KSZ8842-16M/-32M
Two-Port Ethernet Switch with Non-PCI Interface
Features
• Non-Blocking Switch Fabric Assures Fast Packet
Delivery by Utilizing a 1K Entry Forwarding Table
and a Store-and-Forward Architecture
• Fully Compliant with IEEE 802.3u Standards
• Full-Duplex IEEE 802.3x Flow Control (Pause)
with Force Mode Option
• Half-Duplex Back Pressure Flow Control
• Per Port-Based, Software Power-Save on PHY
(Idle Link Detection, Register Configuration Preserved)
• Single Power Supply: 3.3V
• Commercial Temperature Range: 0°C to +70°C
• Industrial Temperature Range: –40°C to +85°C
• Available in 128-pin PQFP, 100-ball LFBGA, and
128-pin LQFP
• Available in -16 Version for 8/16-Bit Bus Support
and -32 version for 32-Bit Bus Support
Advanced Switch Management
Additional Features
• IEEE 802.1Q VLAN Support for Up to 16 Groups
(Full Range of VLAN IDs)
• VLAN ID Tag/Untag Options, on a Per Port Basis
• IEEE 802.1p/Q Tag Insertion or Removal on a Per
Port Basis (Egress)
• Programmable Rate Limiting at the Ingress and
Egress Ports
• Broadcast Storm Protection
• IEEE 802.1d Spanning Tree Protocol Support
• MAC Filtering Function to Filter or Forward
Unknown Unicast Packets
• Direct Forwarding Mode Enabling the Processor
to Identify the Ingress Port and to Specify the
Egress Port
• Internet Group Management Protocol (IGMP) v1/
v2 Snooping Support for Multicast Packet Filtering
• IPV6 Multicast Listener Discovery (MLD) Snooping Support
In Addition to Offering All of the Features of an Integrated Layer-2 Managed Switch, the KSZ8842M
Offers:
Switch Management
Monitoring
• Port Mirroring/Monitoring/Sniffing: Ingress and/or
Egress Traffic to Any Port
• MIB Counters for Fully Compliant Statistics Gathering - 34 MIB Counters Per Port
• Loopback Modes for Remote Failure Diagnostics
Comprehensive Register Access
• Control Registers Configurable On-the-Fly (PortPriority, 802.1p/d/Q)
QoS/CoS Packets Prioritization Support
• Per Port, 802.1p and DiffServ-Based
• Remapping of 802.1p Priority Field on a Per Port
Basis
• Repeater Mode Capabilities to Allow for Cut
Through in Latency Critical Industrial Ethernet or
Embedded Ethernet Applications
• Dynamic Buffer Memory Scheme
- Essential for Applications Such as Video over
IP where Image Jitter is Unacceptable
• 2-Port Switch with a Flexible 8-Bit, 16-Bit, or 32Bit Generic Host Processor Interfaces
• Microchip LinkMD® Cable Diagnostic to Determine Cable Length, Diagnose Faulty Cables, and
Determine Distance to Fault
• Hewlett Packard (HP) Auto-MDIX Crossover with
Disable and Enable Options
• Four Priority Queues to Handle Voice, Video,
Data, and Control Packets
• Ability to Transmit and Receive Frames up to
1916 bytes
Applications
•
•
•
•
•
•
•
•
Video Distribution Systems
High-End Cable, Satellite, and IP Set-Top Boxes
Video over IP
Voice over IP (VoIP) and Analog Telephone
Adapters (ATA)
Industrial Control in Latency Critical Applications
Motion Control
Industrial Control Sensor Devices (Temperature,
Pressure, Levels, and Valves)
Security and Surveillance Cameras
Power Modes, Packaging, and Power Supplies
Markets
• Full-Chip Hardware Power-Down (Register Configuration not Saved) Allows Low Power Dissipation
• Fast Ethernet
• Embedded Ethernet
• Industrial Ethernet
2020 Microchip Technology Inc.
DS00003459A-page 1
KSZ8842-16M/-32M
TO OUR VALUED CUSTOMERS
It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip
products. To this end, we will continue to improve our publications to better suit your needs. Our publications will be refined and
enhanced as new volumes and updates are introduced.
If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via
E-mail at docerrors@microchip.com. We welcome your feedback.
Most Current Data Sheet
To obtain the most up-to-date version of this data sheet, please register at our Worldwide Web site at:
http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page.
The last character of the literature number is the version number, (e.g., DS30000000A is version A of document DS30000000).
Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the
revision of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
• Microchip’s Worldwide Web site; http://www.microchip.com
• Your local Microchip sales office (see last page)
When contacting a sales office, please specify which device, revision of silicon and data sheet (include -literature number) you are
using.
Customer Notification System
Register on our web site at www.microchip.com to receive the most current information on all of our products.
DS00003459A-page 2
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Table of Contents
1.0 Introduction ..................................................................................................................................................................................... 4
2.0 Pin Description and Configuration ................................................................................................................................................... 5
3.0 Functional Description .................................................................................................................................................................. 23
4.0 Register Descriptions .................................................................................................................................................................... 46
5.0 Operational Characteristics ......................................................................................................................................................... 109
6.0 Electrical Characteristics ............................................................................................................................................................. 110
7.0 Timing Specifications .................................................................................................................................................................. 111
8.0 Selection of Isolation Transformers ............................................................................................................................................. 122
9.0 Package Outline .......................................................................................................................................................................... 123
Appendix A: Data Sheet Revision History ......................................................................................................................................... 127
The Microchip Web Site .................................................................................................................................................................... 128
Customer Change Notification Service ............................................................................................................................................. 128
Customer Support ............................................................................................................................................................................. 128
Product Identification System ........................................................................................................................................................... 129
2020 Microchip Technology Inc.
DS00003459A-page 3
KSZ8842-16M/-32M
1.0
INTRODUCTION
1.1
General Description
The KSZ8842-series of 2-port switches includes PCI and non-PCI CPU interfaces, and are available in 8-/16-bit and 32bit bus designs. This data sheet describes the KSZ8842M-series of non-PCI CPU interface chips. For information on
the KSZ8842 PCI CPU interface switches, refer to the KSZ8842P data sheet.
The KSZ8842M is the industry’s first fully managed, 2-port switch with a non-PCI CPU interface. It is based on a proven,
4th generation, integrated Layer-2 switch, compliant with IEEE 802.3u standards. Also an industrial temperature grade
version of the KSZ8842, the KSZ8842MVLI, can be ordered.
The KSZ8842M can be configured as a switch or as a low-latency (≤310 nanoseconds) repeater in latency-critical,
embedded or industrial Ethernet applications. For industrial applications, the KSZ8842M can run in half-duplex mode
regardless of the application.
The KSZ8842M offers an extensive feature set that includes tag/port-based VLAN, quality of service (QoS) priority management, management information base (MIB) counters, and CPU control/data interfaces to effectively address Fast
Ethernet applications.
The KSZ8842M contains two 10/100 transceivers with patented, mixed-signal, low-power technology, two media access
control (MAC) units, a direct memory access (DMA) channel, a high-speed, non-blocking, switch fabric, a dedicated 1K
entry forwarding table, and an on-chip frame buffer memory.
FIGURE 1-1:
SYSTEM BLOCK DIAGRAM
1K Look-Up
Engine
10/100
T/TX
PHY 1
10/100
MAC 1
HP Auto
MDI/MDI-X
10/100
T/TX
PHY 2
10/100
MAC 2
10/100
MAC 3
Embedded
Processor Interface
Non-PCI
CPU
Bus Interface Unit
8/16/32 Bit
Generic Host Interface
FIFO, Flow Control, VLAN Tagging ,Priority
HP Auto
MDI/MDI-X
Queue
Management
Buffer
Management
Frame
Buffers
MIB
Counters
Control
Registers
EEPROM
Interface
EEPROM I/F
P1 LED[2:0]
P2 LED[2:0]
DS00003459A-page 4
LED
Drivers
Strap In
Configuration Pins
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
2.0
PIN DESCRIPTION AND CONFIGURATION
PIN CONFIGURATION FOR KSZ8842-16MQL
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
KSZ8842-16MQL
(Top View)
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
AGND
VDDAP
AGND
ISET
NC
NC
AGND
VDDA
TXP2
TXM2
AGND
RXP2
RXM2
VDDARX
VDDATX
TXM1
TXP1
AGND
RXM1
RXP1
NC
VDDA
AGND
NC
NC
AGND
TESTEN
SCANEN
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
DGND
VDDIO
RDYRTNN
BCLK
NC
NC
SRDYN
INTRN
LDEVN
RDN
EECS
ARDY
CYCLEN
P2LED3
DGND
VDDCO
VLBUSN
EEEN
P1LED3
EEDO
EESK
EEDI
SWR
AEN
WRN
DGND
ADSN
PWRDN
AGND
VDDA
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
26
27
28
29
30
31
32
33
34
35
36
37
38
NC
NC
NC
NC
DGND
VDDIO
NC
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
DGND
DGND
VDDIO
D2
D1
D0
102
101
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
75
74
73
72
71
70
69
68
67
66
65
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
VDDIO
VDDC
DGND
NC
BE0N
BE1N
NC
NC
A1
A2
A3
A4
A5
VDDIO
DGND
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
RSTN
X2
X1
FIGURE 2-1:
2020 Microchip Technology Inc.
DS00003459A-page 5
KSZ8842-16M/-32M
PIN CONFIGURATION FOR KSZ8842-16MVL
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
NC
NC
NC
NC
VDDIO
VDDC
DGND
NC
BE0N
BE1N
NC
NC
A1
A2
A3
A4
A5
VDDIO
DGND
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
RSTN
X2
X1
FIGURE 2-2:
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
KSZ8842-16MVL
(Top View)
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
AGND
VDDAP
AGND
ISET
NC
NC
AGND
VDDA
TXP2
TXM2
AGND
RXP2
RXM2
VDDARX
VDDATX
TXM1
TXP1
AGND
RXM1
RXP1
NC
VDDA
AGND
NC
NC
AGND
VDDA
AGND
PWRDN
ADSN
DGND
WRN
TESTEN
SCANEN
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
DGND
VDDIO
RDYRTNN
BCLK
NC
NC
SRDYN
INTRN
LDEVN
RDN
EECS
ARDY
CYCLEN
P2LED3
DGND
VDDCO
VLBUSN
EEEN
P1LED3
EEDO
EESK
EEDI
SWR
AEN
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
26
27
28
29
30
31
32
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
DGND
VDDIO
NC
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
DGND
DGND
VDDIO
D2
D1
D0
DS00003459A-page 6
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-1:
PIN DESCRIPTION FOR KSZ8842-16MQL/MVL (8-/16-BIT)
Pin
Number
Pin Name
Type
1
TEST_EN
I
Test Enable
For normal operation, pull-down this pin to ground.
2
SCAN_EN
I
Scan Test Scan Mux Enable
For normal operation, pull-down this pin to ground.
Description
Port 1 and Port 2 LED Indicators, defined as follows
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0, 0] Default
[0, 1]
P1LED3/P2LED3
—
—
P1LED2/P2LED2
Link/Activity
100Link/Activity
P1LED1/P2LED1
Full-Duplex/Col
10Link/Activity
P1LED0/P2LED0
Speed
Full-Duplex
Reg. SGCR5 bit [15,9]
3
4
5
6
7
8
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
OPU
[1, 0]
[1, 1]
P1LED3/P2LED3
Activity
—
P1LED2/P2LED2
Link
—
P1LED1/P2LED1
Full-Duplex/Col
—
P1LED0/P2LED0
Speed
—
Note:
Link = On; Activity = Blink; Link/Act = On/Blink; Full-Duplex/
Col = On/Blink; Full-Duplex = On (Full-duplex); Off (Halfduplex); Speed = On (100BASE-T); Off (10BASE-T)
Note:
P1LED3 is pin 27. P2LED3 is pin 22.
Port 1 and Port 2 LED indicators for Repeater mode defined as follows:
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0,0] Default
[0,1] [1,0] [1,1]
P1LED3/P2LED3
RPT_COL, RPT_ACT
—
P1LED2/P2LED2
RPT_Link3/RX,
RPT_ERR3
—
P1LED1/P2LED1
RPT_Link2/RX,
RPT_ERR2
—
P1LED0/P2LED0
RPT_Link1/RX,
RPT_ERR1
—
Note:
RPT_COL = Blink; RPT_Link3/RX (Host port) = On/Blink;
RPT_Link2/RX (Port 2) = On/Blink; RPT_Link1/RX (Port 1) =
On/Blink; RPT_ACT = on if any activity, RPT_ERR3/2/1 = RX
error on port 3, 2, or 1.
9
DGND
GND
10
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
IPD
Ready Return Not:
For VLBus-like mode: Asserted by the host to complete synchronous
read cycles. If the host doesn’t connect to this pin, assert this pin.
For burst mode (32-bit interface only): Host drives this pin low to signal
waiting states.
11
RDYRTNN
2020 Microchip Technology Inc.
Digital ground.
DS00003459A-page 7
KSZ8842-16M/-32M
TABLE 2-1:
Pin
Number
PIN DESCRIPTION FOR KSZ8842-16MQL/MVL (8-/16-BIT) (CONTINUED)
Pin Name
Type
Description
IPD
Bus Interface Clock
Local bus clock for synchronous bus systems. Maximum frequency is
50 MHz.
This pin should be tied Low or unconnected if it is in asynchronous
mode.
NC
IPU
No connect.
NC
OPU
No connect.
12
BCLK
13
14
15
SRDYN
OPU
Synchronous Ready Not
Ready signal to interface with synchronous bus for both EISA-like and
VLBus-like extend accesses.
For VLBus-like mode, the falling edge of this signal indicates ready. This
signal is synchronous to the bus clock signal BCLK.
For burst mode (32-bit interface only), the KSZ8842M drives this pin low
to signal wait states.
16
INTRN
OPD
Interrupt
Active Low signal to host CPU to indicate an interrupt status bit is set,
this pin needs an external 4.7 kΩ pull-up resistor.
17
LDEVN
OPD
Local Device Not
Active Low output signal, asserted when AEN is Low and A15-A4
decode to the KSZ8842M address programmed into the high byte of the
base address register. LDEVN is a combinational decode of the Address
and AEN signal.
18
RDN
IPD
Read Strobe Not
Asynchronous read strobe, active-low.
19
EECS
OPU
EEPROM Chip Select
OPD
Asynchronous Ready
ARDY may be used when interfacing asynchronous buses to extend bus
access cycles. It is asynchronous to the host CPU or bus clock. This pin
needs an external 4.7 kΩ pull-up resistor.
20
ARDY
21
CYCLEN
IPD
Cycle Not
For VLBus-like mode cycle signal; this pin follows the addressing cycle
to signal the command cycle.
For burst mode (32-bit interface only), this pin stays High for read cycles
and Low for write cycles.
22
P2LED3
OPD
Port 2 LED indicator
See the description in pins 6, 7, and 8.
23
DGND
GND
Digital IO ground.
24
VDDCO
P
1.2V digital core voltage output (internal 1.2V LDO power supply output),
this 1.2V output pin provides power to VDDC, VDDA and VDDAP pins.
Note: Internally generated power voltage. Do not connect an external
power supply to this pin. This pin is used for connecting external filter
(Ferrite bead and capacitors). It is recommended this pin should be connected to 3.3V power rail by a 100Ω resistor for the internal LDO application.
25
VLBUSN
IPD
VLBus-like Mode
Pull-down or float: Bus interface is configured for synchronous mode.
Pull-up: Bus interface is configured for 8-bit or 16-bit asynchronous
mode or EISA-like burst mode.
26
EEEN
IPD
EEPROM Enable
EEPROM is enabled and connected when this pin is pulled up.
EEPROM is disabled when this pin is pulled down or no connect.
DS00003459A-page 8
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-1:
PIN DESCRIPTION FOR KSZ8842-16MQL/MVL (8-/16-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
27
P1LED3
OPD
Port 1 LED indicator
See the description in pins 3, 4, and 5.
28
EEDO
OPD
EEPROM Data Out
This pin is connected to DI input of the serial EEPROM.
OPD
EEPROM Serial Clock
A 4 μs (OBCR[1:0] = 11 on-chip bus speed @ 25 MHz) or 800 ns
(OBCR[1:0] = 00 on-chip bus speed @ 125 MHz) serial output clock
cycle to load configuration data from the serial EEPROM.
29
EESK
Description
30
EEDI
IPD
EEPROM Data In
This pin is connected to DO output of the serial EEPROM when EEEN is
pull-up.
This pin can be pull-down for 8-bit bus mode, pull-up for 16-bit bus mode
or don’t care for 32-bit bus mode when EEEN is pull-down (without
EEPROM).
31
SWR
IPD
Synchronous Write/Read
Write/Read signal for synchronous bus accesses. Write cycles when
high and Read cycles when low.
32
AEN
IPU
Address Enable
Address qualifier for the address decoding, active-low.
33
WRN
IPD
Write Strobe Not
Asynchronous write strobe, active-low.
34
DGND
GND
Digital IO ground
35
ADSN
IPD
Address Strobe Not
For systems that require address latching, the rising edge of ADSN indicates the latching moment of A15-A1 and AEN.
36
PWRDN
IPU
Full-chip power-down.
(Low = Power down; High or floating = Normal operation).
37
AGND
GND
Analog ground
38
VDDA
P
39
AGND
GND
40
NC
—
No Connect
No Connect
1.2V analog VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
Analog ground
41
NC
—
42
AGND
GND
43
VDDA
P
1.2V analog VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
Analog ground
44
NC
—
No Connect
45
RXP1
I/O
Port 1 physical receive (MDI) or transmit signal (+ differential)
Port 1 physical receive (MDI) or transmit signal (– differential)
46
RXM1
I/O
47
AGND
GND
48
TXP1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (+ differential)
49
TXM1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (– differential)
50
VDDATX
P
3.3V analog VDD input power supply with well decoupling capacitors.
51
VDDARX
P
3.3V analog VDD input power supply with well decoupling capacitors.
52
RXM2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (– differential)
53
RXP2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (+ differential)
54
AGND
GND
55
TXM2
I/O
2020 Microchip Technology Inc.
Analog ground
Analog ground
Port 2 physical receive (MDI) or transmit (MDIX) signal (– differential)
DS00003459A-page 9
KSZ8842-16M/-32M
TABLE 2-1:
PIN DESCRIPTION FOR KSZ8842-16MQL/MVL (8-/16-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
56
TXP2
I/O
57
VDDA
P
58
AGND
GND
Analog ground
59
NC
IPU
No connect
60
NC
IPU
No connect
61
ISET
O
62
AGND
GND
63
VDDAP
P
64
AGND
GND
65
X1
I
66
X2
O
67
RSTN
IPU
68
A15
I
Address 15
69
A14
I
Address 14
70
A13
I
Address 13
71
A12
I
Address 12
72
A11
I
Address 11
73
A10
I
Address 10
74
A9
I
Address 9
75
A8
I
Address 8
76
A7
I
Address 7
77
A6
I
Address 6
78
DGND
GND
79
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
80
A5
I
Address 5
81
A4
I
Address 4
82
A3
I
Address 3
83
A2
I
Address 2
84
A1
I
Address 1
85
NC
I
No Connect
86
NC
I
No Connect
87
BE1N
I
Byte Enable 1 Not, Active-low for Data byte 1 enable (don’t care in 8-bit
bus mode).
88
BE0N
I
Byte Enable 0 Not, Active-low for Data byte 0 enable (there is an internal
inverter enabled and connected to the BE1N for 8-bit bus mode).
No Connect
89
NC
I
90
DGND
GND
91
VDDC
P
DS00003459A-page 10
Description
Port 2 physical receive (MDI) or transmit (MDIX) signal (+ differential)
1.2 analog VDD input power supply from VDDCO (pin 24) through external Ferrite bead and capacitor.
Set physical transmits output current.
Pull down this pin with a 3.01 kΩ 1% resistor to ground.
Analog ground
1.2V analog VDD for PLL input power supply from VDDCO (pin 24)
through external Ferrite bead and capacitor.
Analog ground
25 MHz crystal or oscillator clock connection.
Pins (X1, X2) connect to a crystal. If an oscillator is used, X1 connects to
a 3.3V tolerant oscillator and X2 is a no connect.
Note: Clock requirement is ±50 ppm for either crystal or oscillator.
Hardware reset pin (active-low). This reset input is required minimum of
10 ms low after stable supply voltage 3.3V.
