 100-Lead Plastic Low-Profile Quad Flat Package (LQFP)
PS013015-0316
eZ80L92 MCU
Product Specification
216
Ordering Information
Table 137 lists the product specification index code part number, part number and a brief
description of each ZLP12840 part.
Table 137. Ordering Information
Part
PSI
Description
ZLP12840
eZ80L92AZ020SC,
eZ80L92AZ020SG
100-pin LQFP, 20 MHz, Standard Temperature
ZLP12840
eZ80L92AZ020EC,
eZ80L92AZ020EG
100-pin LQFP, 20 MHz, Extended Temperature
ZLP12840
eZ80L92AZ050SC,
eZ80L92AZ050SG
100-pin LQFP, 50 MHz, Standard Temperature
ZLP12840
eZ80L92AZ050EC,
eZ80L92AZ050EG
100-pin LQFP, 50 MHz, Extended Temperature
For valuable information about customer and technical support as well as hardware and
software development tools, visit the Zilog web site at www.zilog.com. The latest released
version of ZDS can be downloaded from this site.
Part Number Description
Zilog part numbers consist of a number of components, as indicated in the following
example:
Zilog Base Products
PS013015-0316
eZ80
Zilog eZ80® CPU
L92
Product Number
AZ
Package
050
Speed
S or E
Temperature
C or G
Environmental Flow
eZ80L92 MCU
Product Specification
217
Package
AZ = LQFP (also known as VQFP)
Speed
050 = 50 MHz
Standard Temperature
S = 0 ºC to +70 ºC
Extended Temperature
E = –40 ºC to +105 ºC
Environmental Flow
C = Plastic Standard; G = Lead-Free
For example, part number eZ80L92AZ020SC is an eZ80® CPU product in the LQFP
package, operating with a 20 MHz external clock frequency over a 0 ºC to +70 ºC
temperature range, and built using the Plastic Standard environmental flow.
PS013015-0316
eZ80L92 MCU
Product Specification
Index
Numerics
100-pin LQFP package 4, 21
20 MHz Primary Crystal Oscillator Operation 198
32 KHz Real-Time Clock Crystal Oscillator
Operation 199
A
Absolute Maximum Ratings 201
Absolute maximum ratings 201
AC Characteristics 203
ACK 141, 145, 146, 147, 148, 149, 151, 156
Acknowledge 141
ADDR0 5, 21
ADDR1 5, 21
ADDR10 6, 21
ADDR11 7, 21
ADDR12 7, 21
ADDR13 7, 21
ADDR14 7, 21
ADDR15 7, 21
ADDR16 8, 21
ADDR17 8, 21
ADDR18 8, 21
ADDR19 8, 21
ADDR2 5, 21
ADDR20 8, 22
ADDR21 9, 22
ADDR22 9, 22
ADDR23 9, 22
ADDR3 5, 21
ADDR4 5, 21
ADDR5 5, 21
ADDR6 6, 21
ADDR7 6, 21
ADDR8 6, 21
ADDR9 6, 21
PS013015-0316
Address Bus 5, 6, 7, 8, 9
address bus 45, 50, 53, 54, 56, 57, 58, 61, 64, 65,
68, 69, 90, 167, 176, 181
address bus, 24-bit 25
Addressing 151
Arbitration 143
Architectural Overview 1
asynchronous serial data 13, 15, 16
B
Baud Rate Generator 104, 108
Baud Rate Generator Functional Description 133
Block Diagram 3
BRG Control Registers 109
Bus Arbitration Overview 139
Bus Mode Controller 53
Bus Requests During ZDI Debug Mode 167
BUSACK 12, 23, 53, 167, 175, 181, 214
BUSREQ 12, 23, 53, 167, 176, 181
Byte Format 141
C
Characteristics, electrical
Absolute maximum ratings 201
Chip Select Registers 67
Chip Select x Bus Mode Control Register 71
Chip Select x Control Register 70
Chip Select x Lower Bound Register 67
Chip Select x Upper Bound Register 69
Chip Select/Wait State Generator block 5, 6, 7, 8, 9
Chip Selects and Wait States 48
Chip Selects During Bus Request/Bus
Acknowledge Cycles 53
Clear to Send 14, 16, 121
Clock Peripheral Power-Down Registers 35
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
Clock Synchronization 142
Clocking Overview 139
Continuous Mode 79
CPHA 129, 135
CPHA bit 132
CPOL 130, 135
CPOL bit 132
CS0 9, 22, 48, 49, 50, 51
CS1 9, 22, 48, 49, 50, 51
CS2 9, 22, 48, 50, 51
CS3 9, 22, 48, 50, 51
CTS 118, 121
CTS0 14, 125
CTS1 16
Customer Feedback Form 225
DDSR 121
DSR 118, 121
DSR0 14, 125
DSR1 17
DTACK 64, 65
DTR 118, 121
DTR0 14, 125
DTR1 17
E
D
DATA bus 61
Data Bus 10
data bus 53, 56, 57, 58, 65, 71, 90, 167, 176, 181
Data Carrier Detect 15, 17, 121
Data Set Ready 14, 17, 121
Data Terminal Ready 14, 17, 118
Data Transfer Procedure with SPI configured as a
Slave 134
Data Transfer Procedure with SPI Configured as the
Master 133
data transfer, SPI 136
Data Validity 140
DATA0 10, 22
DATA1 10, 22
DATA2 10, 22
DATA3 10, 22
DATA4 10, 22
DATA5 10, 22
DATA6 10, 22
DATA7 10, 22
DC Characteristics 201
DCD 118, 121
DCD0 15, 125
DCD1 17
DCTS 121
DDCD 121
PS013015-0316
Edge-Triggered Interrupts 41
EI, Op Code Map 191
Electrical Characteristics 201
Enabling and Disabling the WDT 74
Event Counter 81
External Bus Acknowledge Timing 214
External I/O Read Timing 208
External I/O Write Timing 209
External Memory Read Timing 205
External Memory Write Timing 206
External System Clock Driver (PHI) Timing 214
eZ80 CPU 33, 34, 51, 53, 57, 58, 64, 65, 123, 169,
183
eZ80 CPU Core 31
eZ80 Product ID Low and High Byte Registers 178
eZ80 Product ID Revision Register 179
eZ80 Webserver-i 1, 4, 5, 10, 11, 12, 20, 25, 33, 34,
38, 44, 45, 48, 50, 73, 77, 80, 107, 109, 151,
158, 161, 162, 163, 165, 166, 169, 172, 173,
176, 177, 178, 179, 182, 186, 201, 203, 214, 216
eZ80 Webserver-i Block Diagram 3
eZ80L92 MCU 3
F
f 21, 22, 54, 57
FAST mode 139, 158
Features 1
Features, eZ80 CPU Core 31
full-duplex transmission 131
Functional Description, Infrared Encoder/Decoder
123
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
G
General Purpose I/O Port Input Sample Timing 213
General Purpose I/O Port Output Timing 213
General-Purpose Input/Output 38
GND 2
GPIO Control Registers 42
GPIO Interrupts 41
GPIO Operation 38
H
HALT 12, 172, 180, 189
HALT instruction 34
HALT Mode 34
HALT mode 1, 35
HALT, Op-Code Map 191
I
I/O Chip Select Operation 50
I/O space 5, 6, 7, 8, 9, 11, 48, 50
I2C Clock Control Register 157
I2C Control Register 153
I2C Data Register 153
I2C General Characteristics 139
I2C Registers 151
I2C Slave Address Register 151
I2C Software Reset Register 159
I2C Status Register 155
IEF1 45, 46, 180
IEF2 45, 46
IM 0, Op Code Map 194
IM 1, Op Code Map 194
IM 2, Op Code Map 194
Infrared Encoder/Decoder 123
Infrared Encoder/Decoder Register 126
Infrared Encoder/Decoder Signal Pins 125
INSTRD 11, 22
Instruction Store 4
0 Registers 176
Intel- 53
Intel Bus Mode 56