Digital IO ground
Digital core ground
1.2V digital core VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-1:
PIN DESCRIPTION FOR KSZ8842-16MQL/MVL (8-/16-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
Description
92
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
93
NC
I
No Connect
94
NC
I
No Connect
95
NC
I
No Connect
96
NC
I
No Connect
97
NC
I
No Connect
98
NC
I
No Connect
99
NC
I
No Connect
100
NC
I
No Connect
101
NC
I
No Connect
102
NC
I
No Connect
103
NC
I
No Connect
104
NC
I
No Connect
105
NC
I
No Connect
No Connect
106
NC
I
107
DGND
GND
108
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
109
NC
I
No Connect
110
D15
I/O
Data 15
111
D14
I/O
Data 14
112
D13
I/O
Data 13
113
D12
I/O
Data 12
114
D11
I/O
Data 11
115
D10
I/O
Data 10
116
D9
I/O
Data 9
117
D8
I/O
Data 8
118
D7
I/O
Data 7
119
D6
I/O
Data 6
120
D5
I/O
Data 5
121
D4
I/O
Data 4
Data 3
Digital IO ground
122
D3
I/O
123
DGND
GND
Digital IO ground
124
DGND
GND
Digital core ground
125
VDDIO
P
126
D2
I/O
Data 2
127
D1
I/O
Data 1
128
D0
I/O
Data 0
Note 2-1
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
P = power supply; GND = ground; I = input; O = output
I/O = bi-directional; IPU/O = Input with internal pull-up during reset; output pin otherwise.
IPU = Input with internal pull-up; IPD = Input with internal pull-down.
OPU = Output with internal pull-up; OPD = Output with internal pull-down.
2020 Microchip Technology Inc.
DS00003459A-page 11
KSZ8842-16M/-32M
FIGURE 2-3:
PIN CONFIGURATION FOR KSZ8842-16MBL
KSZ8842-16MBL (Top View)
DS00003459A-page 12
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-2:
BALL DESCRIPTION FOR KSZ8842-16MBL (8-/16-BIT)
Ball
Number
Ball Name
Type
E8
TEST_EN
I
Test Enable
For normal operation, pull down this ball to ground.
D10
SCAN_EN
I
Scan Test Scan Mux Enable
For normal operation, pull down this ball to ground.
Function
Port 1 and Port 2 LED indicators are defined as follows:
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0,0] Default
[0,1]
P1LED3/P2LED3
—
—
P1LED2/P2LED2
Link/Activity
100Link/Activity
P1LED1/P2LED1
Full-Duplex/Col
10Link/Activity
P1LED0/P2LED0
Speed
Full-Duplex
Reg. SGCR5 bit [15,9]
A10
B10
C10
A9
B9
C9
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
[1,0]
[1,1]
P1LED3/P2LED3
Activity
—
P1LED2/P2LED2
Link
—
P1LED1/P2LED1
Full-Duplex/Col
—
P1LED0/P2LED0
Speed
—
Note:
Link = On; Activity = Blink; Link/Act = On/Blink; Full-Duplex/
Col = On/Blink; Full-Duplex = On (Full-duplex); Off (Halfduplex); Speed = On (100BASE-T); Off (10BASE-T)
Note:
P1LED3 is ball A4. P2LED3 is ball C6.
OPU
Port 1 and Port 2 LED indicators for Repeater mode are defined as follows:
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0,0] Default
[0,1] [1,0] [1,1]
P1LED3/P2LED3
RPT_COL, RPT_ACT
—
P1LED2/P2LED2
RPT_Link3/RX,
RPT_ERR3
—
P1LED1/P2LED1
RPT_Link2/RX,
RPT_ERR2
—
P1LED0/P2LED0
RPT_Link1/RX,
RPT_ERR1
—
Note:
D9
RDYRTNN
2020 Microchip Technology Inc.
IPD
RPT_COL = Blink; RPT_Link3/RX (Host port) = On/Blink;
RPT_Link2/RX (Port 2) = On/Blink; RPT_Link1/RX (Port 1) =
On/Blink; RPT_ACT = on if any activity, RPT_ERR3/2/1 = RX
error on port 3, 2, or 1.
Ready Return Not:
For VLBus-like mode: Asserted by the host to complete synchronous
read cycles. If the host doesn’t connect to this ball, assert this ball.
For burst mode (32-bit interface only): Host drives this ball low to signal
waiting states.
DS00003459A-page 13
KSZ8842-16M/-32M
TABLE 2-2:
Ball
Number
A8
BALL DESCRIPTION FOR KSZ8842-16MBL (8-/16-BIT) (CONTINUED)
Ball Name
BCLK
Type
Function
IPD
Bus Interface Clock
Local bus clock for synchronous bus systems. Maximum frequency is
50 MHz.
This ball should be tied Low or unconnected if it is in asynchronous
mode.
B8
SRDYN
OPU
Synchronous Ready Not
Ready signal to interface with synchronous bus for both EISA-like and
VLBus-like extend accesses.
For VLBus-like mode, the falling edge of this signal indicates ready. This
signal is synchronous to the bus clock signal BCLK.
For burst mode (32-bit interface only), the KSZ8842M drives this ball low
to signal wait states.
C8
INTRN
OPD
Interrupt
Active Low signal to host CPU to indicate an interrupt status bit is set,
this ball needs an external 4.7 kΩ pull-up resistor.
A7
LDEVN
OPD
Local Device Not
Active Low output signal, asserted when AEN is Low and A15-A4
decode to the KSZ8842M address programmed into the high byte of the
base address register. LDEVN is a combinational decode of the Address
and AEN signal.
B7
RDN
IPD
Read Strobe Not
Asynchronous read strobe, active Low.
C7
EECS
OPU
EEPROM Chip Select
OPD
Asynchronous Ready
ARDY may be used when interfacing asynchronous buses to extend bus
access cycles. It is asynchronous to the host CPU or bus clock. This ball
needs an external 4.7 kΩ pull-up resistor.
A6
ARDY
B6
CYCLEN
IPD
Cycle Not
For VLBus-like mode cycle signal; this ball follows the addressing cycle
to signal the command cycle.
For burst mode (32-bit interface only), this ball stays High for read cycles
and Low for write cycles.
C6
P2LED3
OPD
Port 2 LED indicator
See the description in balls A9, B9, and C9.
A5
VLBUSN
IPD
VLBus-like Mode
Pull-down or float: Bus interface is configured for synchronous mode.
Pull-up: Bus interface is configured for 8-bit or 16-bit asynchronous
mode or EISA-like burst mode.
B5
EEEN
IPD
EEPROM Enable
EEPROM is enabled and connected when this ball is pulled up.
EEPROM is disabled when this ball is pulled down or no connect.
A4
P1LED3
OPD
Port 1 LED indicator
See the description in balls A10, B10, and C10.
B4
EEDO
OPD
EEPROM Data Out
This ball is connected to DI input of the serial EEPROM.
OPD
EEPROM Serial Clock
A 4 μs (OBCR[1:0] = 11 on-chip bus speed @ 25 MHz) or 800 ns
(OBCR[1:0] = 00 on-chip bus speed @ 125 MHz) serial output clock
cycle to load configuration data from the serial EEPROM.
A3
EESK
DS00003459A-page 14
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-2:
Ball
Number
BALL DESCRIPTION FOR KSZ8842-16MBL (8-/16-BIT) (CONTINUED)
Ball Name
Type
Function
B3
EEDI
IPD
EEPROM Data In
This ball is connected to DO output of the serial EEPROM when EEEN
is pulled up.
This ball can be pulled down for 8-bit bus mode, pulled up for 16-bit bus
mode or don’t care for 32-bit bus mode when EEEN is pulled down (without EEPROM).
C3
SWR
IPD
Synchronous Write/Read
Write/Read signal for synchronous bus accesses. Write cycles when
high and Read cycles when low.
A2
AEN
IPU
Address Enable
Address qualifier for the address decoding, active Low.
B2
WRN
IPD
Write Strobe Not
Asynchronous write strobe, active Low.
A1
ADSN
IPD
Address Strobe Not
For systems that require address latching, the rising edge of ADSN indicates the latching moment of A15-A1 and AEN.
B1
PWRDN
IPU
Full-chip power-down. Low = Power down; High or floating = Normal
operation.
C1
RXP1
I/O
Port 1 physical receive (MDI) or transmit (MDIX) signal (+ differential)
C2
RXM1
I/O
Port 1 physical receive (MDI) or transmit (MDIX) signal (– differential)
D1
TXP1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (+ differential)
D2
TXM1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (– differential)
F2
RXM2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (– differential)
F1
RXP2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (+ differential)
G2
TXM2
I/O
Port 2 physical transmit (MDI) or receive (MDIX) signal (– differential)
G1
TXP2
I/O
Port 2 physical transmit (MDI) or receive (MDIX) signal (+ differential)
H2
TEST2
IPU
Test input 2
For normal operation, leave this ball open.
G3
ISET
O
J1
X1
I
K1
X2
O
J2
RSTN
IPU
K2
A15
I
Address 15
K3
A14
I
Address 14
J3
A13
I
Address 13
H3
A12
I
Address 12
K4
A11
I
Address 11
J4
A10
I
Address 10
H4
A9
I
Address 9
K5
A8
I
Address 8
Set physical transmits output current.
Pull-down this ball with a 3.01 kΩ 1% resistor to ground.
25 MHz crystal or oscillator clock connection.
Balls (X1, X2) connect to a crystal. If an oscillator is used, X1 connects
to a 3.3V tolerant oscillator and X2 is a no connect.
Note: Clock requirement is ±50 ppm for either crystal or oscillator.
Hardware reset ball (active Low). This reset input is required minimum of
10 ms low after stable supply voltage 3.3V.
J5
A7
I
Address 7
H5
A6
I
Address 6
K6
A5
I
Address 5
2020 Microchip Technology Inc.
DS00003459A-page 15
KSZ8842-16M/-32M
TABLE 2-2:
BALL DESCRIPTION FOR KSZ8842-16MBL (8-/16-BIT) (CONTINUED)
Ball
Number
Ball Name
Type
J6
A4
I
Address 4
H6
A3
I
Address 3
K7
A2
I
Address 2
J7
A1
I
Address 1
H7
BE1N
I
Byte Enable 1 Not, Active low for Data byte 1 enable (don’t care in 8-bit
bus mode).
K8
BE0N
I
Byte Enable 0 Not, Active low for Data byte 0 enable (there is an internal
inverter enabled and connected to the BE1N for 8-bit bus mode).
Function
K9
D15
I/O
Data 15
K10
D14
I/O
Data 14
J9
D13
I/O
Data 13
J10
D12
I/O
Data 12
J8
D11
I/O
Data 11
H9
D10
I/O
Data 10
H10
D9
I/O
Data 9
H8
D8
I/O
Data 8
G9
D7
I/O
Data 7
G10
D6
I/O
Data 6
G8
D5
I/O
Data 5
F9
D4
I/O
Data 4
F10
D3
I/O
Data 3
F8
D2
I/O
Data 2
E9
D1
I/O
Data 1
E10
D0
I/O
Data 0
C4
VDDCO
P
1.2V digital core voltage output (internal 1.2V LDO power supply output),
this 1.2V output ball provides power to all VDDC/VDDA balls.
Note: Internally generated power voltage. Do not connect an external
power supply to this ball. This ball is used for connecting external filter
(Ferrite bead and capacitors). It is recommended this ball should be connected to 3.3V power rail by a 100Ω resistor for the internal LDO application.
C5
VDDC
P
1.2V digital core VDD input power supply from VDDCO (ball C4) through
external Ferrite bead and capacitor.
D3, E3, F3
VDDA
P
1.2V analog VDD input power supply from VDDCO (ball C4) through
external Ferrite bead and capacitor.
E1
VDDATX
P
3.3V analog VDD input power supply with well decoupling capacitors.
E2
VDDARX
P
3.3V analog VDD input power supply with well decoupling capacitors.
D7, E7, F7,
G4, G5,
G6, G7
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
D4, D5, D6,
E4, E5, E6,
F4, F5, F6
GND
GND
D8, H1
NC
I
DS00003459A-page 16
All digital and analog grounds
No Connect
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
KSZ8842-32MQL 128-PIN PQFP
10 3
10 4
10 5
10 6
10 7
10 8
10 9
11 0
11 1
11 2
11 3
11 4
11 5
11 6
11 7
11 8
11 9
12 0
12 1
12 2
12 3
12 4
12 5
12 6
12 7
1 28
KSZ8842-32MQL
(Top View)
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
AG ND
VDDAP
AG ND
IS E T
NC
NC
AG ND
VDDA
TXP2
TXM 2
AG ND
RXP2
RXM 2
VDDARX
VDDATX
TXM 1
TXP1
AG ND
RXM 1
RXP1
NC
VDDA
AG ND
NC
NC
AG ND
TESTEN
SCANEN
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
DGND
VDDIO
RDYRTNN
BCLK
DATACSN
NC
SRDYN
INTRN
LDEVN
RDN
EECS
ARDY
CYCLEN
P2LED3
DGND
VDDCO
VLBUSN
EEEN
P1LED3
EEDO
EESK
EEDI
SWR
AEN
WRN
DGND
ADSN
PWRDN
AGND
VDDA
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
26
27
28
29
30
31
32
33
34
35
36
37
38
D 20
D 19
D 18
D 17
DG ND
V D D IO
D 16
D 15
D 14
D 13
D 12
D 11
D 10
D9
D8
D7
D6
D5
D4
D3
DGND
DGND
V D D IO
D2
D1
D0
102
101
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
75
74
73
72
71
70
69
68
67
66
65
D21
D22
D23
D24
D25
D26
D27
D28
D29
D30
VDDIO
VDDC
DGND
D31
BE0N
BE1N
BE2N
BE3N
A1
A2
A3
A4
A5
VDDIO
DGND
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
RSTN
X2
X1
FIGURE 2-4:
KSZ8842-32MVL 128-PIN LQFP
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
D27
D28
D29
D30
VDDIO
VDDC
DGND
D31
BE0N
BE1N
BE2N
BE3N
A1
A2
A3
A4
A5
VDDIO
DGND
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
RSTN
X2
X1
FIGURE 2-5:
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
KSZ8842-32MVL
(Top View)
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
AGN D
VDDAP
AGN D
ISET
NC
NC
AGN D
VDDA
TXP2
TXM 2
AGN D
RXP2
RXM 2
VDDARX
VDDATX
TXM 1
TXP1
AGN D
RXM 1
RXP1
NC
VDDA
AGN D
NC
NC
AGN D
VDDA
AGND
PW RDN
AD SN
DG ND
W RN
TESTEN
SCANEN
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
DGND
VDDIO
RDYRTNN
BCLK
DATACSN
NC
SRDYN
INTRN
LDEVN
RDN
EECS
ARDY
CYCLEN
P2LED3
DGND
VDDCO
VLBUSN
EEEN
P1LED3
EEDO
EESK
EEDI
SWR
AEN
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
26
27
28
29
30
31
32
D26
D25
D24
D23
D22
D21
D 20
D19
D18
D17
DGND
VDDIO
D16
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
DG ND
DG ND
VDDIO
D2
D1
D0
2020 Microchip Technology Inc.
DS00003459A-page 17
KSZ8842-16M/-32M
TABLE 2-3:
PIN DESCRIPTION FOR KSZ8842-32MQL/MVL (32-BIT)
Pin
Number
Pin Name
Type
1
TEST_EN
I
Test Enable
For normal operation, pull-down this pin to ground.
2
SCAN_EN
I
Scan Test Scan Mux Enable
For normal operation, pull-down this pin to ground.
Description
Port 1 and Port 2 LED Indicators, defined as follows
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0, 0] Default
[0, 1]
P1LED3/P2LED3
—
—
P1LED2/P2LED2
Link/Activity
100Link/Activity
P1LED1/P2LED1
Full-Duplex/Col
10Link/Activity
P1LED0/P2LED0
Speed
Full-Duplex
Reg. SGCR5 bit [15,9]
3
4
5
6
7
8
P1LED2
P1LED1
P1LED0
P2LED2
P2LED1
P2LED0
OPU
[1, 0]
[1, 1]
P1LED3/P2LED3
Activity
—
P1LED2/P2LED2
Link
—
P1LED1/P2LED1
Full-Duplex/Col
—
P1LED0/P2LED0
Speed
—
Note:
Link = On; Activity = Blink; Link/Act = On/Blink; Full-Duplex/
Col = On/Blink; Full-Duplex = On (Full-duplex); Off (Halfduplex); Speed = On (100BASE-T); Off (10BASE-T)
Note:
P1LED3 is pin 27. P2LED3 is pin 22.
Port 1 and Port 2 LED indicators for Repeater mode defined as follows:
Switch Global Control Register 5: SGCR5 bit
[15,9]
[0,0] Default
[0,1] [1,0] [1,1]
P1LED3/P2LED3
RPT_COL, RPT_ACT
—
P1LED2/P2LED2
RPT_Link3/RX,
RPT_ERR3
—
P1LED1/P2LED1
RPT_Link2/RX,
RPT_ERR2
—
P1LED0/P2LED0
RPT_Link1/RX,
RPT_ERR1
—
Note:
9
DGND
GND
10
VDDIO
P
11
RDYRTNN
DS00003459A-page 18
IPD
RPT_COL = Blink; RPT_Link3/RX (Host port) = On/Blink;
RPT_Link2/RX (Port 2) = On/Blink; RPT_Link1/RX (Port 1) =
On/Blink; RPT_ACT = on if any activity, RPT_ERR3/2/1 = RX
error on port 3, 2, or 1.
Digital ground.
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
Ready Return Not:
For VLBus-like mode: Asserted by the host to complete synchronous
read cycles. If the host doesn’t connect to this pin, assert this pin.
For burst mode (32-bit interface only): Host drives this pin low to signal
waiting states.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-3:
Pin
Number
12
PIN DESCRIPTION FOR KSZ8842-32MQL/MVL (32-BIT) (CONTINUED)
Pin Name
BCLK
Type
Description
IPD
Bus Interface Clock
Local bus clock for synchronous bus systems. Maximum frequency is
50 MHz.
This pin should be tied Low or unconnected if it is in asynchronous
mode.
13
DATACSN
IPU
DATA Chip Select Not (For KSZ8842-32 Mode only)
Chip select signal for QMU data register (QDRH, QDRL), active Low.
When DATACSN is Low, the data path can be accessed regardless of
the value of AEN, A15-A1, and the content of the BANK select register.
14
NC
OPU
No connect.
15
SRDYN
OPU
Synchronous Ready Not
Ready signal to interface with synchronous bus for both EISA-like and
VLBus-like extend accesses.
For VLBus-like mode, the falling edge of this signal indicates ready. This
signal is synchronous to the bus clock signal BCLK.
For burst mode (32-bit interface only), the KSZ8842M drives this pin low
to signal wait states.
16
INTRN
OPD
Interrupt
Active Low signal to host CPU to indicate an interrupt status bit is set,
this pin needs an external 4.7 kΩ pull-up resistor.
17
LDEVN
OPD
Local Device Not
Active Low output signal, asserted when AEN is Low and A15-A4
decode to the KSZ8842M address programmed into the high byte of the
base address register. LDEVN is a combinational decode of the Address
and AEN signal.
18
RDN
IPD
Read Strobe Not
Asynchronous read strobe, active-low.
19
EECS
OPU
EEPROM Chip Select
OPD
Asynchronous Ready
ARDY may be used when interfacing asynchronous buses to extend bus
access cycles. It is asynchronous to the host CPU or bus clock. This pin
needs an external 4.7 kΩ pull-up resistor.
20
ARDY
21
CYCLEN
IPD
Cycle Not
For VLBus-like mode cycle signal; this pin follows the addressing cycle
to signal the command cycle.
For burst mode (32-bit interface only), this pin stays High for read cycles
and Low for write cycles.
22
P2LED3
OPD
Port 2 LED indicator
See the description in pins 6, 7, and 8.
23
DGND
GND
Digital IO ground.
24
25
VDDCO
VLBUSN
2020 Microchip Technology Inc.
P
IPD
1.2V digital core voltage output (internal 1.2V LDO power supply output),
this 1.2V output pin provides power to VDDC, VDDA and VDDAP pins.
Note: Internally generated power voltage. Do not connect an external
power supply to this pin. This pin is used for connecting external filter
(Ferrite bead and capacitors). It is recommended this pin should be connected to 3.3V power rail by a 100Ω resistor for the internal LDO application.
VLBus-like Mode
Pull-down or float: Bus interface is configured for synchronous mode.
Pull-up: Bus interface is configured for 32-bit asynchronous mode or
EISA-like burst mode.
DS00003459A-page 19
KSZ8842-16M/-32M
TABLE 2-3:
PIN DESCRIPTION FOR KSZ8842-32MQL/MVL (32-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
26
EEEN
IPD
EEPROM Enable
EEPROM is enabled and connected when this pin is pulled up.
EEPROM is disabled when this pin is pulled down or no connect.
27
P1LED3
OPD
Port 1 LED indicator
See the description in pins 3, 4, and 5.
28
EEDO
OPD
EEPROM Data Out
This pin is connected to DI input of the serial EEPROM.
OPD
EEPROM Serial Clock
A 4 μs (OBCR[1:0] = 11 on-chip bus speed @ 25 MHz) or 800 ns
(OBCR[1:0] = 00 on-chip bus speed @ 125 MHz) serial output clock
cycle to load configuration data from the serial EEPROM.
29
EESK
Description
30
EEDI
IPD
EEPROM Data In
This pin is connected to DO output of the serial EEPROM when EEEN is
pull-up.
This pin can be pull-down for 8-bit bus mode, pull-up for 16-bit bus mode
or don’t care for 32-bit bus mode when EEEN is pull-down (without
EEPROM).