Intel Bus Mode (Separate Address and Data Buses)
PS013015-0316
57
internal pull-up 39
Interrupt Controller 44
interrupt enable 12
Interrupt Enable bit 153
interrupt enable bit 89, 106
Interrupt Enable Flag 180
Interrupt Enable flags 47
Interrupt Input 126
interrupt input 13, 14, 15, 16, 17, 18, 19, 20
IORQ 11, 12, 22, 51, 53, 54, 57, 58, 61
IORQ Assertion Delay 208, 210
IORQ Deassertion Delay 208, 210
IORQ Hold Time 210
IrDA 123
IrDA Encoder/Decoder 126
IrDA encoder/decoder 13
IrDA endec 36
IrDA Receive Data 13
IrDA specifications 123
IrDA standard baud rates 123
IrDA transceiver 126
IrDA Transmit Data 13
irq_en 82, 132, 135
irq_en bit 80
J
Jitter, Infrared Encoder/Decoder 125
JTAG Test Mode 12
L
Level-Triggered Interrupts 41
Loopback Testing, Infrared Encoder/Decoder 126
Low-Power Modes 34
M
Maskable Interrupts 44
MASTER mode 130, 139, 154, 156, 157, 158
Master mode 150, 155
master mode 149
Master Mode Start bit 153
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
Master Mode Stop bit 154
MASTER mode, SPI 132
Master Receive 139, 147
Master Transmit 144
MASTER TRANSMIT mode 139
master_en bit 132
Master-In, Slave-Out 129
Master-Out, Slave-In 129
Memory and I/O Chip Selects 48
Memory Chip Select Example 49
Memory Chip Select Operation 48
Memory Chip Select Priority 49
Memory Request 11
memory space 48, 50
MISO 20, 129, 130, 131, 132
Mode Fault 132
mode fault 136
Mode Fault error flag 129
Mode Fault flag 132
Modem status signal 14, 15, 16, 17
MODF 129, 132, 136
MOSI 129, 130, 131, 132
Motorola Bus Mode 63
Motorola-compatible 53
MREQ 11, 12, 22, 48, 53, 54, 57, 58, 61
multimaster conflict 132, 136
open-drain output 139
open-source output 13, 14, 15, 16, 17, 18, 19, 20
Operating Modes 144
Operation of the eZ80 Webserver-i during ZDI
BREAKpoints 166
Ordering Information 216
P
N
NACK 141, 145, 146, 147, 148, 149, 154, 156
New and Improved Instructions, eZ80 CPU Core 31
NMI 12, 22, 31, 35, 47, 73, 74, 75
Nonmaskable Interrupts 47
Not Acknowledge 141
O
OCI Activation 183
OCI Information Requests 185
OCI Interface 184
On-Chip Instrumentation 183
On-Chip Oscillators 198
Op Code maps 191
Open-Drain output 39
PS013015-0316
Packaging 215
Part Number Description 216
PB0 18, 24, 80
PB1 18, 24, 81
PB2 19, 24
PB3 19, 24
PB4 19, 24, 40, 81
PB5 19, 24, 81
PB6 20, 24
PB7 20, 24, 38
PC0 15, 23
PC1 16, 23
PC2 16, 23
PC3 16, 23
PC4 17, 24
PC5 17, 24
PC6 17, 24
PC7 17, 24, 40
PD0 13, 126
PD1 13, 23, 126
PD2 14, 23, 126
PD3 14, 23
PD4 14, 23
PD5 14, 23
PD6 15, 23
PD7 15, 23, 126
Pin Characteristics 21
Pin Description 4
POP, Op Code Map 191, 193, 195
Port x Alternate Register 1 43
Port x Alternate Register 2 43
Port x Data Direction Registers 43
Port x Data Registers 42
Power connections 2
Programmable Reload Timer Operation 77
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
Programmable Reload Timer Registers 82
Programmable Reload Timers 77
pull-up resistor, external 39, 139
PUSH, Op Code Map 191, 193, 195
R
RD 11, 22, 48, 51, 53, 57, 58, 61
RD Assertion Delay 209
RD Deassertion Delay 209
Reading the Current Count Value 80
Real-Time Clock 88
Real-Time Clock Alarm 88
Real-Time Clock Alarm Control Register 102
Real-Time Clock Alarm Day-of-the-Week Register
101
Real-Time Clock Alarm Hours Register 100
Real-Time Clock Alarm Minutes Register 99
Real-Time Clock Alarm Seconds Register 98
Real-Time Clock Battery Backup 89
Real-Time Clock Century Register 97
Real-Time Clock Control Register 102
Real-Time Clock Day-of-the-Month Register 94
Real-Time Clock Day-of-the-Week Register 93
Real-Time Clock Hours Register 92
Real-Time Clock Minutes Register 91
Real-Time Clock Month Register 95
Real-Time Clock Oscillator and Source Selection
89
Real-Time Clock Recommended Operation 89
Real-Time Clock Registers 90
Real-Time Clock Seconds Register 90
Real-Time Clock Year Register 96
Receive, Infrared Encoder/Decoder 124
Recommended Usage of the Baud Rate Generator
109
Register Map 25
Request to Send 14, 16, 118
RESET 11, 22, 34, 35, 39, 48, 73, 74, 75, 89, 90,
102, 109, 126, 133, 134, 171, 172, 183, 184
Reset 33
RESET event 38
RESET Operation 33
RESET Or NMI Generation 74
PS013015-0316
Reset States 49
Resetting the I2C Registers 151
RI 106, 118, 121
RI0 15, 125
RI1 17, 40
Ring Indicator 15, 17, 121
RTS 118, 121, 125
RTS0 14
RTS1 16
RxD0 13
RxD1 16
S
Schmitt Trigger 11
SCK 19, 129, 130
SCK Idle State 131
SCK pin 132, 136
SCK Receive Edge 131
SCK signal 132
SCK Transmit Edge 131
SCL 20, 24, 139, 140, 141, 157
SCL line 142, 143, 144
SDA 20, 24, 139, 140, 141, 143, 150
serial bus, SPI 137
Serial Clock 130, 139
Serial Clock, I2C 20
Serial Clock, SPI 19, 129
Serial Data 139
serial data 129
Serial Data, I2C 20
Serial Peripheral Interface 128
Setting Timer Duration 77
Single Pass Mode 78
SLA 146, 148, 152, 190
SLA, Op Code Map 196, 197
SLA, Op Code map 192
SLAVE mode 139, 154, 156
slave mode 150, 151, 152
SLAVE mode, SPI 132
Slave Receive 139, 150
Slave Select 129
Slave Transmit 139, 149
SLEEP Mode 34
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
SPI 1, 36, 44, 128, 129, 132
SPI Baud Rate Generator 133
SPI Baud Rate Generator Register 27
SPI Baud Rate Generator Registers—Low Byte and
High Byte 134
SPI Block 27
SPI Control Register 27, 135
SPI Data Rate 133
SPI Flags 132
SPI Functional Description 131
SPI interrupt service routine 44
SPI Master device 134
SPI master device 20
SPI MASTER mode 132
SPI mode 19
SPI Receive Buffer Register 27, 137
SPI Registers 134
SPI serial bus 137
SPI Serial Clock 19
SPI Signals 129
SPI slave device 20
SPI SLAVE mode 132
SPI Status Register 27, 136
SPI Status register 132
SPI Transmit Shift Register 27, 134, 137
SPI Transmit Shift register 133
SPIF 131
spiF 136
SPIF bit 137
SPIF flag 132
SPIF status bit 137
SRA 190
SRA, Op Code Map 192, 196
SS 19, 129, 131, 132, 133, 136
STA 153
standard mode 139
START and STOP Conditions 140
Supply Voltage 202
supply voltage 1, 39, 139, 201
Switching Between Bus Modes 67
system clock cycles 11, 51, 53, 54, 58, 62, 74, 183
System Clock Oscillator Input 18