31
SWR
IPD
Synchronous Write/Read
Write/Read signal for synchronous bus accesses. Write cycles when
high and Read cycles when low.
32
AEN
IPU
Address Enable
Address qualifier for the address decoding, active-low.
33
WRN
IPD
Write Strobe Not
Asynchronous write strobe, active-low.
34
DGND
GND
Digital IO ground
35
ADSN
IPD
Address Strobe Not
For systems that require address latching, the rising edge of ADSN indicates the latching moment of A15-A1 and AEN.
36
PWRDN
IPU
Full-chip power-down.
(Low = Power down; High or floating = Normal operation).
37
AGND
GND
Analog ground
38
VDDA
P
39
AGND
GND
40
NC
—
No Connect
No Connect
1.2V analog VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
Analog ground
41
NC
—
42
AGND
GND
43
VDDA
P
1.2V analog VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
Analog ground
44
NC
—
No Connect
45
RXP1
I/O
Port 1 physical receive (MDI) or transmit signal (+ differential)
Port 1 physical receive (MDI) or transmit signal (– differential)
46
RXM1
I/O
47
AGND
GND
48
TXP1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (+ differential)
49
TXM1
I/O
Port 1 physical transmit (MDI) or receive (MDIX) signal (– differential)
50
VDDATX
P
3.3V analog VDD input power supply with well decoupling capacitors.
51
VDDARX
P
3.3V analog VDD
52
RXM2
I/O
DS00003459A-page 20
Analog ground
Port 2 physical receive (MDI) or transmit (MDIX) signal (– differential)
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 2-3:
PIN DESCRIPTION FOR KSZ8842-32MQL/MVL (32-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
53
RXP2
I/O
54
AGND
GND
55
TXM2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (– differential)
56
TXP2
I/O
Port 2 physical receive (MDI) or transmit (MDIX) signal (+ differential)
57
VDDA
P
58
AGND
GND
Analog ground
59
NC
IPU
No connect
60
NC
IPU
No connect
61
ISET
O
62
AGND
GND
63
VDDAP
P
64
AGND
GND
65
X1
I
66
X2
O
67
RSTN
IPU
68
A15
I
Address 15
69
A14
I
Address 14
70
A13
I
Address 13
71
A12
I
Address 12
72
A11
I
Address 11
73
A10
I
Address 10
74
A9
I
Address 9
75
A8
I
Address 8
76
A7
I
Address 7
Address 6
Description
Port 2 physical receive (MDI) or transmit (MDIX) signal (+ differential)
Analog ground
1.2 analog VDD input power supply from VDDCO (pin 24) through external Ferrite bead and capacitor.
Set physical transmits output current.
Pull down this pin with a 3.01 kΩ 1% resistor to ground.
Analog ground
1.2V analog VDD for PLL input power supply from VDDCO (pin 24)
through external Ferrite bead and capacitor.
Analog ground
25 MHz crystal or oscillator clock connection.
Pins (X1, X2) connect to a crystal. If an oscillator is used, X1 connects to
a 3.3V tolerant oscillator and X2 is a no connect.
Note: Clock requirement is ±50 ppm for either crystal or oscillator.
Hardware reset pin (active-low). This reset input is required minimum of
10 ms low after stable supply voltage 3.3V.
77
A6
I
78
DGND
GND
79
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
80
A5
I
Address 5
81
A4
I
Address 4
82
A3
I
Address 3
83
A2
I
Address 2
84
A1
I
Address 1
85
BE3N
I
Byte Enable 3 Not, Active low for Data byte 3 enable.
86
BE2N
I
Byte Enable 2 Not, Active low for Data byte 2 enable.
87
BE1N
I
Byte Enable 1 Not, Active-low for Data byte 1 enable.
88
BE0N
I
Byte Enable 0 Not, Active-low for Data byte 0 enable.
89
D31
I/O
90
DGND
GND
2020 Microchip Technology Inc.
Digital IO ground
Data 31
Digital core ground
DS00003459A-page 21
KSZ8842-16M/-32M
TABLE 2-3:
PIN DESCRIPTION FOR KSZ8842-32MQL/MVL (32-BIT) (CONTINUED)
Pin
Number
Pin Name
Type
Description
91
VDDC
P
1.2V digital core VDD input power supply from VDDCO (pin 24) through
external Ferrite bead and capacitor.
92
VDDIO
P
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
93
D30
I/O
Data 30
94
D29
I/O
Data 29
95
D28
I/O
Data 28
96
D27
I/O
Data 27
97
D26
I/O
Data 26
98
D25
I/O
Data 25
99
D24
I/O
Data 24
100
D23
I/O
Data 23
101
D22
I/O
Data 22
102
D21
I/O
Data 21
103
D20
I/O
Data 20
104
D19
I/O
Data 19
105
D18
I/O
Data 18
106
D17
I/O
Data 17
107
DGND
GND
108
VDDIO
P
109
D16
I/O
Data 16
110
D15
I/O
Data 15
111
D14
I/O
Data 14
112
D13
I/O
Data 13
113
D12
I/O
Data 12
114
D11
I/O
Data 11
115
D10
I/O
Data 10
116
D9
I/O
Data 9
117
D8
I/O
Data 8
118
D7
I/O
Data 7
119
D6
I/O
Data 6
120
D5
I/O
Data 5
121
D4
I/O
Data 4
Data 3
Digital IO ground
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
122
D3
I/O
123
DGND
GND
Digital IO ground
124
DGND
GND
Digital core ground
125
VDDIO
P
126
D2
I/O
Data 2
127
D1
I/O
Data 1
128
D0
I/O
Data 0
3.3V digital VDDIO input power supply for IO with well decoupling capacitors.
Legend: P = Power supply, GND = Ground, I/O = Bi-directional, I = Input, O = Output. IPD = Input with internal pulldown. IPU = Input with internal pull-up. OPD = Output with internal pull-down. OPU = Output with internal pull-up.
DS00003459A-page 22
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KSZ8842-16M/-32M
3.0
FUNCTIONAL DESCRIPTION
The KSZ8842M contains two 10/100 physical layer transceivers (PHYs), two MAC units, and a DMA channel integrated
with a Layer-2 switch.
The KSZ8842M contains a bus interface unit (BIU), which controls the KSZ8842M via an 8-, 16-, or 32-bit host interface.
Physical signal transmission and reception are enhanced through the use of analog circuits in the PHY that make the
design more efficient and allow for low power consumption.
3.1
3.1.1
Functional Overview: Physical Layer Transceiver
100BASE-TX TRANSMIT
The 100BASE-TX transmit function performs parallel-to-serial conversion, 4B/5B coding, scrambling, NRZ-to-NRZI conversion, and MLT3 encoding and transmission.
The circuitry starts with a parallel-to-serial conversion, which converts the MII data from the MAC into a 125 MHz serial
bit stream. The data and control stream is then converted into 4B/5B coding, followed by a scrambler. The serialized
data is further converted from NRZ-to-NRZI format, and then transmitted in MLT3 current output. The output current is
set by an external1% 3.01 kΩ resistor for the 1:1 transformer ratio.
The output signal has a typical rise/fall time of 4 ns and complies with the ANSI TP-PMD standard regarding amplitude
balance, overshoot, and timing jitter. The wave-shaped 10BASE-T output is also incorporated into the 100BASE-TX
transmitter.
3.1.2
100BASE-TX RECEIVE
The 100BASE-TX receiver function performs adaptive equalization, DC restoration, MLT3-to-NRZI conversion, data and
clock recovery, NRZI-to-NRZ conversion, de-scrambling, 4B/5B decoding, and serial-to-parallel conversion.
The receiving side starts with the equalization filter to compensate for inter-symbol interference (ISI) over the twisted
pair cable. Because the amplitude loss and phase distortion is a function of the cable length, the equalizer must adjust
its characteristics to optimize performance. In this design, the variable equalizer makes an initial estimation based on
comparisons of incoming signal strength against some known cable characteristics, and then tunes itself for optimization. This is an ongoing process and self-adjusts against environmental changes such as temperature variations.
Next, the equalized signal goes through a DC restoration and data conversion block. The DC restoration circuit is used
to compensate for the effect of baseline wander and to improve the dynamic range. The differential data conversion
circuit converts the MLT3 format back to NRZI. The slicing threshold is also adaptive.
The clock recovery circuit extracts the 125 MHz clock from the edges of the NRZI signal. This recovered clock is then
used to convert the NRZI signal into the NRZ format. This signal is sent through the de-scrambler followed by the 4B/
5B decoder. Finally, the NRZ serial data is converted to the MII format and provided as the input data to the MAC.
3.1.3
SCRAMBLER/DE-SCRAMBLER (100BASE-TX ONLY)
The purpose of the scrambler is to spread the power spectrum of the signal to reduce electromagnetic interference (EMI)
and baseline wander. Transmitted data is scrambled through the use of an 11-bit wide linear feedback shift register
(LFSR). The scrambler generates a 2047-bit non-repetitive sequence, and the receiver then de-scrambles the incoming
data stream using the same sequence as at the transmitter.
3.1.4
10BASE-T TRANSMIT
The 10BASE-T driver is incorporated with the 100BASE-TX driver to allow for transmission using the same magnetic.
They are internally wave-shaped and pre-emphasized into outputs with a typical 2.3V amplitude. The harmonic contents
are at least 27dB below the fundamental frequency when driven by an all-ones Manchester-encoded signal.
3.1.5
10BASE-T RECEIVE
On the receive side, input buffers and level detecting squelch circuits are employed. A differential input receiver circuit
and a phase-locked loop (PLL) perform the decoding function. The Manchester-encoded data stream is separated into
clock signal and NRZ data. A squelch circuit rejects signals with levels less than 400 mV or with short pulse widths to
prevent noise at the RXP-or-RXM input from falsely triggering the decoder. When the input exceeds the squelch limit,
the PLL locks onto the incoming signal and the KSZ8842M decodes a data frame. The receiver clock is maintained
active during idle periods in between data reception.
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DS00003459A-page 23
KSZ8842-16M/-32M
3.1.6
POWER MANAGEMENT
The KSZ8842M features per port power-down mode. To save power, the user can power-down the port that is not in
use by setting bit 11 in either P1CR4 or P1MBCR register for port 1 and setting bit 11 in either P2CR4 or P2MBCR register for port 2. To bring the port back up, reset bit 11 in these registers.
In addition, there is a full switch power-down mode. This mode shuts the entire switch down, when the PWRDN (pin 36)
is pulled down to low.
3.1.7
MDI/MDI-X AUTO CROSSOVER
To eliminate the need for crossover cables between similar devices, the KSZ8842M supports HP-Auto MDI/MDI-X and
IEEE 802.3u standard MDI/MDI-X auto crossover. HP-Auto MDI/MDI-X is the default.
The auto-sense function detects remote transmit and receive pairs and correctly assigns the transmit and receive pairs
for the KSZ8842M device. This feature is extremely useful when end users are unaware of cable types in addition to
saving on an additional uplink configuration connection. The auto-crossover feature can be disabled through the port
control registers.
The IEEE 802.3u standard MDI and MDI-X definitions are illustrated in Table 3-1.
TABLE 3-1:
MDI/MDI-X PIN DEFINITIONS
MDI
3.1.7.1
MDI-X
RJ-45 Pins
Signals
RJ-45 Pins
Signals
1
TD+
1
RD+
2
TD–
2
RD–
3
RD+
3
TD+
6
RD–
6
TD–
Straight Cable
A straight cable connects an MDI device to an MDI-X device, or an MDI-X device to an MDI device. Figure 3-1 depicts
a typical straight cable connection between a NIC card (MDI) and a switch or hub (MDI-X).
FIGURE 3-1:
TYPICAL STRAIGHT CABLE CONNECTION
10/100 Ethernet
Media Dependent Interface
10/100 Ethernet
Media Dependent Interface
1
1
2
2
Transmit Pair
Receive Pair
3
Straight
Cable
3
4
4
5
5
6
6
7
7
8
8
Receive Pair
Modular Connector
(RJ-45)
NIC
DS00003459A-page 24
Transmit Pair
Modular Connector
(RJ-45)
HUB
(Repeater or Switch)
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
3.1.7.2
Crossover Cable
A crossover cable connects an MDI device to another MDI device, or an MDI-X device to another MDI-X device.
Figure 3-2 shows a typical crossover cable connection between two switches or hubs (two MDI-X devices).
FIGURE 3-2:
TYPICAL CROSSOVER CABLE CONNECTION
10/100 Ethernet
Media Dependent Interface
1
Receive Pair
10/100 Ethernet
Media Dependent Interface
Crossover
Cable
1
Receive Pair
2
2
3
3
4
4
5
5
6
6
7
7
8
8
Transmit Pair
Transmit Pair
Modular Connector (RJ-45)
HUB
(Repeater or Switch)
3.1.8
Modular Connector (RJ-45)
HUB
(Repeater or Switch)
AUTO-NEGOTIATION
The KSZ8842M conforms to the auto negotiation protocol as described by the 802.3 committee to allow the channel to
operate at 10BASE-T or 100BASE-TX.
Auto negotiation allows unshielded twisted pair (UTP) link partners to select the best common mode of operation. In
auto negotiation, the link partners advertise capabilities across the link to each other. If auto negotiation is not supported
or the link partner to the KSZ8842M is forced to bypass auto negotiation, the mode is set by observing the signal at the
receiver. This is known as parallel mode because while the transmitter is sending auto negotiation advertisements, the
receiver is listening for advertisements or a fixed signal protocol.
The link up process is shown in Figure 3-3.
2020 Microchip Technology Inc.
DS00003459A-page 25
KSZ8842-16M/-32M
FIGURE 3-3:
AUTO-NEGOTIATION AND PARALLEL OPERATION
START AUTO-NEGOTIATION
FORCE LINK SETTING
NO
PARALLEL
OPERATION
YES
BYPASS AUTO-NEGOTIATION
AND SET LINK MODE
ATTEMPT AUTONEGOTIATION
LISTEN FOR 100BASE-TX
IDLES
LISTEN FOR 10BASE-T
LINK PULSES
NO
JOIN FLOW
LINK MODE SET?
YES
LINK MODE SET
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KSZ8842-16M/-32M
3.1.9
LINKMD® CABLE DIAGNOSTICS
The KSZ8842M LinkMD® uses time domain reflectometry (TDR) to analyze the cabling plant for common cabling problems such as open circuits, short circuits, and impedance mismatches.
LinkMD works by sending a pulse of known amplitude and duration down the MDI and MDI-X pairs and then analyzes
the shape of the reflected signal. Timing the pulse duration gives an indication of the distance to the cabling fault with a
maximum distance of 200m and an accuracy of ±2m. Internal circuitry displays the TDR information in a user-readable
digital format in registers P1VCT[8:0] or P2VCT[8:0].
Note that cable diagnostics are only valid for copper connections. Fiber-optic operation is not supported.
3.1.9.1
Access
LinkMD is initiated by accessing register P1VCT/P2VCT, the LinkMD Control/Status register, in conjunction with register
P1CR4/P2CR4, the 100BASE-TX PHY Controller register.
3.1.9.2
Usage
LinkMD can be run at any time by making sure Auto-MDIX has been disabled. To disable Auto-MDIX, write a ‘1’ to
P1CR4[10] for port 1 or P2CR4[10] for port 2 to enable manual control over the pair used to transmit the LinkMD pulse.
The self-clearing cable diagnostic test enable bit, P1VCT[15] for port 1 or P2VCT[15] for port 2, is set to ‘1’ to start the
test on this pair.
When bit P1VCT[15] or P2VCT[15] returns to ‘0’, the test is complete. The test result is returned in bits P1VCT[14:13]
or P2VCT[14:13] and the distance is returned in bits P1VCT[8:0] or P2VCT[8:0]. The cable diagnostic test results are
as follows:
00 = Valid test, normal condition
01 = Valid test, open circuit in cable
10 = Valid test, short circuit in cable
11 = Invalid test, LinkMD failed
If P1VCT[14:13] = 11 or P2VCT[14:13] = 11, this indicates an invalid test, and occurs when the KSZ8842M is unable to
shut down the link partner. In this instance, the test is not run, as it is not possible for the KSZ8842M to determine if the
detected signal is a reflection of the signal generated or a signal from another source.
Cable distance can be approximated by the following formula:
P1VCT[8:0] x 0.4m for port 1 cable distance
P2VCT[8:0] x 0.4m for port 2 cable distance
This constant may be calibrated for different cabling conditions, including cables with a velocity of propagation that varies significantly from the norm.
3.2
3.2.1
Functional Overview: MAC and Switch
ADDRESS LOOKUP
The internal lookup table stores MAC addresses and their associated information. It contains a 1K entry unicast address
learning table plus switching information.
The KSZ8842M is guaranteed to learn 1K addresses and distinguishes itself from hash-based lookup tables, which
depending on the operating environment and probabilities, may not guarantee the absolute number of addresses it can
learn.
3.2.2
LEARNING
The internal lookup engine updates its table with a new entry if the following conditions are met:
• The received packet's Source Address (SA) does not exist in the lookup table.
• The received packet is good without receiving errors; the packet size is legal length.
The lookup engine inserts the qualified SA into the table, along with the port number and time stamp. If the table is full,
then the last entry of the table is deleted to make room for the new entry.
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DS00003459A-page 27
KSZ8842-16M/-32M
3.2.3
MIGRATION
The internal look-up engine also monitors whether a station has moved. If a station has moved, it updates the table
accordingly. Migration happens when the following conditions are met:
• The received packet's SA is in the table but the associated source port information is different.
• The received packet is good without receiving errors; the packet size is legal length.
The lookup engine updates the existing record in the table with the new source port information.
3.2.4
AGING
The lookup engine updates the time stamp information of a record whenever the corresponding SA appears. The time
stamp is used in the aging process. If a record is not updated for a period of time, the lookup engine removes the record
from the table. The lookup engine constantly performs the aging process and continuously removes aging records. The
aging period is about 200 seconds. This feature can be enabled or disabled through Global Register SGCR1[10].
3.2.5
FORWARDING
The KSZ8842M forwards packets using the algorithm that is depicted in the following flowcharts. Figure 3-4 shows stage
one of the forwarding algorithm where the search engine looks up the VLAN ID, static table, and dynamic table for the
destination address, and comes up with “port to forward 1” (PTF1). PTF1 is then further modified by spanning tree,
IGMP snooping, port mirroring, and port VLAN processes to come up with “port to forward 2” (PTF2), as shown in
Figure 3-5. The packet is sent to PTF2.
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KSZ8842-16M/-32M
FIGURE 3-4:
DESTINATION ADDRESS LOOKUP FLOW CHART IN STAGE ONE
Start
PTF1 = NULL
NO
VLAN ID
valid?
- Search VLAN table
- Ingress VLAN filtering
- Discard NPVID check
YES
Search complete.
Get PTF1 from
Static MAC Table
FOUND
Search Static
Table
This search is based on
DA or DA+FID
NOT
FOUND
Search complete.
Get PTF1 from
Dynamic MAC Table
FOUND
Dynamic Table
Search
This search is based on
DA+FID
NOT
FOUND
Search complete.
Get PTF1 from
VLAN table
PTF1
2020 Microchip Technology Inc.
DS00003459A-page 29
KSZ8842-16M/-32M
FIGURE 3-5:
DESTINATION ADDRESS RESOLUTION FLOW CHART IN STAGE TWO
PTF1
Spanning Tree
Process
- Check receiving port's receive enable bit
- Check destination port's transmit enable bit
- Check whether packets are special (BPDU)
or specified
- Applied to MAC #1 and MAC #2
IGMP Process
- IGMP will be forwarded to the host port
Port Mirror
Process
- RX Mirror
- TX Mirror
- RX or TX Mirror
- RX and TX Mirror
Port VLAN
Membership
Check
PTF2
The KSZ8842M will not forward the following packets:
• Error packets.
These include framing errors, Frame Check Sequence (FCS) errors, alignment errors, and illegal size packet errors.
• 802.3x pause frames.
The KSZ8842M intercepts these packets and performs the flow control.
• Local packets.
Based on destination address (DA) look-up. If the destination port from the lookup table matches the port from which
the packet originated, the packet is defined as local.
3.2.6
SWITCHING ENGINE
The KSZ8842M features a high-performance switching engine to move data to and from the MAC’s packet buffers. It
operates in store and forward mode, while the efficient switching mechanism reduces overall latency.
The switching engine has a 32 KB internal frame buffer. This resource is shared between all the ports. There are a total
of 256 buffers available. Each buffer is sized at 128B.
3.2.7
MAC OPERATION
The KSZ8842M strictly abides by IEEE 802.3 standards to maximize compatibility. Additionally, there is an added MAC
filtering function to filter unicast packets. The MAC filtering function is useful in applications such as VoIP where restricting certain packets reduces congestion and thus improves performance.
DS00003459A-page 30
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KSZ8842-16M/-32M
3.2.8
INTER PACKET GAP (IPG)
If a frame is successfully transmitted, the minimum 96-bit time for IPG is measured between two consecutive packets.
If the current packet is experiencing collisions, the minimum 96-bit time for IPG is measured from carrier sense (CRS)
to the next transmit packet.