System Clock Oscillator Output 18
PS013015-0316
T
TERI 121
Test Mode 184
Time-Out Period Selection 74
Timer Control Register 82
Timer Data Register—High Byte 84
Timer Data Register—Low Byte 83
Timer Input Source Select Register 86
Timer Input Source Selection 80
Timer Output 81
Timer Reload Register—High Byte 86
Transferring Data 141
Transmit, Infrared Encoder/Decoder 124
TxD0 13
TxD1 15
U
UART Baud Rate Generator Register —Low and
High Bytes 109
UART FIFO Control Register 114
UART Functional Description 105
UART Interrupt Enable Register 112
UART Interrupt Identification Register 113
UART Interrupts 106
UART Line Control Register 115
UART Line Status Register 118
UART Modem Control 106
UART Modem Control Register 117
UART Modem Status Interrupt 107
UART Modem Status Register 120
UART Receive Buffer Register 111
UART Receiver 105
UART Receiver Interrupts 106
UART Recommended Usage 107
UART Registers 110
UART Scratch Pad Register 122
UART Transmit Holding Register 111
UART Transmitter 105
UART Transmitter Interrupt 106
Universal Asynchronous Receiver/Transmitter 104
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
V
VCC 2
W
WAIT 1, 11, 22, 58, 61, 64, 65
WAIT Input Signal 51
WAIT pin, external 53, 54
WAIT state 54, 62, 211, 212
Wait State Timing for Read Operations 211
Wait State Timing for Write Operations 212
WAIT states 45, 58, 61, 70, 167
Wait States 51
Watch-Dog Timer 73
Watch-Dog Timer Control Register 75
Watch-Dog Timer Operation 74
Watch-Dog Timer Registers 75
Watch-Dog Timer Reset Register 76
WCOL 132, 133
wcOl 136
WR 11, 22, 48, 51, 54, 58, 61, 210
Write Collision 133
write collision 132
write collision, SPI 136
ZDI Read-Only Registers 169
ZDI Register Addressing 163
ZDI Register Definitions 169
ZDI Single-Byte Read 165
ZDI SINGLE-BYTE WRITE 164
ZDI Start Condition 162
ZDI Status Register 179
ZDI Write Data Registers 173
ZDI Write Memory Register 177
ZDI Write Operations 164
ZDI Write-Only Registers 168
ZDI_BUS_STAT 167, 169, 181
ZDI_BUSACK_EN 167
ZDI_BUSAcK_En 181
ZDI-Supported Protocol 161
Zilog Debug Interface 160
Z
Z80- 53
Z80 Bus Mode 53
ZCL 162, 164, 171
ZDA 162, 171, 184
ZDI Address Match Registers 169
ZDI Block Read 166
ZDI BLOCK WRITE 165
ZDI BREAK Control Register 170
ZDI Bus Control Register 175
ZDI Bus Status Register 181
ZDI Clock and Data Conventions 162
ZDI Master Control Register 172
ZDI Read Memory Register 182
ZDI Read Operations 165
ZDI Read Register Low, High, and Upper 180
ZDI Read/Write Control Register 173
PS013015-0316
PRELIMINARY
Index
eZ80L92 MCU
Product Specification
225
Customer Support
For answers to technical questions about the product, documentation, or any other issues
with Zilog’s offerings, please visit Zilog’s
Knowledge Base at http://www.zilog.com/kb.
For any comments, detail technical questions, or reporting problems, please visit Zilog’s
Technical Support at http://support.zilog.com.
PS013015-0316
Customer Support
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