3.2.9
BACK-OFF ALGORITHM
The KSZ8842M implements the IEEE standard 802.3 binary exponential back-off algorithm in half-duplex mode, and
optional aggressive mode back-off. After 16 collisions, the packet is optionally dropped depending upon the switch configuration in SGCR1[8].
3.2.10
LATE COLLISION
If a transmit packet experiences collisions after 512 bit times of the transmission, then the packet is dropped.
3.2.11
LEGAL PACKET SIZE
The KSZ8842M discards packets less than 64 bytes and can be programmed to accept packet size up to 1536 bytes in
SGCR2[1]. The KSZ8842M can also be programmed for special applications to accept packet size up to 1916 bytes in
SGCR2[2].
3.2.12
FLOW CONTROL
The KSZ8842M supports standard 802.3x flow control frames on both transmit and receive sides.
On the receive side, if the KSZ8842M receives a pause control frame, the KSZ8842M will not transmit the next normal
frame until the timer, specified in the pause control frame, expires. If another pause frame is received before the current
timer expires, the timer will be updated with the new value in the second pause frame. During this period (while it is flow
controlled), only flow control packets from the KSZ8842M are transmitted.
On the transmit side, the KSZ8842M has intelligent and efficient ways to determine when to invoke flow control. The
flow control is based on availability of the system resources, including available buffers, available transmit queues, and
available receive queues.
The KSZ8842M will flow control a port that has just received a packet if the destination port resource is busy. The
KSZ8842M issues a flow control frame (Xoff), containing the maximum pause time defined in IEEE standard 802.3x.
Once the resource is freed up, the KSZ8842M sends out the other flow control frame (Xon) with zero pause time to turn
off the flow control (turn on transmission to the port). A hysteresis feature is provided to prevent the flow control mechanism from being constantly activated and deactivated.
The KSZ8842M flow controls all ports if the receive queue becomes full.
3.2.13
HALF-DUPLEX BACKPRESSURE
A half-duplex backpressure option (not in IEEE 802.3 standards) is also provided. The activation and deactivation conditions are the same in full-duplex mode. If backpressure is required, the KSZ8842M sends preambles to defer the other
stations' transmission (carrier sense deference).
To avoid jabber and excessive deference (as defined in the 802.3 standard), after a certain time, the KSZ8842M discontinues the carrier sense and then raises it again quickly. This short silent time (no carrier sense) prevents other stations
from sending out packets thus keeping other stations in a carrier sense deferred state. If the port has packets to send
during a backpressure situation, the carrier sense type backpressure is interrupted and those packets are transmitted
instead. If there are no additional packets to send, carrier sense type backpressure is reactivated again until switch
resources free up. If a collision occurs, the binary exponential back-off algorithm is skipped and carrier sense is generated immediately, thus reducing the chance of further collisions and carrier sense is maintained to prevent packet reception.
To ensure no packet loss in 10BASE-T or 100BASE-TX half-duplex modes, the user must enable the following:
• Aggressive back off (bit 8 in SGCR1)
• No excessive collision drop (bit 3 in SGCR2)
Note:
These bits are not set in default, because this is not the IEEE standard.
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3.2.14
BROADCAST STORM PROTECTION
The KSZ8842M has an intelligent option to protect the switch system from receiving too many broadcast packets. As
the broadcast packets are forwarded to all ports except the source port, an excessive number of switch resources (bandwidth and available space in transmit queues) may be utilized. The KSZ8842M has the option to include “multicast packets” for storm control. The broadcast storm rate parameters are programmed globally, and can be enabled or disabled
on a per port basis in P1CR1[7] and P2CR1[7]. The rate is based on a 67 ms interval for 100BT and a 670 ms interval
for 10BT. At the beginning of each interval, the counter is cleared to zero and the rate limit mechanism starts to count
the number of bytes during the interval. The rate definition is described in SGCR3[2:0][15:8]. The default setting is 0x63
(99 decimal). This is equal to a rate of 1%, calculated as follows:
148,800 frames/sec x 67 ms/interval x 1% = 99 frames/interval (approx.) = 0x63
Note:
3.2.15
148,800 frames/sec is based on 64-byte block of packets in 100BASE-T with 12 bytes of IPG and 8 bytes
of preamble between two packets.
REPEATER MODE
When the KSZ8842M is set to repeater mode (SGCR3[7] = 1), it only works on 100BT half-duplex mode. In repeater
enabled mode, all ingress packets will be broadcast to the other two ports without MAC address checking and learning.
Before setting to the repeater mode, the user has to set bit 13 (100 Mbps), bit 12 (auto-negotiation disabled) and bit 8
(half-duplex) in both P1MBCR and P2MBCR registers as well as set bit 6 (host half-duplex) in SGCR3 register for the
repeater mode.
The latency in repeater mode is defined from the 1st bit of DA into the ingress port 1 to the 1st bit of DA out of the egress
port 2. The minimum is 270 ns and the maximum is 310 ns (one clock skew of 25 MHz between TX and RX).
3.2.16
CLOCK GENERATOR
The X1 and X2 pins are connected to a 25 MHz crystal. X1 can also serve as the connector to a 3.3V, 25 MHz oscillator
(as described in the Pin Description and Configuration section).
The bus interface unit (BIU) uses BCLK (Bus Clock) for synchronous accesses. The maximum host port frequency is
50 MHz for VLBus-like and burst mode (32-bit interface only).
3.3
Bus Interface Unit (BIU)
The host interface of the BIU is designed to communicate with embedded processors. The host interface of the
KSZ8842M is a generic bus interface. Some glue logic may be required when the interface talks to various buses and
processors.
In terms of transfer type, the BIU can support two transfers: asynchronous transfer and synchronous transfer. To support
these transfers (asynchronous and synchronous), the BIU provides three groups of signals:
• Synchronous signals
• Asynchronous signals
• Common signals used for both synchronous and asynchronous transfers
Because both synchronous and asynchronous signals are independent of each other, synchronous burst transfer and
asynchronous transfer can be mixed or interleaved, but cannot be overlapped (due to the sharing of the common signals).
In terms of physical data bus size, the KSZ8842M supports 8-, 16-, and 32-bit host/industrial standard data bus sizes.
Given a physical data bus size, the KSZ8842M supports 8-, 16-, or 32-bit data transfers depending on the size of the
physical data bus. For example, for a 32-bit system/host data bus, it allows 8-, 16-, and 32-bit data transfers (KSZ884232MQL); for a 16-bit system/host data bus, it allows 8- and 16-bit data transfers (KSZ8842-16MQL); and for 8-bit system/host data bus, it only allows 8-bit data transfers (KSZ8842-16MQL).
Note that KSZ8842M does not support internal data byte-swap, but it does support internal data word-swap. This means
that the system/host data bus HD[7:0] has to connect to both D[7:0] and D[15:8] for 8-bit data bus interfaces. However,
the system/host data bus HD[15:8] and HD[7:0] just connects to D[15:8] and D[7:0], respectively, for 16-bit data bus
interface; there is no need to connect HD[31:24] and HD[23:16] to D[31:24] and D[23:16].
Table 3-2 describes the BIU signal grouping.
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TABLE 3-2:
Signal
BUS INTERFACE UNIT SIGNAL GROUPING
Type
Function
Common Signals
A[15:1]
I
Address
AEN
I
Address Enable
Address Enable asserted indicates memory address on the bus for DMA access and because
the device is an I/O device, address decoding is only enabled when AEN is Low.
Byte Enable
BE3N,
BE2N,
BE1N,
BE0N
I
BE0N
BE1N
BE2N
BE3N
0
0
0
0
32-bit access (32-bit bus only)
Description
0
0
1
1
Lower 16-bit (D[15:0]) access
1
1
0
0
Higher 16-bit (D[31:16]) access
0
1
1
1
Byte 0 (D[7:0]) access
1
0
1
1
Byte 1 (D[15:8]) access
1
1
0
1
Byte 2 (D[23:16]) access (32-bit bus only)
1
1
1
0
Byte 3 (D[31:24]) access (32-bit bus only)
Note 1: BE3N, BE2N, BE1N, and BE0N are ignored when DATACSN is low because 32-bit
transfers are assumed.
Note 2: BE2N and BE3N are valid only for the KSZ8842-32 mode, and are No Connect for the
KSZ8842-16 mode.
D[31:16]
I/O
Data
For KSZ8842M-32 mode only.
D[15:0]
I/O
Data
For both KSZ8842-32 and KSZ8842-16 modes
ADSN
I
Address Strobe
The rising edge of ADSN is used to latch A[15:1], AEN, BE3N, BE2N, BE1N, and BE0N.
LDEVN
O
Local Device
This signal is a combinatorial decode of AEN and A[15:4]. This A[15:4] is used to compare
against the Base Address Register.
DATACSN
I
Data Register Chip Select (For KSZ8842-32 Mode only)
This signal is used for central decoding architecture (mostly for embedded application). When
asserted, the device’s local decoding logic is ignored and the 32-bit access to QMU Data Register is assumed.
INTRN
O
Interrupt
Synchronous Transfer Signals
VLBUSN
I
VLBUS
VLBUSN = 0, VLBus-like cycle.
VLBUSN = 1, Burst cycle (both host/system and KSZ8842M can insert wait state)
CYCLEN
I
CYCLEN
For VLBus-like access: used to sample SWR when asserted.
For burst access: used to connect to IOWC# bus signal to indicate burst write.
SWR
I
Write/Read
For VLBus-like access: used to indicate write (High) or read (Low) transfer.
For burst access: used to connect to IORC# bus signal to indicate burst read.
O
Synchronous Ready
For VLBus-like access: exactly the same signal definition of nSRDY in VLBus.
For burst access: insert wait state by KSZ8842M whenever necessary during the Data Register access.
SRDYN
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TABLE 3-2:
Signal
BUS INTERFACE UNIT SIGNAL GROUPING (CONTINUED)
Type
Function
RDYRTNN
I
Ready Return
For VLBus-like access: exactly like RDYRTNN signal in VLBus to end the cycle.
For burst access: exactly like EXRDY signal in EISA to insert wait states. Note that the wait
states are inserted by system logic (memory) not by KSZ8842M.
BCLK
I
Bus Clock
Asynchronous Transfer Signals
RDN
I
Asynchronous Read
WRN
I
Asynchronous Write
ARDY
O
Asynchronous Ready
This signal is asserted (Low) to insert wait states.
Note 3-1
I = Input. O = Output. I/O = Bi-directional.
Regardless of whether the transfer is synchronous or asynchronous, if the address latch is required, use the rising edge
of ADSN to latch the incoming signals A[15:1], AEN, BE3N, BE2N, BE1N, and BE0N.
Note that if the local device decoder is used in either synchronous or asynchronous transfers, LDEVN will be asserted
to indicate that the KSZ8842M is successfully targeted. The signal LDEVN is a combinatorial decode of AEN and
A[15:4].
3.3.1
ASYNCHRONOUS INTERFACE
For asynchronous transfers, the asynchronous dedicated signals RDN (for read) or WRN (for write) toggle, but the synchronous dedicated signals BCLK, CYCLEN, SWR, and RDYRTNN are de-asserted and stay at the same logic level
throughout the entire asynchronous transfer.
There is no data burst support for asynchronous transfer. All asynchronous transfers are single-data transfers. The BIU,
however, provides flexible asynchronous interfacing to communicate with various applications and architectures. Three
major ways of interfacing with the system (host) are.
• Interfacing with the system/host relying on local device decoding and having stable address throughout the whole
transfer: The typical example for this application is ISA-like bus interface using latched address signals as shown
in Figure 17. No additional address latch is required, therefore ADSN should be connected Low. The BIU decodes
A[15:4] and qualifies with AEN (Address Enable) to determine if the KSZ8842M switch is the intended target. The
host utilizes the rising edge of RDN to latch read data and the BIU will use rising edge of WRN to latch write data.
• Interfacing with the system/host relying on local device decoding but not having stable address throughout the
entire transfer: the typical example for this application is EISA-like bus (non-burst) interface as shown in Figure 18.
This type of interface requires ADSN to latch the address on the rising edge. The BIU decodes latched A[15:4]
and qualifies with AEN to determine if the KSZ8842M switch is the intended target. The data transfer is the same
as the first case.
• Interfacing with the system/host relying on central decoding (KSZ8842-32 mode only): The typical example for this
application is for an embedded processor having a central decoder on the system board or within the processor.
Connecting the chip select (CS) from system/host to DATACSN bypasses the local device decoder. When the
DATACSN is asserted, it only allows access to the Data Register in 32 bits and BE3N, BE2N, BE1N, and BE0N
are ignored as shown in Figure 19. No other registers can be accessed by asserting DATACSN. The data transfer
is the same as in the first case. Independent of the type of asynchronous interface used. To insert a wait state, the
BIU will assert ARDY to prolong the cycle.
3.3.2
SYNCHRONOUS INTERFACE
For synchronous transfers, the synchronous dedicated signals CYCLEN, SWR, and RDYRTNN will toggle but the asynchronous dedicated signals RDN and WRN are de-asserted and stay at the same logic level throughout the entire synchronous transfer.
The synchronous interface mainly supports two applications, one for VLBus-like and the other for EISA-like (DMA type
C) burst transfers. The VLBus-like interface supports only single-data transfer. The pin option VLBUSN determines if it
is a VLBus-like or EISA-like burst transfer. If VLBUSN = 0, the interface is for VLBus-like transfer; if VLBUSN = 1, the
interface is for EISA-like burst transfer.
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For VLBus-like transfer interface (VLBUSN = 0):
This interface is used in an architecture in which the device’s local decoder is utilized; that is, the BIU decodes latched
A [15:4] and qualifies with AEN (Address Enable) to determine if the switch is the intended target. No burst is supported
in this application. The M/nIO signal connection in VLBus is routed to AEN. The CYCLEN in this application is used to
sample the SWR signal when it is asserted. Usually, CYCLEN is one clock delay of ADSN. There is a handshaking process to end the cycle of VLBus-like transfers. When the KSZ8842M is ready to finish the cycle, it asserts SRDYN. The
system/host acknowledges SRDYN by asserting RDYRTNN after the system/host has latched the read data. The
KSZ8842M holds the read data until RDYRTNN is asserted. The timing waveform is shown in Figures 23 and 24.
For EISA-like burst transfer interface (VLBUSN = 1):
The SWR is connected to IORC# in EISA to indicate the burst read and CYCLEN is connected to IOWC# in EISA to
indicate the burst write. Note that in this application, both the system/host/memory and KSZ8842M are capable of inserting wait states. For system/host/memory to insert a wait state, assert the RDYRTNN signal; for the KSZ8842M to insert
the wait state, assert the SRDYN signal. The timing waveform is shown in Figures 21 and 22.
3.3.2.1
BIU Summation
Figure 3-6 shows the mapping from ISA-like, EISA-like, and VLBus-like transactions to the chip’s BIU.
Figure 3-7 shows the connection for different data bus sizes.
For detail 8/16-bit bus signal connections and descriptions refers to Application Note 132.
For detail 32-bit bus signal connections and descriptions refers to Application Note 137.
Note: For the 8-bit data bus mode, the internal inverter is enabled and connected between BE0N and BE1N, so an even
address will enable the BE0N and an odd address will enable the BE1N.
FIGURE 3-6:
MAPPING FROM THE ISA, EISA, AND VLBUS TO THE KSZ8842M BUS
INTERFACE
KSZ8842M BIU
Glue Logic
ISA
Non-burst
Glue Logic
No Addr Latch
(ADSN = 0)
Local
decode
Address Latch
Asynchronous
Interface
Central decode
EISA
Burst
VLBus
Glue Logic
Glue Logic
Central decode
(VLBUSN = 1)
Address Latch
Local
decode
(VLBUSN = 0)
Synchronous
Interface
Note: To use DATACSN & 32-bit only for Central decode
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FIGURE 3-7:
KSZ8842M 8-BIT, 16-BIT, AND 32-BIT DATA BUS CONNECTIONS
KSZ8842-16
KSZ8842-16
HA[1]
A[1]
HA[1]
A[1]
KSZ8842-32
GND
A[1]
HA[15:2]
A[15:2]
HA[15:2]
A[15:2]
HA[15:2]
A[15:2]
HD[7:0]
D[7:0]
HD[7:0]
D[7:0]
HD[7:0]
D[7:0]
D[15:8]
HD[15:8]
D[15:8]
HD[15:8]
D[15:8]
HD[23:16]
D[23:16]
HD[31:24]
D[31:24]
HA[0]
BE0N
HA[0]
BE0N
nHBE[0]
BE0N
VDD
BE1N
nSBHE
BE1N
nHBE[1]
BE1N
nHBE[2]
BE2N
nHBE[3]
BE3N
8-bit Data Bus
3.3.3
16-bit Data Bus
(for example: ISA-like)
32-bit Data Bus
(for example: EISA-like)
BIU IMPLEMENTATION PRINCIPLES
Because the KSZ8842M is an I/O device with 16 addressable locations, address decoding is based on the values of
A15-A4 and AEN. Whenever DATACSN is asserted, the address decoder is disabled and a 32-bit transfer to Data Register is assumed (BE3N – BE0N are ignored).
If address latching is required, the address is latched on the rising edge of ADSN and is transparent when ADSN = 0.
• Byte, word, and double word data buses and accesses (transfers) are supported.
• Internal byte swapping is not implemented and word swapping is supported internally. Refer to Figure 3-7 for the
appropriate 8-bit, 16-bit, and 32-bit data bus connection.
• Because independent sets of synchronous and asynchronous signals are provided, synchronous and asynchronous cycles can be mixed or interleaved as long as they are not active simultaneously.
• The asynchronous interface uses RDN and WRN signal strobes for data latching. If necessary, ARDY is deasserted on the leading edge of the strobe.
• The VLBUS-like synchronous interface uses BCLK, ADSN, and SWR and CYCLEN to control read and write
operations and generate SRDYN to insert the wait state, if necessary, when VLBUSN = 0. For read, the data must
be held until RDYRTNN is asserted.
• The EISA-like burst transfer is supported using synchronous interface signals and DATACSN when I/O signal
VLBUSN = 1. Both the system/host/memory and KSZ8842M are capable of inserting wait states. To set the system/host/memory to insert a wait state, assert RDYRTNN signal. To set the KSZ8842M to insert a wait state,
assert SRDYN signal.
3.4
Queue Management Unit (QMU)
The Queue Management Unit (QMU) manages packet traffic between the MAC/PHY interface and the system host. It
has built-in packet memory for receive and transmit functions called TXQ (Transmit Queue) and RXQ (Receive Queue).
Each queue contains 4 KB of memory for back-to-back, non-blocking frame transfer performance. It provides a group
of control registers for system control, frame status registers for current packet transmit/receive status, and interrupts
to inform the host of the real time TX/RX status.
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3.4.1
TRANSMIT QUEUE (TXQ) FRAME FORMAT
The frame format for the transmit queue is shown in Table 3-3. The first word contains the control information for the
frame to transmit. The second word is used to specify the total number of bytes of the frame. The packet data follows.
The packet data area holds the frame itself. It may or may not include the CRC checksum depending upon whether
hardware CRC checksum generation is enabled.
Multiple frames can be pipelined in both the transmit queue and receive queue as long as there is enough queue memory, thus avoiding overrun. For each transmitted frame, the transmit status information for the frame is located in the
TXSR register.
TABLE 3-3:
FRAME FORMAT FOR TRANSMIT QUEUE
Packet Memory Address Offset
Bit 15
2nd Byte
Bit 0
1st Byte
0
Control Word
2
Byte Count
Transmit Packet Data
4 and up
(maximum size is 1916)
Because multiple packets can be pipelined into the TX packet memory for transmit, the transmit status reflects the status
of the packet that is currently being transferred on the MAC interface, which may or may not be the last queued packet
in the TX queue.
The transmit control word is the first 16-bit word in the TX packet memory, followed by a 16-bit byte count. It must be
word aligned. Each control word corresponds to one TX packet. Table 3-4 gives the transmit control word bit fields.
TABLE 3-4:
TRANSMIT CONTROL WORD BIT FIELDS
Bit
Description
15
TXIC Transmit Interrupt on Completion
When this bit is set, the KSZ8842M sets the transmit interrupt after the present frame has been
transmitted.
14 - 10
Reserved.
9-8
TXDPN Transmit Destination Port Number
When bit is set, this field indicates the destination port(s) where the packet is forwarded from host
system. Set bit 8 to indicate that port 1 is the destination port. Set bit 9 to indicate that port 2 is the
destination port.
Setting all ports to 1 causes the switch engine to broadcast the packet to both ports.
Setting all bits to 0 has no effect. The internal switch engine forwards the packets according to the
switching algorithm in its MAC lookup table.
7-6
Reserved.
5-0
TXFID Transmit Frame ID
This field specifies the frame ID that is used to identify the frame and its associated status information in the transmit status register TXSR[5:0].
The transmit Byte Count specifies the total number of bytes to be transmitted from the TXQ. Its format is given in
Table 3-5.
TABLE 3-5:
Bit
TRANSMIT BYTE COUNT FORMAT
Description
15 - 11
Reserved.
10 - 0
TXBC Transmit Byte Count
Transmit Byte Count. Hardware uses the byte count information to conserve the TX buffer memory for better utilization of the packet memory.
Note: The hardware behavior is unknown if an incorrect byte count information is written to this
field. Writing a 0 value to this field is not permitted.
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The data area contains six bytes of Destination Address (DA) followed by six bytes of Source Address (SA), followed
by a variable-length number of bytes. On transmit, all bytes are provided by the CPU, including the source address. The
KSZ8842M does not insert its own SA. The 802.3 Frame Length word (Frame Type in Ethernet) is not interpreted by
the KSZ8842M. It is treated transparently as data both for transmit operations.
3.4.2
RECEIVE QUEUE (RXQ) FRAME FORMAT
The frame format for the receive queue is shown in Table 3-6. The first word contains the status information for the frame
received. The second word is the total number of bytes of the RX frame. Following that is the packet data area. The
packet data area holds the frame itself. It may or may not include the CRC checksum depending on whether hardware
CRC stripping is enabled.
TABLE 3-6:
FRAME FORMAT FOR RECEIVE QUEUE
Packet Memory
Address Offset
Bit 15
2nd Byte
Bit 0
1st Byte
0
Status Word
2
Byte Count
Receive Packet Data
4 and up
(maximum size is 1916)
For receive, the packet receive status always reflects the receive status of the packet received in the current RX packet
memory (see Table 3-7). The RXSR register indicates the status of the current received frame.
TABLE 3-7:
FRXQ RECEIVE PACKET STATUS
Bit
Description
15
RXFV Receive Frame Valid
When set, this field indicates that the present frame in the receive packet memory is valid. The
status information currently in this location is also valid.
When bit is reset, indicates that there is either no pending receive frame or current frame is still in
the process of receiving and has not completed yet.
14 - 10
9-8
Reserved.
RXSPN Receive Source Port Number
When bit is set, this field indicates the source port where the packet was received. (Setting bit 9 =
0 and bit 8 = 1 indicates the packet was received from port 1. Setting bit 9 = 1 and bit 8 = 0 indicates that the packet was received from port 2. Valid port is either port 1 or port 2.
7
RXBF Receive Broadcast Frame
When set, it indicates that this frame has a broadcast address.
6
RXMF Receive Multicast Frame
When set, it indicates that this frame has a multicast address (including the broadcast address).
5
RXUF Receive Unicast Frame
When set, it indicates that this frame has a unicast address.
4
Reserved.
3
RXFT Receive Frame Type
When set, it indicates that the frame is an Ethernet-type frame (frame length is greater than 1500
bytes). When clear, it indicates that the frame is an IEEE 802.3 frame.
This bit is not valid for runt frames.
2
RXTL Receive Frame Too Long
When set, it indicates that the frame length exceeds the maximum size of 1518 bytes. Frames that
are too long are passed to the host only if the pass bad frame bit is set.
Note: Frame too long is only a frame length indication and does not cause any frame truncation.
1
RXRF Receive Runt Frame
When set, it indicates that a frame was damaged by a collision or had a premature termination
before the collision window passed.
Runt frames are passed to the host only if the pass bad frame bit is set.
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TABLE 3-7:
Bit
FRXQ RECEIVE PACKET STATUS (CONTINUED)
Description
RXCE Receive CRC Error
When set, it indicates that a CRC error has occurred on the current received frame.
CRC error frames are passed to the host only if the pass bad frame bit is set.
0
Table 3-8 gives the format of the RX byte count field.
TABLE 3-8:
FRXQ RX BYTE COUNT FIELD
Bit
3.5
3.5.1
Description
15 - 11
Reserved.
10 - 0
RXBC Receive Byte Count
Receive Byte Count.
Advanced Switch Functions
SPANNING TREE SUPPORT
To support spanning tree, the host port is the designated port for the processor.
The other ports can be configured in one of the five spanning tree states via “transmit enable”, “receive enable”, and
“learning disable” register settings in registers P1CR2 and P2CR2 for ports 1 and 2, respectively. Table 3-9 shows the
port setting and software actions taken for each of the five spanning tree states.
TABLE 3-9:
SPANNING TREE STATES
State
Disable State: The port should not
forward or receive any packets.
Learning is disabled.
Blocking State: Only packets to
the processor are forwarded.
Listening State:
Only packets to and from the processor are forwarded. Learning is
disabled.
Learning State: Only packets to
and from the processor are forwarded. Learning is enabled.
2020 Microchip Technology Inc.
Port Setting
Software Action
Transmit enable = “0”,
Receive enable = “0”,
Learning disable = “1”
The processor should not send any packets to the
port. The switch may still send specific packets to
the processor (packets that match some entries in
the Static MAC Address Table with “overriding bit”
set) and the processor should discard those packets. Address learning is disabled on the port in this
state.
Transmit enable = “0”,
Receive enable = “0”,
Learning disable = “1”
The processor should not send any packets to the
port(s) in this state. The processor should program
the Static MAC Address Table with the entries that
it needs to receive (for example, BPDU packets).
The “overriding” bit should also be set so that the
switch will forward those specific packets to the
processor. Address learning is disabled on the port
in this state.
Transmit enable = “0”,
Receive enable = “0”,
Learning disable = “1”
The processor should program the Static MAC
table with the entries that it needs to receive (for
example, BPDU packets). The “overriding” bit
should be set so that the switch will forward those
specific packets to the processor. The processor
may send packets to the port(s) in this state.
Address learning is disabled on the port in this
state.
Transmit enable = “0”,
Receive enable = “0”,
Learning disable = “0”
The processor should program the Static MAC
Address Table with the entries that it needs to
receive (for example, BPDU packets). The “overriding” bit should be set so that the switch will forward
those specific packets to the processor. The processor may send packets to the port(s) in this state.
Address learning is enabled on the port in this
state.
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TABLE 3-9:
SPANNING TREE STATES (CONTINUED)
State
Forwarding State
Packets are forwarded and
received normally. Learning is
enabled.
3.5.2
Port Setting
Software Action
Transmit enable = “1”,
Receive enable = “1”,
Learning disable = “0”
The processor programs the Static MAC Address
Table with the entries that it needs to receive (for
example, BPDU packets). The “overriding” bit is set
so that the switch forwards those specific packets
to the processor. The processor can send packets
to the port(s) in this state. Address learning is
enabled on the port in this state.
IGMP SUPPORT
For Internet Group Management Protocol (IGMP) support in Layer 2, the KSZ8842M provides two components:
3.5.2.1
“IGMP” Snooping
The KSZ8842M traps IGMP packets and forwards them only to the processor (host port). The IGMP packets are identified as IP packets (either Ethernet IP packets, or IEEE 802.3 SNAP IP packets) with IP version = 0x4 and protocol
version number = 0x2.
3.5.2.2
“Multicast Address Insertion” in the Static MAC Table
Once the multicast address is programmed in the Static MAC Table, the multicast session is trimmed to the subscribed
ports, instead of broadcasting to all ports.
3.5.3
IPV6 MLD SNOOPING
The KSZ8842M traps IPv6 Multicast Listener Discovery (MLD) packets and forwards them only to the processor (host
port). MLD snooping is controlled by SGCR2 [13] (MLD snooping enable) and SGCR2 [12] (MLD option).
Setting SGCR2 [13] causes the KSZ8842M to trap packets that meet all of the following conditions:
•
•
•
•
IPv6 multicast packets
Hop count limit = 1
IPv6 next header = 1 or 58 (or = 0 with hop-by-hop next header = 1 or 58)
If SGCR2[12] = 1, IPv6 next header = 43, 44, 50, 51, or 60 (or = 0 with hop-by-hop next header = 43, 44, 50, 51,
or 60)
3.5.4
PORT MIRRORING SUPPORT
KSZ8842M supports “Port Mirroring” comprehensively as:
3.5.4.1
“Receive Only” Mirror on a Port
All the packets received on the port are mirrored on the sniffer port. For example, port 1 is programmed to be “receive
sniff” and the host port is programmed to be the “sniffer port”. A packet received on port 1 is destined to port 2 after the
internal lookup. The KSZ8842M forwards the packet to both port 2 and the host port. The KSZ8842M can optionally
even forward “bad” received packets to the “sniffer port”.
3.5.4.2
“Transmit Only” Mirror on a Port
All the packets transmitted on the port are mirrored on the sniffer port. For example, port 1 is programmed to be “transmit
sniff” and the host port is programmed to be the “sniffer port”. A packet received on port 2 is destined to port 1 after the
internal lookup. The KSZ8842M forwards the packet to both port 1 and the host port.
3.5.4.3
“Receive and Transmit Only” Mirror on a Port
All the packets received on port A and transmitted on port B are mirrored on the sniffer port. To turn on the “AND” feature,
set register SGCR2, bit 8 to “1”. For example, port 1 is programmed to be “receive sniff”, port 2 is programmed to be
“transmit sniff”, and the host port is programmed to be the “sniffer port”. A packet received on port 1 is destined to port
2 after the internal lookup. The KSZ8842M forwards the packet to both port 2 and the host port.
Multiple ports can be selected as “receive sniff” or “transmit sniff”. In addition, any port can be selected as the “sniffer
port”. All these per port features can be selected through registers P1CR2, P2CR2, and P3CR2 for ports 1, 2, and the
host port, respectively.
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3.6
IEEE 802.1Q VLAN Support
The KSZ8842M supports 16 active VLANs out of the 4096 possible VLANs specified in the IEEE 802.1Q specification.
KSZ8842M provides a 16-entry VLAN table, which converts the 12-bits VLAN ID (VID) to the 4-bits Filter ID (FID) for
address lookup. If a non-tagged or null-VID-tagged packet is received, the ingress port default VID is used for lookup.
In VLAN mode, the lookup process starts with VLAN table lookup to determine whether the VID is valid. If the VID is not
valid, the packet is dropped and its address is not learned. If the VID is valid, the FID is retrieved for further lookup. The
FID + Destination Address (FID+DA) are used to determine the destination port. The FID + Source Address (FID+SA)
are used for address learning (see Table 3-10 and Table 3-11).
TABLE 3-10:
FID + DA LOOKUP IN VLAN MODE
DA Found in
Static MAC Table
Use FID Flag
FID Match
DA+FID Found in
Dynamic MAC Table
No
Don’t Care
Don’t Care
No
Broadcast to the membership
ports defined in the VLAN Table
bits [18:16]
No
Don’t Care
Don’t Care
Yes
Send to the destination port
defined in the Dynamic MAC
Address Table bits [53:52]
Yes
0
Don’t Care
Don’t Care
Send to the destination port(s)
defined in the Static MAC
Address Table bits [50:48]
Yes
1
No
No
Broadcast to the membership
ports defined in the VLAN Table
bits [18:16]
Yes
1
No
Yes
Send to the destination port
defined in the Dynamic MAC
Address Table bits [53:52]
Yes
1
Yes
Don’t Care
TABLE 3-11:
Send to the destination port(s)
defined in the Static MAC
Address Table bits [50:48]
FID + SA LOOKUP IN VLAN MODE
FID+SA Found in
Dynamic MAC Table
3.7
Action
Action
No
Learn and add FID+SA to the Dynamic MAC Address Table
Yes
Update time stamp
QoS Priority Support
The KSZ8842M provides Quality of Service (QoS) for applications such as VoIP and video conferencing. Offering four
priority queues per port, the per-port transmit queue can be split into four priority queues: Queue 3 is the highest priority
queue and Queue 0 is the lowest priority queue. Bit 0 of registers P1CR1, P2CR1, and P3CR1 is used to enable split
transmit queues for ports 1, 2, and the host port, respectively.
3.7.1
PORT-BASED PRIORITY
With port-based priority, each ingress port is individually classified as a specific priority level. All packets received at the
high-priority receiving port are marked as high priority and are sent to the high-priority transmit queue if the corresponding transmit queue is split. Bits[4:3] of registers P1CR1, P2CR1, and P3CR1 is used to enable port-based priority for
Ports 1, 2, and the host port, respectively.
3.7.2
802.1P-BASED PRIORITY
For 802.1p-based priority, the KSZ8842 examines the ingress (incoming) packets to determine whether they are tagged.
If tagged, the 3-bit priority field in the VLAN tag is retrieved and used to look up the “priority mapping” value, as specified
by the register SGCR6. The “priority mapping” value is programmable.
Figure 3-8 illustrates how the 802.1p priority field is embedded in the 802.1Q VLAN tag.
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FIGURE 3-8:
802.1P PRIORITY FIELD FORMAT
802.1p based priority is enabled by bit[5] of registers P1CR1, P2CR1, and P3CR1 for Ports 1, 2, and the host port,
respectively.
The KSZ8842M provides the option to insert or remove the priority tagged frame's header at each individual egress port.
This header, consisting of the 2 bytes VLAN protocol ID (VPID) and the 2 bytes tag control information field (TCI), is also
referred to as the 802.1Q VLAN tag.
Tag insertion is enabled by bit [2] of registers P1CR1, P2CR1, and P3CR1 for Ports 1, 2, and the host port, respectively.
At the egress port, untagged packets are tagged with the ingress port’s default tag. The default tags are programmed
in register sets P1VIDCR, P2VIDCR, and P3VIDCR for Ports 1, 2, and the host port, respectively. The KSZ8842 does
not add tags to already tagged packets.
Tag removal is enabled by bit [1] of registers P1CR1, P2CR1, and P3CR1 for Ports 1, 2, and the host port, respectively.
At the egress port, tagged packets will have their 802.1Q VLAN Tags removed. The KSZ8842 will not modify untagged
packets.
The CRC is recalculated for both tag insertion and tag removal.
3.7.3
PRIORITY FIELD RE-MAPPING
This is a QoS feature that allows the KSZ8842M to set the “user priority ceiling” at any ingress port. If the ingress
packet’s priority field has a higher priority value than the default tag’s priority field of the ingress port, the packet’s priority
field is replaced with the default tag’s priority field. The “user priority ceiling” is enabled by bit[3] of registers P1CR2,
P2CR2, and P3CR2 for Ports 1, 2, and the host port, respectively.
3.7.4
DIFFSERV-BASED PRIORITY
DiffServ-based priority uses the ToS registers shown in the Type-of-Service (ToS) Priority Control Registers section. The
ToS priority control registers implement a fully-decoded, 128-bit differentiated services code point (DSCP) register to
determine packet priority from the 6-bit ToS field in the IP header. When the most significant 6 bits of the ToS field are
fully decoded, the resultant of the 64 possibilities is compared with the corresponding bits in the DSCP register to determine priority.
3.8
Rate-Limiting Support
The KSZ8842M supports hardware rate limiting from 64 Kbps to 99 Mbps, independently on the “receive side” and on
the “transmit side” as per port basis. For 10BASE-T, a rate setting above 10 Mbps means the rate is not limited. On the
receive side, the data receive rate for each priority at each port can be limited by setting up ingress rate control registers.
On the transmit side, the data transmit rate for each priority queue at each port can be limited by setting up egress rate
control registers. The size of each frame has options to include minimum inter-frame gap (IFG) or preamble byte, in
addition to the data field (from packet DA to FCS).
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For ingress rate limiting, KSZ8842M provides options to selectively choose frames from all types, multicast, broadcast,
and flooded unicast frames. The KSZ8842M counts the data rate from those selected type of frames. Packets are
dropped at the ingress port when the data rate exceeds the specified rate limit.
For egress rate limiting, the “leaky bucket” algorithm is applied to each output priority queue for shaping output traffic.
Inter frame gap is stretched on a per frame base to generate smooth, non-burst egress traffic. The throughput of each
output priority queue is limited by the egress rate specified.
If any egress queue receives more traffic than the specified egress rate throughput, packets may be accumulated in the
output queue and packet memory. After the memory of the queue or the port is used up, packet dropping or flow control
will be triggered. As a result of congestion, the actual egress rate may be dominated by flow control/dropping at the
ingress end, and may be therefore slightly less than the specified egress rate.
To reduce congestion, it is a good practice to make sure the egress bandwidth exceeds the ingress bandwidth.
3.8.1
MAC FILTERING FUNCTION
Use the static table to assign a dedicated MAC address to a specific port. When a unicast MAC address is not recorded
in the static table, it is also not learned in the dynamic MAC table. The KSZ8842M includes an option that can filter or
forward unicast packets for an unknown MAC address. This option is enabled by SGCR7 [7].
The unicast MAC address filtering function is useful in preventing the broadcast of unicast packets that could degrade
the quality of this port in applications such as voice over Internet Protocol (VoIP).
3.8.2
CONFIGURATION INTERFACE
The KSZ8842M operates only as a managed switch.
3.8.3
EEPROM INTERFACE
It is optional in the KSZ8842M to use an external EEPROM. In the case that an EEPROM is not used, the EEEN pin
must be tied Low or floating.
The external serial EEPROM with a standard microwire bus interface is used for non-volatile storage of information such
as the host MAC address, base address, and default configuration settings. The KSZ8842M can detect if the EEPROM
is a 1KB (93C46) or 4KB (93C66) EEPROM device (the 93C46 and the 93C66 are typical EEPROM devices). The
EEPROM is organized as 16-bit mode.
If the EEEN pin is pulled high, the KSZ8842M performs an automatic read of the external EEPROM words 0H to 6H
after the de-assertion of Reset. The EEPROM values are placed in certain host-accessible registers. EEPROM read/
write functions can also be performed by software read/writes to the EEPCR registers.
The KSZ8842M EEPROM format is shown in Table 3-12.
TABLE 3-12:
EEPROM FORMAT
Word
0H
15:8
7:0
Base Address
1H
Host MAC Address Byte 2
Host MAC Address Byte 1
2H
Host MAC Address Byte 4
Host MAC Address Byte 3
3H
Host MAC Address Byte 6
4H
Host MAC Address Byte 5
Reserved
5H
Reserved
6H
ConfigParam (see Table 3-13)
7H-3FH
Not used for KSZ8842M (available for user to use)
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The format for ConfigParam is shown in Table 3-13.
TABLE 3-13:
CONFIGPARAM WORD IN EEPROM FORMAT
Bit
Bit Name
Description
15 - 2
Reserved
Reserved
1
0
3.9
Clock Rate
Internal clock rate selection
0: 125 MHz
1: 25 MHz
Note: At power up, this chip operates on 125 MHz clock. The internal frequency can be dropped to 25 MHz via the external EEPROM.
ASYN 8-bit
Async 8-bit or 16-bit bus select
1= bus is configured for 16-bit width
0= bus is configured for 8-bit width
(32-bit width, KSZ8842-32, don’t care this bit setting)
Loopback Support
The KSZ8842M provides loopback support for remote diagnostic of failure. In loopback mode, the speed at both PHY
ports will be set to 100BASE-TX full-duplex mode. Two types of loopback are supported: Far-end Loopback and Nearend (Remote) Loopback.
3.9.1
NEAR-END (REMOTE) LOOPBACK
Near-end (Remote) loopback is conducted at PHY port 1 of the KSZ8842M. The loopback path starts at the PHY port’s
receive inputs (RXPx/RXMx), wraps around at the same PHY port’s PMD/PMA, and ends at the PHY port’s transmit
outputs (TXPx/TXMx).
Bit [1] of registers P1PHYCTRL and P2PHYCTRL is used to enable near-end loopback for ports 1 and 2, respectively.
Alternatively, Bit [9] of registers P1SCSLMD and P2SCSLMD can also be used to enable near-end loopback. The both
ports 1 and 2 near-end loopback paths are illustrated Figure 3-9.
3.9.2
FAR-END LOOPBACK
Far-end loopback is conducted between the KSZ8842M’s two PHY ports. The loopback path starts at the “Originating.”
PHY port’s receive inputs (RXP/RXM), wraps around at the “loopback” PHY port’s PMD/PMA, and ends at the “Originating” PHY port’s transmit outputs (TXP/TXM).
Bit [8] of registers P1CR4 and P2CR4 is used to enable far-end loopback for ports 1 and 2, respectively. Alternatively,
Bit [14] of registers P1MBCR and P2MBCR can also be used to enable far-end loopback. The port 2 far-end loopback
path is illustrated in Figure 3-10.
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KSZ8842-16M/-32M
FIGURE 3-9:
PORT 1 AND PORT 2 NEAR-END (REMOTE) LOOPBACK PATH
R X P 1 /
R X M 1
P H Y P o rt 1
N e a r-e n d (re m o te )
L o o p b a c k
T X P 1 /
T X M 1
P M D 1 /P M A 1
P C S 1
M A C 1
S w itc h
M A C 2
P C S 2
P M D 2 /P M A 2
T X P 2 /
T X M 2
FIGURE 3-10:
P H Y P o rt 2
N e a r-e n d (re m o te )
L o o p b a c k
R X P 2 /
R X M 2
PORT 2 FAR-END LOOPBACK PATH
R X P 1 /
R X M 1
O r ig in a tin g
P H Y P o rt 1
T X P 1 /
T X M 1
P M D 1 /P M A 1
P C S 1
M A C 1
S w it c h
M A C 2
P C S 2
P M D 2 /P M A 2
P H Y P o r t 2
F a r-en d L o o p b a ck
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KSZ8842-16M/-32M
4.0
REGISTER DESCRIPTIONS
4.1
CPU Interface I/O Registers
The KSZ8842M provides an EISA-like, ISA-like, or VLBUS-like bus interface for the CPU to access its internal I/O registers. I/O registers serve as the address that the microprocessor uses when communicating with the device. This is
used for configuring operational settings, reading or writing control, status information, and transferring packets by reading and writing through the packet data registers.
4.1.1
I/O REGISTERS
Input/Output (I/O) registers are limited to 16 locations as required by most ISA bus-based systems; therefore, registers
are assigned to different banks. The last word of the I/O register locations (0xE - 0xF) is shared by all banks and can
be used to change the bank in use.
The following I/O Space Mapping Tables apply to 8-, 16-, or 32-bit bus products. Depending upon the bus interface used
and byte enable signals (BE[3:0]N control byte access), each I/O access can be performed as an 8-bit, 16-bit, or 32-bit
operation. The KSZ8842M is not limited to 8/16-bit performance and 32-bit read/write are also supported.
TABLE 4-1:
INTERNAL I/O SPACE MAPPING - BANK 0 TO BANK 7
I/O Register Location
32-Bit
16-Bit
8-Bit
Bank Location
Bank 0
0x0
Base
Address
[7:0]
0x1
Base
Address
[15:8]
0x0 to 0x1
0x0 to 0x3
Bank 1
Reserved
0x2
0x2 to 0x3
Reserved
Reserved
0x3
0x4
QMU RX
Flow Control Watermark
[7:0]
0x5
QMU RX
Flow Control Watermark
[15:8]
0x6
Bus Error
Status
[7:0]
0x7
Bus Error
Status
[15:8]
0x8
Bus Burst
Length
[7:0]
0x9
Bus Burst
Length
[15:8]
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
DS00003459A-page 46
0xA
0xB
0xC
0xD
Bank 2
Bank 3
Host MAC
Address
Low [7:0]
On-Chip
Bus Control
[7:0]
Host MAC
Address
Low [15:8]
On-Chip
Bus Control
[15:8]
Host MAC
Address
Mid [7:0]
EEPROM
Control
[7:0]
Host MAC
Address
Mid [15:8]
EEPROM
Control
[15:8]
Host MAC
Address
High [7:0]
Memory
BIST Info
[7:0]
Host MAC
Address
High [15:8]
Memory
BIST Info
[15:8]
Bank 4
Reserved
Reserved
Reserved
Bank 5
Bank 6
Bank 7
Reserved
Reserved
Reserved
Reserved
Reserved
Global
Reset
[7:0]
Reserved
Global
Reset
[15:8]
Bus Configuration
[7:0]
Bus Configuration
[15:8]
Reserved
Reserved
Reserved
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
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KSZ8842-16M/-32M
TABLE 4-2:
INTERNAL I/O SPACE MAPPING - BANK 8 TO BANK 15
I/O Register Location
32-Bit
16-Bit
0x0 to 0x1
0x0 to 0x3
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
TABLE 4-3:
8-Bit
Bank Location
Bank 8
Bank 9
Bank 10 Bank 11 Bank 12 Bank 13 Bank 14 Bank 15
0x0
Reserved
0x1
0x2
Reserved
0x3
0x4
Reserved
0x5
0x6
Reserved
0x7
0x8
Reserved
0x9
0xA
Reserved
0xB
0xC
Bank Select [7:0]
0xD
0xE
Bank Select [15:8]
0xF
INTERNAL I/O SPACE MAPPING - BANK 16 TO BANK 23
I/O Register Location
32-Bit
16-Bit
8-Bit
Bank Location
Bank 16 Bank 17 Bank 18 Bank 19 Bank 20 Bank 21 Bank 22 Bank 23
0x0
Transmit
Control
[7:0]
TXQ Command [7:0]
Interrupt
Enable
[7:0]
Multicast
Table 0
[7:0]
0x1
Transmit
Control
[15:8]
TXQ Command
[15:8]
Interrupt
Enable
[15:8]
Multicast
Table 0
[15:8]
0x2
Transmit
Status
[7:0]
RXQ Command [7:0]
Interrupt
Status
[7:0]
Multicast
Table 1
[7:0]
0x3
Transmit
Status
[15:8]
RXQ Command
[15:8]
Interrupt
Status
[15:8]
Multicast
Table 1
[15:8]
0x4
Receive
Control
[7:0]
TX Frame
Data
Pointer
[7:0]
Receive
Status
[7:0]
Multicast
Table 2
[7:0]
0x5
Receive
Control
[15:8]
TX Frame
Data
Pointer
[15:8]
Receive
Status
[15:8]
Multicast
Table 2
[15:8]
RX Frame
Data
Pointer
[7:0]
Receive
Byte
Counter
[7:0]
Multicast
Table 3
[7:0]
RX Frame
Data
Pointer
[15:8]
Receive
Byte
Counter
[15:8]
Multicast
Table 3
[15:8]
0x0 to 0x1
0x0 to 0x3
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6
0x6 to 0x7
Reserved
0x7
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Reserved
Reserved
Reserved
Reserved
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TABLE 4-3:
INTERNAL I/O SPACE MAPPING - BANK 16 TO BANK 23 (CONTINUED)
I/O Register Location
32-Bit
16-Bit
8-Bit
0x8
QMU Data
Low
[7:0]
0x9
TXQ Memory Information
[15:8]
QMU Data
Low
[15:8]
0xA
RXQ Mem- QMU Data
ory InforHigh
mation [7:0] [7:0]
0xB
RXQ Memory Information
[15:8]
0x8 to 0xB
0xA to 0xB
0xC to 0xF
0xE to 0xF
TABLE 4-4:
0xC
0xD
Reserved
Reserved
QMU Data
High
[15:8]
Reserved
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
INTERNAL I/O SPACE MAPPING - BANK 24 TO BANK 31
I/O Register Location
32-Bit
Bank 16 Bank 17 Bank 18 Bank 19 Bank 20 Bank 21 Bank 22 Bank 23
TXQ Memory Information
[7:0]
0x8 to 0x9
0xC to 0xD
Bank Location
16-Bit
0x0 to 0x1
0x0 to 0x3
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
DS00003459A-page 48
8-Bit
0x0
0x1
0x2
0x3
0x4
0x5
0x6
0x7
0x8
0x9
0xA
0xB
0xC
0xD
0xE
0xF
Bank Location
Bank 24 Bank 25 Bank 26 Bank 27 Bank 28 Bank 29 Bank 30 Bank 31
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Bank Select [7:0]
Bank Select [15:8]
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TABLE 4-5:
INTERNAL I/O SPACE MAPPING - BANK 32 TO BANK 39
I/O Register Location
32-Bit
16-Bit
8-Bit
Switch
Global
Control 6
[7:0]
Switch ID
and Enable
[15:8]
Switch
Global
Control 6
[15:8]
0x2
Switch
Global
Control 1
[7:0]
Switch
Global
Control 7
[7:0]
0x3
Switch
Global
Control 1
[15:8]
Switch
Global
Control 7
[15:8]
0x4
Switch
Global
Control 2
[7:0]
0x5
Switch
Global
Control 2
[15:8]
0x6
Switch
Global
Control 3
[7:0]
0x7
Switch
Global
Control 3
[15:8]
0x8
Switch
Global
Control 4
[7:0]
0x9
Switch
Global
Control 4
[15:8]
0xA
Switch
Global
Control 5
[7:0]
0xB
Switch
Global
Control 5
[15:8]
0x0 to 0x1
0x1
0x0 to 0x3
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xF
0xE to 0xF
Bank 32 Bank 33 Bank 34 Bank 35 Bank 36 Bank 37 Bank 38 Bank 39
Switch ID
and Enable
[7:0]
0x0
0xC to 0xD
Bank Location
0xC
0xD
MAC
Address 1
[7:0]
Reserved
MAC
Address 1
[15:8]
MAC
Address 2
[7:0]
Reserved
MAC
Address 2
[15:8]
MAC
Address 3
[7:0]
Reserved
MAC
Address 3
[15:8]
Reserved
Reserved
Reserved
Reserved
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
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KSZ8842-16M/-32M
TABLE 4-6:
INTERNAL I/O SPACE MAPPING - BANK 40 TO BANK 47
I/O Register Location
32-Bit
16-Bit
8-Bit
Bank Location
Bank 40 Bank 41 Bank 42 Bank 43 Bank 44 Bank 45 Bank 46 Bank 47
PHY1 MIIDigital Test Register
Status [7:0] Basic Control [7:0]
PHY2 MIIRegister
Basic Control [7:0]
PHY1
LinkMD®
Control/
Status
[7:0]
PHY1 MIIRegister
Basic Control [15:8]
PHY2 MIIRegister
Basic Control [15:8]
PHY1
LinkMD®
Control/
Status
[15:8]
PHY1 MIIRegister
Analog Test
Basic StaStatus [7:0]
tus
[7:0]
PHY2 MIIRegister
Basic Status
[7:0]
PHY1
Special
Control/
Status
[7:0]
Indirect
Access
Data 1
[15:8]
PHY1 MIIAnalog Test
Register
Status
Basic Sta[15:8]
tus [15:8]
PHY2 MIIRegister
Basic Status [15:8]
PHY1
Special
Control/
Status
[15:8]
Indirect
Access
Data 2 [7:0]
Digital Test
Control
[7:0]
PHY2
PHY1
PHY2
LinkMD®
PHYID Low PHYID Low Control/
Status
[7:0]
[7:0]
[7:0]
Indirect
Access
Data 2
[15:8]
Digital Test
Control
[15:8]
PHY2
PHY1
PHY2
LinkMD®
PHYID Low PHYID Low Control/
Status
[15:8]
[15:8]
[15:8]
Indirect
Access
Data 3 [7:0]
PHY1
Analog Test
PHYID
Control 0
High
[7:0]
[7:0]
PHY2
PHYID
High
[7:0]
PHY2 Control/Status
[7:0]
PHY1
Analog Test
PHYID
Control 0
High
[15:8]
[15:8]
PHY2PHYID
High
[15:8]
PHY2 Control/Status
[15:8]
PHY1 A.N.
Analog Test
AdvertiseControl 1
ment
[7:0]
[7:0]
PHY2 A.N.
Advertisement
[7:0]
PHY1 A.N.
Analog Test
AdvertiseControl 1
ment
[15:8]
[15:8]
PHY2 A.N.
Advertisement
[15:8]
PHY1 A.N.
Analog Test
Link PartControl 2
ner Ability
[7:0]
[7:0]
PHY2 A.N.
Link Partner Ability
[7:0]
PHY1 A.N.
Analog Test
Link PartControl 2
ner Ability
[15:8]
[15:8]
PHY2 A.N.
Link Partner Ability
[15:8]
0x0
TOS Priority Control
1 [7:0]
TOS Priority Control
7 [7:0]
Indirect
Access
Control.
[7:0]
0x1
TOS Priority Control
1 [15:8]
TOS Priority Control
7 [15:8]
Indirect
Access
Control.
[15:8]
Digital Test
Status
[15:8]
0x2
TOS Priority Control
2 [7:0]
TOS Priority Control
8 [7:0]
Indirect
Access
Data 1
[7:0]
0x3
TOS Priority Control
2 [15:8]
TOS Priority Control
8 [15:8]
0x4
TOS Priority Control
3 [7:0]
0x5
TOS Priority Control
3 [15:8]
0x6
TOS Priority Control
4 [7:0]
0x7
TOS Priority Control
4 [15:8]
Indirect
Access
Data 3
[15:8]
0x8
TOS Priority Control
5 [7:0]
Indirect
Access
Data 4 [7:0]
0x9
TOS Priority Control
5 [15:8]
Indirect
Access
Data 4
[15:8]
0xA
TOS Priority Control
6 [7:0]
Indirect
Access
Data 5 [7:0]
0xB
TOS Priority Control
6 [15:8]
0x0 to 0x1
Reserved
0x0 to 0x3
0x2 to 0x3
Reserved
0x4 to 0x5
Reserved
0x4 to 0x7
0x6 to 0x7
Reserved
0x8 to 0x9
Reserved
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
DS00003459A-page 50
Reserved
0xC
0xD
Reserved
Indirect
Access
Data 5
[15:8]
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 4-7:
INTERNAL I/O SPACE MAPPING - BANK 48 TO BANK 55
I/O Register Location
32-Bit
16-Bit
8-Bit
Port 1 PHY
Special
Control/
Status,
LinkMD
[7:0]
Port 2
Control 1
[7:0]
Port 2 PHY
Special
Control/
Status,
LinkMD
[7:0]
Host Port
Control 1
[7:0]
Port 1
Control 1
[15:8]
Port 1 PHY
Special
Control/
Status,
LinkMD
[15:8]
Port 2
Control 1
[15:8]
Port 2 PHY
Special
Control/
Status,
LinkMD
[15:8]
Host Port
Control 1
[15:8]
0x2
Port 1
Control 2
[7:0]
Port 1
Control 4
[7:0]
Port 2
Control 2
[7:0]
Port 2
Control 4
[7:0]
Host Port
Control 2
[7:0]
0x3
Port 1
Control 2
[15:8]
Port 1
Control 4
[15:8]
Port 2
Control 2
[15:8]
Port 2
Control 4
[15:8]
Host Port
Control 2
[15:8]
0x4
Port 1 VID
Control
[7:0]
Port 1
Status
[7:0]
Port 2 VID
Control
[7:0]
Port 2
Status
[7:0]
Host Port
VID Control
[7:0]
0x5
Port 1 VID
Control
[15:8]
Port 1
Status
[15:8]
Port 2 VID
Control
[15:8]
Port 2
Status
[15:8]
Host Port
VID Control
[15:8]
0x6
Port 1
Control 3
[7:0]
0x7
Port 1
Control 3
[15:8]
0x8
Port 1
Ingress
Rate Control
[7:0]
0x9
Port 1
Ingress
Rate Control
[15:8]
0xA
Port 1
Egress
Rate Control
[7:0]
0xB
Port 1
Egress
Rate Control
[15:8]
0x0 to 0x1
0x1
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
Bank 48 Bank 49 Bank 50 Bank 51 Bank 52 Bank 53 Bank 54 Bank 55
Port 1
Control 1
[7:0]
0x0
0x0 to 0x3
Bank Location
0xC
0xD
Reserved
Reserved
Reserved
Port 2
Control 3
[7:0]
Port 2
Control 3
[15:8]
Port 2
Ingress
Rate Control
[7:0]
Port 2
Ingress
Rate Control
[15:8]
Port 2
Egress
Rate Control
[7:0]
Port 2
Egress
Rate Control
[15:8]
Reserved
Reserved
Reserved
Host Port
Control 3
[7:0]
Host Port
Control 3
[15:8]
Host Port
Ingress
Rate Control
[7:0]
Host Port
Ingress
Rate Control
[15:8]
Host Port
Egress
Rate Control
[7:0]
Host Port
Egress
Rate Control
[15:8]
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
2020 Microchip Technology Inc.
Reserved
DS00003459A-page 51
KSZ8842-16M/-32M
TABLE 4-8:
INTERNAL I/O SPACE MAPPING - BANK 56 TO BANK 63
I/O Register Location
32-Bit
16-Bit
0x0 to 0x1
0x0 to 0x3
0x2 to 0x3
0x4 to 0x5
0x4 to 0x7
0x6 to 0x7
0x8 to 0x9
0x8 to 0xB
0xA to 0xB
0xC to 0xD
0xC to 0xF
0xE to 0xF
4.2
8-Bit
Bank Location
Bank 56 Bank 57 Bank 58 Bank 59 Bank 60 Bank 61 Bank 62 Bank 63
0x0
Reserved
0x1
0x2
Reserved
0x3
0x4
Reserved
0x5
0x6
Reserved
0x7
0x8
Reserved
0x9
0xA
Reserved
0xB
0xC
Reserved
0xD
0xE
Bank Select [7:0]
0xF
Bank Select [15:8]
Register Map: MAC and PHY
Do not write to bit values or to registers defined as Reserved. Manipulating reserved bits or registers causes unpredictable and often fatal results. If the user wants to write to these reserved bits, the user has to read back these reserved
bits (RO or RW) first, then “OR” with the read value of the reserved bits and write back to these reserved bits.
Bit Type Definitions
• RO = Read only.
• RW = Read/Write.
• W1C = Write 1 to Clear (writing a one to this bit clears it).
Bank 0-63 Bank Select Register (0x0E): BSR (Same Location in all Banks)
The bank select register is used to select or to switch between different sets of register banks for I/O access. There are
a total of 64 banks available to select, including the built-in switch engine registers.
TABLE 4-9:
BANK 0-63 BANK SELECT REGISTER (0X0E)
Bit
Default Value
R/W
15 - 6
0x000
RO
Reserved
R/W
BSA Bank Select Address Bits
BSA bits select the I/O register bank in use.
This register is always accessible regardless of the register bank
currently selected.
Notes:
The bank select register can be accessed as a doubleword (32-bit)
at offset 0xC, as a word (16-bit) at offset 0xE, or as a byte (8-bit) at
offset 0xE.
A doubleword write to offset 0xC writes to the BANK Select Register but does not write to registers 0xC and 0xD; it only writes to register 0xE.
5-0
DS00003459A-page 52
0x00
Description
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 0 Base Address Register (0x00): BAR
This register holds the base address for decoding a device access. Its value is loaded from the external EEPROM
(0x0H) upon a power-on reset if the EEPROM Enable (EEEN) pin is tied to High. Its value can also be modified after
reset. Writing to this register does not store the value into the EEPROM. When the EEEN pin is tied to Low, the default
base address is 0x300.
TABLE 4-10:
BANK 0 BASE ADDRESS REGISTER (0X00)
Bit
Default Value
R/W
Description
15 - 8
0x03 if EEEN is Low or
the value from EEPROM
if EEEN is High
R/W
BARH Base Address High
These bits are compared against the address on the bus
ADDR[15:8] to determine the BASE for the KSZ8842M registers.
7-5
0x0 if EEEN is Low or the
value from EEPROM if
EEEN is High
R/W
BARL Base Address Low
These bits are compared against the address on the bus
ADDR[7:5] to determine the BASE for the KSZ8842M registers.
4-0
0x00
RO
Reserved
Bank 0 QMU RX Flow Control High Watermark Configuration Register (0x04): QRFCR
This register contains the user defined QMU RX Queue high watermark configuration bit as below.
TABLE 4-11:
BANK 0 QMU RX FLOW CONTROL HIGH WATERMARK CONFIGURATION
REGISTER (0X04)
Bit
Default Value
R/W
15 - 13
0x0
RO
Reserved
0
R/W
QMU RX Flow Control High Watermark Configuration
0 = 3 KBytes
1 = 2 KBytes
0x000
RO
Reserved
12
11 - 0
Description
Bank 0 Bus Error Status Register (0x06): BESR
This register flags the different kinds of errors on the host bus.
TABLE 4-12:
Bit
15
14 - 11
BANK 0 BUS ERROR STATUS REGISTER (0X06)
Default Value
0
—
R/W
Description
RO
IBEC Illegal Byte Enable Combination
1 = Illegal byte enable combination occurs. The illegal combination
value can be found from bit 14 to bit 11.
0 = Legal byte enable combination.
Write 1 to clear.
RO
IBECV Illegal Byte Enable Combination Value
Bit 14 = Byte enable 3.
Bit 13 = Byte enable 2.
Bit 12 = Byte enable 1.
Bit 11 = Byte enable 0.
This value is valid only when bit 15 is set to 1.
10
0
RO
SSAXFER Simultaneous Synchronous and Asnychronous
Transfers
1 = Synchronous and Asnychronous Transfers occur simultaneously.
0 = Normal.
Write 1 to clear.
9-0
0x000
RO
Reserved
2020 Microchip Technology Inc.
DS00003459A-page 53
KSZ8842-16M/-32M
Bank 0 Bus Burst Length Register (0x08): BBLR
Before the burst can be sent, the burst length needs to be programmed.
TABLE 4-13:
BANK 0 BUS BURST LENGTH REGISTER (0X08)
Bit
Default Value
R/W
Description
15
0
RO
Reserved
14 - 12
0x0
R/W
BRL Burst Length (for burst read and write)
000 = Single.
011 = Fixed burst read length of 4.
101 = Fixed burst read length of 8.
111 = Fixed burst read length of 16.
11 - 0
0x000
RO
Reserved
Bank 1: Reserved
Except Bank Select Register (0xE).
Bank 2 Host MAC Address Register Low (0x00): MARL
This register along with the other two Host MAC address registers are loaded starting at word location 0x1 of the
EEPROM upon hardware reset. The software driver can modify the register, but it will not modify the original Host MAC
address value in the EEPROM. These six bytes of Host MAC address in external EEPROM are loaded to these three
registers as mapping below:
• MARL[15:0] = EEPROM 0x1(MAC Byte 2 and 1)
• MARM[15:0] = EEPROM 0x2(MAC Byte 4 and 3)
• MARH[15:0] = EEPROM 0x3(MAC Byte 6 and 5)
The Host MAC address is used to define the individual destination address that the KSZ8842M responds to when
receiving frames. Network addresses are generally expressed in the form of 01:23:45:67:89:AB, where the bytes are
received from left to right, and the bits within each byte are received from right to left (LSB to MSB). For example, the
actual transmitted and received bits are on the order of 10000000 11000100 10100010 11100110 10010001 11010101.
These three registers value for Host MAC address 01:23:45:67:89:AB will be held as below:
• MARL[15:0] = 0x89AB
• MARM[15:0] = 0x4567
• MARH[15:0] = 0x0123
The following table shows the register bit fields:
TABLE 4-14:
BANK 2 HOST MAC ADDRESS REGISTER LOW (0X00)
Bit
Default Value
R/W
15 - 0
—
R/W
Description
MARL MAC Address Low
The least significant word of the MAC address.
Bank 2 Host MAC Address Register Middle (0x02): MARM
The following table shows the register bit fields for middle word of Host MAC address.
TABLE 4-15:
BANK 2 HOST MAC ADDRESS REGISTER MIDDLE (0X02)
Bit
Default Value
R/W
15 - 0
—
R/W
DS00003459A-page 54
Description
MARM MAC Address Middle
The middle word of the MAC address.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 2 Host MAC Address Register High (0x04): MARH
The following table shows the register bit fields for high word of Host MAC address.
TABLE 4-16:
BANK 2 HOST MAC ADDRESS REGISTER HIGH (0X04)
Bit
Default Value
R/W
15 - 0
—
R/W
Description
MARH MAC Address High
The Most significant word of the MAC address.
Bank 3 On-Chip Bus Control Register (0x00): OBCR
This register controls the on-chip bus speed for the KSZ8842M. It is used for power management when the external
host CPU is running at a slow frequency. The default of the on-chip bus speed is 125 MHz without EEPROM. When the
external host CPU is running at a higher clock rate, the on-chip bus should be adjusted for the best performance.
TABLE 4-17:
BANK 3 ON-CHIP BUS CONTROL REGISTER (0X00)
Bit
Default Value
R/W
15 - 2
—
RO
Reserved
R/W
OBSC On-Chip Bus Speed Control
00 = 125 MHz.
01 = 62.5 MHz.
10 = 41.66 MHz.
11 = 25 MHz.
Note: When external EEPROM is enabled, the bit 1 in Configparm
word (0x6H) is used to control this speed as below:
Bit 1 = 0, this value will be 00 for 125 MHz.
Bit 1 = 1, this value will be 11 for 25 MHz.
(User still can write these two bits to change speed after EEPROM
data loaded)
1-0
0x0
Description
Bank 3 EEPROM Control Register (0x02): EEPCR
To support an external EEPROM, tie the EEPROM Enable (EEEN) pin to High; otherwise, tie it to Low. If an external
EEPROM is not used, the default chip Base Address (0x300), and the software programs the host MAC address. If an
EEPROM is used in the design (EEPROM Enable pin to High), the chip Base Address and host MAC address are
loaded from the EEPROM immediately after reset. The KSZ8842M allows the software to access (read and write) the
EEPROM directly; that is, the EEPROM access timing can be fully controlled by the software if the EEPROM Software
Access bit is set.
TABLE 4-18:
BANK 3 EEPROM CONTROL REGISTER (0X02)
Bit
Default Value
R/W
15 - 5
—
RO
Reserved
4
0
R/W
EESA EEPROM Software Access
1 = Enable software to access EEPROM through bit 3 to bit 0.
0 = Disable software to access EEPROM.
3
—
RO
EECB EEPROM Status Bit
Data Receive from EEPROM. This bit directly reads the EEDI pin.
R/W
EECB EEPROM Control Bits
Bit 2 = Data Transmit to EEPROM. This bit directly controls the
device’s EEDO pin.
Bit 1 = Serial Clock. This bit directly controls the device’s EESK pin.
Bit 0 = Chip Select for EEPROM. This bit directly controls the
device’s EECS pin.
2-0
0x0
2020 Microchip Technology Inc.
Description
DS00003459A-page 55
KSZ8842-16M/-32M
Bank 3 Memory BIST Info Register (0x04): MBIR
TABLE 4-19:
BANK 3 MEMORY BIST INFO REGISTER (0X04)
Bit
Default Value
R/W
Description
15 - 13
0x0
RO
Reserved
12
—
RO
TXMBF TX Memory BIST Finish
When set, it indicates the Memory Built In Self Test completion for
the TX Memory.
11
—
RO
TXMBFA TX Memory BIST Fail
When set, it indicates the Memory Built In Self Test has failed.
10 - 5
—
RO
Reserved
4
—
RO
RXMBF RX Memory BIST Finish
When set, it indicates the Memory Built In Self Test completion for
the RX Memory.
3
—
RO
RXMBFA RX Memory BIST Fail
When set, it indicates the Memory Built In Self Test has failed.
2-0
—
RO
Reserved
Bank 3 Global Reset Register (0x06): GRR
This register controls the global reset function with information programmed by the CPU.
TABLE 4-20:
Bit
15 - 1
0
BANK 3 GLOBAL RESET REGISTER (0X06)
Default Value
0x0000
0
R/W
Description
RO
Reserved
R/W
Global Soft Reset
1 = Software reset is active.
0 = Software reset is inactive.
Software reset will affect PHY, MAC, QMU, DMA, and the switch
core, only the BIU (base address registers) remains unaffected by a
software reset.
Bank 3 Bus Configuration Register (0x08): BCFG
This register is a read-only register. The bit 0 is automatically downloaded from bit 0 Configparm word of EEPROM, if
pin EEEN is high (enabled EEPROM).
TABLE 4-21:
BUS CONFIGURATION REGISTER (0X08)
Bit
Default Value
R/W
15 - 1
0x0000
RO
Reserved
RO
Bus Configuration (only for KSZ8842-16 device)
1 = Bus width is 16 bits.
0 = Bus width is 8 bits.
(this bit is only available when EEPROM is enabled)
0
—
Description
Banks 4 - 15: Reserved
Except Bank Select Register (0xE).
DS00003459A-page 56
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 16 Transmit Control Register (0x00): TXCR
This register holds control information programmed by the CPU to control the QMU transmit module function.
TABLE 4-22:
Bit
BANK 16 TRANSMIT CONTROL REGISTER (0X00)
Default Value
R/W
15
—
RO
Reserved
14
0x0
RO
Reserved
13
0x0
RO
Reserved
12 - 4
—
RO
Reserved
R/W
TXFCE Transmit Flow Control Enable
When this bit is set, the QMU sends flow control pause frames from
the host port if the RX FIFO has reached its threshold.
Note: the SGCR3[5] in Bank 32 also needs to be enabled.
3
0x0
Description
2
0x0
R/W
TXPE Transmit Padding Enable
When this bit is set, the KSZ8842M automatically adds a padding
field to a packet shorter than 64 bytes.
Note: Setting this bit requires enabling the add CRC feature to
avoid CRC errors for the transmit packet.
1
0x0
R/W
TXCE Transmit CRC Enable
When this bit is set, the KSZ8842M automatically adds a CRC
checksum field to the end of a transmit frame.
R/W
TXE Transmit Enable
When this bit is set, the transmit module is enabled and placed in a
running state. When reset, the transmit process is placed in the
stopped state after the transmission of the current frame is completed.
0
0x0
Bank 16 Transmit Status Register (0x02): TXSR
This register keeps the status of the last transmitted frame.
TABLE 4-23:
BANK 16 TRANSMIT STATUS REGISTER (0X02)
Bit
Default Value
R/W
Description
15 - 6
0x000
RO
Reserved
5-0
—
RO
TXFID Transmit Frame ID
This field identifies the transmitted frame. All of the transmit status
information in this register belongs to the frame with this ID.
Bank 16 Receive Control Register (0x04): RXCR
This register holds control information programmed by the CPU to control the receive function.
TABLE 4-24:
BANK 16 RECEIVE CONTROL REGISTER (0X04)
Bit
Default Value
R/W
15 - 11
—
RO
Reserved
R/W
RXFCE Receive Flow Control Enable
When this bit is set, the KSZ8842M will acknowledge a PAUSE
frame from the receive interface; i.e., the outgoing packets are
pending in the transmit buffer until the PAUSE frame control timer
expires. When this bit is cleared, flow control is not enabled.
R/W
RXEFE Receive Error Frame Enable
When this bit is set, CRC error frames are allowed to be received
into the RX queue.
When this bit is cleared, all CRC error frames are discarded.
10
9
0x0
0x0
2020 Microchip Technology Inc.
Description
DS00003459A-page 57
KSZ8842-16M/-32M
TABLE 4-24:
BANK 16 RECEIVE CONTROL REGISTER (0X04) (CONTINUED)
Bit
Default Value
R/W
Description
8
—
RO
Reserved
7
0x0
R/W
RXBE Receive Broadcast Enable
When this bit is set, the RX module receives all the broadcast
frames.
6
0x0
R/W
RXME Receive Multicast Enable
When this bit is set, the RX module receives all the multicast
frames (including broadcast frames).
5
0x0
R/W
RXUE Receive Unicast
When this bit is set, the RX module receives unicast frames that
match the 48-bit Station MAC address of the module.
4
0x0
R/W
RXRA Receive All
When this bit is set, the KSZ8842M receives all incoming frames,
regardless of the frame’s destination address.
3
0x0
R/W
RXSCE Receive Strip CRC
When this bit is set, the KSZ8842M strips the CRC on the received
frames. Once cleared, the CRC is stored in memory following the
packet.
2
0x0
R/W
QMU Receive Multicast Hash-Table Enable
When this bit is set, this bit enables the RX function to receive multicast frames that pass the CRC Hash filtering mechanism.
1
—
RO
Reserved
R/W
RXE Receive Enable
When this bit is set, the RX block is enabled and placed in a running state.
When reset, the receive process is placed in the stopped state
upon completing reception of the current frame.
0
0x0
Bank 16 TXQ Memory Information Register (0x08): TXMIR
This register indicates the amount of free memory available in the TXQ of the QMU module.
TABLE 4-25:
BANK 16 TXQ MEMORY INFORMATION REGISTER (0X08)
Bit
Default Value
R/W
15 - 13
—
RO
Reserved
RO
TXMA Transmit Memory Available
The amount of memory available is represented in units of byte.
The TXQ memory is used for both frame payload, control word.
There is total 4096 bytes in TXQ.
Note: Software must be written to ensure that there is enough
memory for the next transmit frame including control information
before transmit data is written to the TXQ.
12 - 0
—
Description
Bank 16 RXQ Memory Information Register (0x0A): RXMIR
This register indicates the amount of receive data available in the RXQ of the QMU module.
TABLE 4-26:
Bit
15 - 13
BANK 16 RXQ MEMORY INFORMATION REGISTER (0X0A)
Default Value
—
DS00003459A-page 58
R/W
RO
Description
Reserved
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 4-26:
Bit
12 - 0
BANK 16 RXQ MEMORY INFORMATION REGISTER (0X0A) (CONTINUED)
Default Value
—
R/W
Description
RO
RXMA Receive Packet Data Available
The amount of Receive packet data available is represented in
units of byte. The RXQ memory is used for both frame payload, status word. There is total 4096 bytes in RXQ. This counter will update
after a complete packet is received and also issues an interrupt
when receive interrupt enable IER[13] in Bank 18 is set.
Note: Software must be written to empty the RXQ memory to allow
for the new RX frame. If this is not done, the frame may be discarded as a result of insufficient RXQ memory.
Bank 17 TXQ Command Register (0x00): TXQCR
This register is programmed by the Host CPU to issue a transmit command to the TXQ. The present transmit frame in
the TXQ memory is queued for transmit.
TABLE 4-27:
BANK 17 TXQ COMMAND REGISTER (0X00)
Bit
Default Value
R/W
15 - 1
—
RO
Reserved
R/W
TXETF Enqueue TX Frame
When this bit is written as 1, the current TX frame prepared in the
TX buffer is queued for transmit.
Note: This bit is self-clearing after the frame is finished transmitting.
The software should wait for the bit to be cleared before setting up
another new TX frame.
0
0x0
Description
Bank 17 RXQ Command Register (0x02): RXQCR
This register is programmed by the Host CPU to issue release command to the RXQ. The current frame in the RXQ
frame buffer is read only by the host and the memory space is released.
TABLE 4-28:
BANK 17 RXQ COMMAND REGISTER (0X02)
Bit
Default Value
R/W
15 - 1
—
RO
Reserved
R/W
RXRRF Release RX Frame
When this bit is written as 1, the current RX frame buffer is
released.
Note: This bit is self-clearing after the frame memory is released.
The software should wait for the bit to be cleared before processing
new RX frame.
0
0x0
Description
Bank 17 TX Frame Data Pointer Register (0x04): TXFDPR
The value of this register determines the address to be accessed within the TXQ frame buffer. When the AUTO increment is set, It will automatically increment the pointer value on Write accesses to the data register.
The counter is incremented by one for every byte access, by two for every word access, and by four for every double
word access.
TABLE 4-29:
BANK 17 TX FRAME DATA POINTER REGISTER (0X04)
Bit
Default Value
R/W
15
—
RO
2020 Microchip Technology Inc.
Description
Reserved
DS00003459A-page 59
KSZ8842-16M/-32M
TABLE 4-29:
Bit
BANK 17 TX FRAME DATA POINTER REGISTER (0X04) (CONTINUED)
Default Value
R/W
Description
14
0x0
R/W
TXFPAI TX Frame Data Pointer Auto Increment
When this bit is set, the TX Frame data pointer register increments
automatically on accesses to the data register. The increment is by
one for every byte access, by two for every word access, and by
four for every doubleword access.
When this bit is reset, the TX frame data pointer is manually controlled by user to access the TX frame location.
13 - 11
—
RO
Reserved
R/W
TXFP TX Frame Pointer
TX Frame Pointer index to the Frame Data register for access.
This field reset to next available TX frame location when the TX
Frame Data has been enqueued through the TXQ command register.
10 - 0
0x0
Bank 17 RX Frame Data Pointer Register (0x06): RXFDPR
The value of this register determines the address to be accessed within the RXQ frame buffer. When the Auto Increment
is set, it will automatically increment the RXQ Pointer on read accesses to the data register.
The counter is incremented is by one for every byte access, by two for every word access, and by four for every double
word access.
TABLE 4-30:
BANK 17 RX FRAME DATA POINTER REGISTER (0X06)
Bit
Default Value
R/W
Description
15
—
RO
Reserved
14
0x0
R/W
RXFPAI RX Frame Pointer Auto Increment
When this bit is set, the RXQ Address register increments automatically on accesses to the data register. The increment is by one for
every byte access, by two for every word access, and by four for
every double word access.
When this bit is reset, the RX frame data pointer is manually controlled by user to access the RX frame location.
13 - 11
—
RO
Reserved
R/W
RXFP RX Frame Pointer
RX Frame data pointer index to the Data register for access.
This field reset to next available RX frame location when RX Frame
release command is issued (through the RXQ command register).
10 - 0
0x000
Bank 17 QMU Data Register Low (0x08): QDRL
This register QDRL(0x08-0x09) contains the Low data word presently addressed by the pointer register. Reading maps
from the RXQ, and writing maps to the TXQ.
TABLE 4-31:
Bit
BANK 17 QMU DATA REGISTER LOW (0X08)
Default Value
15 - 0
DS00003459A-page 60
—
R/W
Description
R/W
QDRL Queue Data Register Low
This register is mapped into two uni-directional buffers for 16-bit
buses, and one uni-directional buffer for 32-bit buses, (TXQ when
Write, RXQ when Read) that allow moving words to and from the
KSZ8842M regardless of whether the pointer is even, odd, or
Dword aligned. Byte, word, and Dword access can be mixed on the
fly in any order. This register along with DQRH is mapped into two
consecutive word locations for 16-bit buses, or one word location
for 32-bit buses, to facilitate Dword move operations.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 17 QMU Data Register High (0x0A): QDRH
This register QDRH(0x0A-0x0B) contains the High data word presently addressed by the pointer register. Reading maps
from the RXQ, and writing maps to the TXQ.
TABLE 4-32:
Bit
15 - 0
BANK 17 QMU DATA REGISTER HIGH (0X0A)
Default Value
—
R/W
Description
R/W
QDRL Queue Data Register High
This register is mapped into two uni-directional buffers for 16-bit
buses, and one uni-directional buffer for 32-bit buses, (TXQ when
Write, RXQ when Read) that allow moving words to and from the
KSZ8842M regardless of whether the pointer is even, odd, or
Dword aligned. Byte, word, and Dword access can be mixed on the
fly in any order. This register along with DQRL is mapped into two
consecutive word locations for 16-bit buses, or one word location
for 32-bit buses, to facilitate Dword move operations.
Bank 18 Interrupt Enable Register (0x00): IER
This register enables the interrupts from the QMU and other sources.
TABLE 4-33:
BANK 18 INTERRUPT ENABLE REGISTER (0X00)
Bit
Default Value
R/W
15
0x0
R/W
LCIE Link Change Interrupt Enable
When this bit is set, the link change interrupt is enabled.
When this bit is reset, the link change interrupt is disabled.
14
0x0
R/W
TXIE Transmit Interrupt Enable
When this bit is set, the transmit interrupt is enabled.
When this bit is reset, the transmit interrupt is disabled.
13
0x0
R/W
RXIE Receive Interrupt Enable
When this bit is set, the receive interrupt is enabled.
When this bit is reset, the receive interrupt is disabled.
12
0x0
R/W
Reserved
11
0x0
R/W
RXOIE Receive Overrun Interrupt Enable
When this bit is set, the Receive Overrun interrupt is enabled.
When this bit is reset, the Receive Overrun interrupt is disabled.
10
0x0
R/W
Reserved
R/W
TXPSIE Transmit Process Stopped Interrupt Enable
When this bit is set, the Transmit Process Stopped interrupt is
enabled.
When this bit is reset, the Transmit Process Stopped interrupt is
disabled.
9
0x0
Description
8
0x0
R/W
RXPSIE Receive Process Stopped Interrupt Enable
When this bit is set, the Receive Process Stopped interrupt is
enabled.
When this bit is reset, the Receive Process Stopped interrupt is disabled.
7
0x0
R/W
RXEFIE Receive Error Frame Interrupt Enable
When this bit is set, the Receive error frame interrupt is enabled.
When this bit is reset, the Receive error frame interrupt is disabled.
6-0
—
RO
Reserved
2020 Microchip Technology Inc.
DS00003459A-page 61
KSZ8842-16M/-32M
Bank 18 Interrupt Status Register (0x02): ISR
This register contains the status bits for all QMU and other interrupt sources.
When the corresponding enable bit is set, it causes the interrupt pin to be asserted.
This register is usually read by the host CPU and device drivers during interrupt service routine or polling. The register
bits are not cleared when read. The user has to write “1” to clear.
TABLE 4-34:
Bit
BANK 18 INTERRUPT STATUS REGISTER (0X02)
Default Value
R/W
Description
0x0
RO
(W1C)
LCIS Link Change Interrupt Status
When this bit is set, it indicates that the link status has changed
from link up to link down, or link down to link up.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
RO
(W1C)
TXIS Transmit Status
When this bit is set, it indicates that the TXQ MAC has transmitted
at least a frame on the MAC interface and the QMU TXQ is ready
for new frames from the host.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
RXIS Receive Interrupt Status
When this bit is set, it indicates that the QMU RXQ has received a
frame from the MAC interface and the frame is ready for the host
CPU to process.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
15
14
0x0
13
0x0
RO
(W1C)
12
0x0
RO
11
0x0
RO
(W1C)
10
0x0
RO
0x1
RO
(W1C)
TXPSIE Transmit Process Stopped Status
When this bit is set, it indicates that the Transmit Process has
stopped.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
0x1
RO
(W1C)
RXPSIE Receive Process Stopped Status
When this bit is set, it indicates that the Receive Process has
stopped.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
7
0x0
RO
(W1C)
RXEFIE Receive Error Frame Interrupt Status
When this bit is set, it indicates that the Receive error frame status
has occurred.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
6-0
—
RO
9
8
DS00003459A-page 62
Reserved
RXOIS Receive Overrun Interrupt Status
When this bit is set, it indicates that the Receive Overrun status has
occurred.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
Reserved
Reserved
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 18 Receive Status Register (0x04): RXSR
This register indicates the status of the current received frame and mirrors the Receive Status word of the Receive
Frame in the RXQ.
TABLE 4-35:
Bit
BANK 18 RECEIVE STATUS REGISTER (0X04)
Default Value
R/W
Description
15
—
RO
RXFV Receive Frame Valid
When set, it indicates that the present frame in the receive packet
memory is valid. The status information currently in this location is
also valid.
When clear, it indicates that there is either no pending receive
frame or that the current frame is still in the process of receiving.
14 - 10
—
RO
Reserved
9-8
—
RO
RXSPN Receive Source Port Number
When bit is set, this field indicates the source port where the packet
was received. (Setting bit 9 = 0 and bit 8 = 1 indicates the packet
was received from port 1. Setting bit 9 = 1 and bit 8 = 0 indicates
that the packet was received from port 2. Valid port is either port 1
or port 2.
7
—
RO
RXBF Receive Broadcast Frame
When set, it indicates that this frame has a broadcast address.
6
—
RO
RXMF Receive Multicast Frame
When set, it indicates that this frame has a multicast address
(including the broadcast address).
5
—
RO
RXUF Receive Unicast Frame
When set, it indicates that this frame has a unicast address.
4
—
RO
Reserved
RO
RXFT Receive Frame Type
When set, it indicates that the frame is an Ethernet-type frame
(frame length is greater than 1500 bytes).
When clear, it indicate that the frame is an IEEE 802.3 frame.
This bit is not valid for runt frames.
RO
RXTL Receive Frame Too Long
When set, it indicates that the frame length exceeds the maximum
size of 1916 bytes. Frames that are too long are passed to the host
only if the pass bad frame bit is set (bit 9 in RXCR register).
Note: Frame too long is only a frame length indication and does not
cause any frame truncation.
RO
RXRF Receive Runt Frame
When set, it indicates that a frame was damaged by a collision or
premature termination before the collision window has passed.
Runt frames are passed to the host only if the pass bad frame bit is
set (bit 9 in RXCR register).
RO
RXCE Receive CRC Error
When set, it indicates that a CRC error has occurred on the current
received frame. A CRC error frame is passed to the host only if the
pass bad frame bit is set (bit 9 in RXCR register)
3
2
1
0
—
—
—
—
2020 Microchip Technology Inc.
DS00003459A-page 63
KSZ8842-16M/-32M
Bank 18 Receive Byte Count Register (0x06): RXBC
This register indicates the status of the current received frame and mirrors the Receive Byte Count word of the Receive
Frame in the RXQ.
TABLE 4-36:
BANK 18 RECEIVE BYTE COUNT REGISTER (0X06)
Bit
Default Value
R/W
Description
15 - 11
—
RO
Reserved
10 - 0
—
RO
RXBC Receive Byte Count
Receive byte count.
Bank 19 Multicast Table Register 0 (0x00): MTR0
The 64-bit multicast table is used for group address filtering. This value is defined as the six most significant bits from
CRC circuit calculation result that is based on 48-bit of DA input. The two most significant bits select one of the four
registers to be used, while the others determine which bit within the register.
TABLE 4-37:
Bit
15 - 0
BANK 19 MULTICAST TABLE REGISTER 0 (0X00)
Default Value
0x0000
R/W
Description
R/W
MTR0 Multicast Table 0
When the appropriate bit is set, if the packet received with DA
matches the CRC, the hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXRA) or receive multicast (RXRM) bit
is set in the RXCR, all multicast addresses are received regardless
of the multicast table value.
Bank 19 Multicast Table Register 1 (0x02): MTR1
TABLE 4-38:
Bit
15 - 0
BANK 19 MULTICAST TABLE REGISTER 1 (0X02)
Default Value
0x0000
R/W
Description
R/W
MTR0 Multicast Table 1
When the appropriate bit is set, if the packet received with DA
matches the CRC, the hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXRA) or receive multicast (RXRM) bit
is set in the RXCR, all multicast addresses are received regardless
of the multicast table value.
Bank 19 Multicast Table Register 2 (0x04): MTR2
TABLE 4-39:
Bit
15 - 0
BANK 19 MULTICAST TABLE REGISTER 2 (0X04)
Default Value
0x0000
DS00003459A-page 64
R/W
Description
R/W
MTR0 Multicast Table 2
When the appropriate bit is set, if the packet received with DA
matches the CRC, the hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXRA) or receive multicast (RXRM) bit
is set in the RXCR, all multicast addresses are received regardless
of the multicast table value.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 19 Multicast Table Register 3 (0x06): MTR3
TABLE 4-40:
Bit
BANK 19 MULTICAST TABLE REGISTER 3 (0X06)
Default Value
15 - 0
0x0000
R/W
Description
R/W
MTR0 Multicast Table 3
When the appropriate bit is set, if the packet received with DA
matches the CRC, the hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXRA) or receive multicast (RXRM) bit
is set in the RXCR, all multicast addresses are received regardless
of the multicast table value.
Banks 20 – 31: Reserved
Except Bank Select Register (0xE).
Bank 32 Switch ID and Enable Register (0x00): SIDER
This register contains the chip ID and the switch enable control.
TABLE 4-41:
BANK 32 CHIP ID AND ENABLE REGISTER (0X00)
Bit
Default Value
R/W
Description
15 - 8
0x88
RO
Family ID
Chip family ID
7-4
0x8
RO
Chip ID
0x8 is assigned to KSZ8842M
3-1
0x1
RO
Revision ID
0
0
R/W
Start Switch
1 = Start the chip.
0 = Switch is disabled.
Bank 32 Switch Global Control Register 1 (0x02): SGCR1
This register contains global control bits for the switch function.
TABLE 4-42:
SWITCH GLOBAL CONTROL REGISTER 1 (0X02): SGCR1
Bit
Default
15
0
Pass All Frames
RW 1 = Switch all packets including bad ones. Used solely for debugging purposes. Works in
conjunction with Sniffer mode only.
14
0
RW Reserved
1
IEEE 802.3x Transmit Direction Flow Control Enable
1 = Enables transmit direction flow control feature.
RW
0 = Disable transmit direction flow control feature. The switch will not generate any flow
control packets.
12
1
IEEE 802.3x Receive Direction Flow Control Enable
1 = Enables receive direction flow control feature.
RW
0 = Disable receive direction flow control feature. The switch will not react to any received
flow control packets.
11
0
Frame Length Field Check
RW 1 = Enable checking frame length field in the IEEE packets. If the actual length does not
match, the packet will be dropped (for Length/Type field < 1500).
10
1
Aging Enable
RW 1 = Enable aging function in the chip.
0 = Disable aging function in the chip.
13
R/W Description
2020 Microchip Technology Inc.
DS00003459A-page 65
KSZ8842-16M/-32M
TABLE 4-42:
SWITCH GLOBAL CONTROL REGISTER 1 (0X02): SGCR1 (CONTINUED)
Bit
Default
9
0
RW
8
0
Aggressive Back-Off Enable
RW 1 = Enable more aggressive back-off algorithm in half-duplex mode to enhance
performance. This is not an IEEE standard.
7-4
—
RW Reserved
0
Enable Flow Control when Exceeding Ingress Limit
1 = Flow control frame will be sent to link partner when exceeding the
RW
ingress rate limit.
0 = Frame will be dropped when exceeding the ingress rate limit.
4
1
Receive 2K Byte Packets Enable
1 = Enable packet length up to 2K bytes. While set, SGCR2
RW
bits[2,1] will have no effect.
0 = Discard packet if packet length is greater than 2000
bytes.
3
0x0
2-1
—
RW Reserved
0
Link Change Age
1 = Link change from “link” to “no link” will cause fast aging (
TXP1/TXM1, (see Figure 7-2)
0 = Normal operation
0
0
RO
Reserved
Bit Same As
—
Bank 47 PHY2 LinkMD Control/Status (0x04): P2VCT
This register contains the LinkMD control and status information of PHY 2.
TABLE 4-86:
Bit
BANK 47 PHY2 LINKMD CONTROL/STATUS (0X04): P2VCT
Default Value
R/W
Description
Bit Same As
0
R/W
(SelfClear)
Vct_enable
1 = Cable diagnostic test is enabled. It is self-cleared after
the VCT test is done.
0 = Indicates that the cable diagnostic test is completed
and the status information is valid for read.
Bank 51 0x00
bit 12
Bank 51 0x00
bit 14 - 13
Bank 51 0x00
bit 15
15
14 - 13
0x0
RO
Vct_result
00 = Normal condition.
01 = Open condition detected in the cable.
10 = Short condition detected in the cable.
11 = Cable diagnostic test failed.
12
—
RO
Vct 10M Short
1 = Less than 10m short.
11 - 9
0x0
RO
Reserved
8-0
0x000
RO
Vct_fault_count
Distance to the fault. The distance is approximately
0.4m*vct_fault_count.
—
Bank 51 0x00
bit 8 - 0
Bank 47 PHY2 Special Control/Status Register (0x06): P2PHYCTRL
This register contains the control and status information of PHY2.
TABLE 4-87:
BANK 47 PHY1 SPECIAL CONTROL/STATUS REGISTER (0X02): P1PHYCTRL
Bit
Default Value
R/W
Description
15 - 6
0x000
RO
Reserved
Bank 51 0x04
bit 13
Bank 51 0x04
bit 7
5
0
RO
Polarity Reverse (polrvs)
1 = Polarity is reversed.
0 = Polarity is not reversed.
4
0
RO
MDIX Status (mdix_st)
1 = MDI
0 = MDIX
2020 Microchip Technology Inc.
Bit Same As
—
DS00003459A-page 87
KSZ8842-16M/-32M
TABLE 4-87:
BANK 47 PHY1 SPECIAL CONTROL/STATUS REGISTER (0X02): P1PHYCTRL
Bit
Default Value
R/W
Description
Bit Same As
3
0
R/W
Force Link (force_lnk)
1 = Force link pass.
0 = Normal operation.
Bank 51 0x00
bit 11
2
1
R/W
Power Saving (pwrsave)
1 = Disable power saving.
0 = Enable power saving.
Bank 51 0x00
bit 10
Bank 51 0x00
bit 9
1
0
R/W
Remote (Near-end) Loopback (rlb)
1 = Perform remote loopback at Port 2’s (RXP2/RXM2 ->
TXP2/TXM2, (see Figure 7-2)
0 = Normal operation
0
0
RO
Reserved
—
Bank 48 Port 1 Control Register 1 (0x00): P1CR1
This register contains control bits for the switch Port 1 function.
TABLE 4-88:
PORT 1 CONTROL REGISTER 1 (0X00): P1CR1
Bit
Default
R/W
Description
15 - 8
0x00
RO
Reserved
7
0
R/W
Broadcast Storm Protection Enable
1 = Enable broadcast storm protection for ingress packets on Port 1.
0 = Disable broadcast storm protection.
6
0
R/W
Diffserv Priority Classification Enable
1 = Enable DiffServ priority classification for ingress packets on Port 1.
0 = Disable DiffServ function.
5
0
R/W
802.1p Priority Classification Enable
1 = Enable 802.1p priority classification for ingress packets on Port 1.
0 = Disable 802.1p.
R/W
Port-Based Priority Classification
00 = Ingress packets on Port 1 are classified as priority 0 queue if
“DiffServ” or “802.1p” classification is not enabled or fails to classify.
01 = Ingress packets on Port 1 are classified as priority 1 queue if
“DiffServ” or “802.1p” classification is not enabled or fails to classify.
10 = Ingress packets on Port 1 are classified as priority 2 queue if
“DiffServ” or “802.1p” classification is not enabled or fails to classify.
11 = Ingress packets on Port 1 are classified as priority 3 queue if
“Diffserv” or “802.1p” classification is not enabled or fails to classify.
Note: “DiffServ”, “802.1p” and port priority can be enabled at the same
time. The OR’ed result of 802.1p and DSCP overwrites the port priority.
RW
Tag Insertion
1 = When packets are output on Port 1, the switch adds 802.1p/q tags to
packets without 802.1p/q tags when received. The switch will not add
tags to packets already tagged. The tag inserted is the ingress port’s
“port VID”.
0 = Disable tag insertion.
RW
Tag Removal
1 = When packets are output on Port 1, the switch removes 802.1p/q
tags from packets with 802.1p/q tags when received. The switch will not
modify packets received without tags.
0 = Disable tag removal.
4-3
2
1
0x0
0
0
DS00003459A-page 88
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 4-88:
Bit
0
PORT 1 CONTROL REGISTER 1 (0X00): P1CR1 (CONTINUED)
Default
0
R/W
Description
RW
TX Multiple Queues Select Enable
1 = The Port 1 output queue is split into four priority queues (q0, q1, q2
and q3).
0 = Single output queue on Port 1. There is no priority differentiation
even though packets are classified into high or low priority.
Bank 48 Port 1 Control Register 2 (0x02): P1CR2
This register contains control bits for the switch function.
TABLE 4-89:
PORT 1 CONTROL REGISTER 2 (0X02): P1CR2
Bit
Default
R/W
Description
15
0
RO
Reserved
RW
Ingress VLAN Filtering
1 = The switch discards packets whose VID port membership in VLAN
table bits [18:16] does not include the ingress port VID.
0 = No ingress VLAN filtering.
RW
Discard Non PVID Packets
1 = The switch discards packets whose VID does not match the ingress
port default VID.
0 = No packets are discarded.
14
13
0
0
12
0
RW
Force Flow Control
1 = Always enable flow control on the port, regardless of auto-negotiation result.
0 = The flow control is enabled based on auto-negotiation result.
11
0
RW
Back Pressure Enable
1 = Enable port’s half-duplex back pressure.
0 = Disable port’s half-duplex back pressure.
10
1
RW
Transmit Enable
1 = Enable packet transmission on the port.
0 = Disable packet transmission on the port.
9
1
RW
Receive Enable
1 = Enable packet reception on the port.
0 = Disable packet reception on the port.
8
0
RW
Learning Disable
1 = Disable switch address learning capability.
0 = Enable switch address learning.
RW
Sniffer Port
1 = Port is designated as a sniffer port and transmits packets that are
monitored.
0 = Port is a normal port.
RW
Receive Sniff
1 = All packets received on the port are marked as “monitored packets”
and forwarded to the designated “sniffer port.”
0 = No receive monitoring.
7
6
0
0
5
0
RW
Transmit Sniff
1 = All packets transmitted on the port are marked as “monitored packets” and forwarded to the designated “sniffer port.”
0 = No transmit monitoring.
4
0
RO
Reserved
2020 Microchip Technology Inc.
DS00003459A-page 89
KSZ8842-16M/-32M
TABLE 4-89:
Bit
PORT 1 CONTROL REGISTER 2 (0X02): P1CR2 (CONTINUED)
Default
3
0
2-0
0X7
R/W
Description
RW
User Priority Ceiling
1 = If the packet’s “priority field” is greater than the “user priority field” in
the port VID control register bit[15:13], replace the packet’s “priority field”
with the “user priority field” in the port VID control register bit[15:13].
0 = Do not compare and replace the packet’s “priority field.”
RW
Port VLAN Membership
Define the port’s Port VLAN membership. Bit [2] stands for the host port,
bit [1] for Port 2, and bit [0] for Port 1. The port can only communicate
within the membership. A ‘1’ includes a port in the membership; a ‘0’
excludes a port from the membership.
Bank 48 Port 1 VID Control Register (0x04): P1VIDCR
This register contains the global per port control for the switch function.
TABLE 4-90:
PORT 1 VID CONTROL REGISTER (0X04): P1VIDCR
Bit
Default
R/W
Description
15 - 13
0x00
RW
Default Tag[15:13]
Port’s default tag, containing “User Priority Field” bits.
12
0
RW
Default Tag[12]
Port’s default tag, containing the CFI bit.
11 - 0
Note:
Default Tag[11:0]
Port’s default tag, containing the VID[11:0].
This VID Control register serves two purposes:
Associated with the ingress untagged packets, and used for egress tagging.
Default VID for the ingress untagged or null-VID-tagged packets, and used for address lookup.
0x001
RW
Bank 48 Port 1 Control Register 3 (0x06): P1CR3
This register contains control bits for the switch Port 1 function.
TABLE 4-91:
PORT 1 CONTROL REGISTER 3 (0X06): P1CR3
Bit
Default
R/W
Description
15 - 5
0x000
RO
Reserved
4
0
RO
Reserved
RW
Ingress Limit Mode
These bits determine what kinds of frames are limited and counted
against ingress rate limiting as follows:
00 = Limit and count all frames.
01 = Limit and count Broadcast, Multicast, and flooded Unicast frames.
10 = Limit and count Broadcast and Multicast frames only.
11 = Limit and count Broadcast frames only.
RW
Count Inter Frame Gap
Count IFG Bytes.
1 = Each frame’s minimum inter frame gap.
IFG bytes (12 per frame) are included in ingress and egress rate calculations.
0 = IFG bytes are not counted.
3-2
1
0x0
0
DS00003459A-page 90
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 4-91:
Bit
0
PORT 1 CONTROL REGISTER 3 (0X06): P1CR3 (CONTINUED)
Default
0
R/W
Description
RW
Count Preamble
Count preamble Bytes.
1 = Each frame’s preamble bytes (8 per frame) are included in ingress
and egress rate limiting calculations.
0 = Preamble bytes are not counted.
Bank 48 Port 1 Ingress Rate Control Register (0x08): P1IRCR
TABLE 4-92:
Bit
15 - 12
11 - 8
PORT 1 INGRESS RATE CONTROL REGISTER (0X08): P1IRCR
Default
0x0
0x0
2020 Microchip Technology Inc.
R/W
Description
RW
Ingress Pri3 Rate
Priority 3 frames will be discarded after the ingress rate selected as
shown below is reached or exceeded.
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Note: For 10 BT, rate settings above 10 Mbps are set to the default value
0000 (not limited).
RW
Ingress Pri2 Rate
Priority 2 frames will be discarded after the ingress rate selected as
shown below is reached or exceeded.
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Note: For 10BT, rate settings above 10Mbps are set to the default value
0000 (not limited).
DS00003459A-page 91
KSZ8842-16M/-32M
TABLE 4-92:
Bit
7-4
3-0
PORT 1 INGRESS RATE CONTROL REGISTER (0X08): P1IRCR
Default
0x0
0x0
DS00003459A-page 92
R/W
Description
RW
Ingress Pri1 Rate
Priority 1 frames will be discarded after the ingress rate selected as
shown below is reached or exceeded.
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Note: For 10 BT, rate settings above 10 Mbps are set to the default value
0000 (not limited).
RW
Ingress Pri0 Rate
Priority 0 frames will be discarded after the ingress rate selected as
shown below is reached or exceeded.
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Note: For 10 BT, rate settings above 10 Mbps are set to the default value
0000 (not limited).
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 48 Port 1 Egress Rate Control Register (0x0A): P1ERCR
TABLE 4-93:
Bit
15 - 12
11 - 8
PORT 1 EGRESS RATE CONTROL REGISTER (0X0A): P1ERCR
Default
0x0
0x0
2020 Microchip Technology Inc.
R/W
Description
RW
Egress Pri3 Rate
Egress data rate limit for priority 3 frames.
Output traffic from this priority queue is shaped according to the egress
rate selected below:
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Notes: For 10BT, rate settings above 10Mbps are set to the default value
0000 (not limited).
When multiple queue select enable is off (only 1 queue per port), rate
limiting applies only to priority 0 queue.
RW
Egress Pri2 Rate
Egress data rate limit for priority 2 frames.
Output traffic from this priority queue is shaped according to the egress
rate selected below:
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Notes: For 10BT, rate settings above 10Mbps are set to the default value
0000 (not limited).
When multiple queue select enable is off (only 1 queue per port), rate
limiting applies only to priority 0 queue.
DS00003459A-page 93
KSZ8842-16M/-32M
TABLE 4-93:
Bit
7-4
3-0
PORT 1 EGRESS RATE CONTROL REGISTER (0X0A): P1ERCR
Default
0x0
0x0
DS00003459A-page 94
R/W
Description
RW
Egress Pri1 Rate
Egress data rate limit for priority 1 frames.
Output traffic from this priority queue is shaped according to the egress
rate selected below:
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Notes: For 10BT, rate settings above 10Mbps are set to the default value
0000 (not limited).
When multiple queue select enable is off (only 1 queue per port), rate
limiting applies only to priority 0 queue.
RW
Egress Pri0 Rate
Egress data rate limit for priority 0 frames.
Output traffic from this priority queue is shaped according to the egress
rate selected below:
0000 = Not limited (default)
0001 = 64 Kbps
0010 = 128 Kbps
0011 = 256 Kbps
0100 = 512 Kbps
0101 = 1 Mbps
0110 = 2 Mbps
0111 = 4 Mbps
1000 = 8 Mbps
1001 = 16 Mbps
1010 = 32 Mbps
1011 = 48 Mbps
1100 = 64 Mbps
1101 = 72 Mbps
1110 = 80 Mbps
1111 = 88 Mbps
Notes: For 10BT, rate settings above 10Mbps are set to the default value
0000 (not limited).
When multiple queue select enable is off (only 1 queue per port), rate
limiting applies only to priority 0 queue.
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 49 Port 1 PHY Special Control/Status, LinkMD (0x00): P1SCSLMD
TABLE 4-94:
PORT 1 PHY SPECIAL CONTROL/STATUS, LINKMD (0X00): P1SCSLMD
Bit
Default
R/W
Description
15
0
RO
Vct_10m_short
1 = Less than 10 meter short.
Bank 47 0x00 bit 12
RO
Vct_result
VCT result.
00 = Normal condition.
01 = Open condition has been detected in cable.
10 = Short condition has been detected in cable.
11 = Cable diagnostic test is failed.
Bank 47 0x00 bit 14-13
R/W
(SC)
Vct_en
Vct enable.
1 = The cable diagnostic test is enabled. It is selfcleared after the VCT test is done.
0 = Indicates the cable diagnostic test is completed
and the status information is valid for read.
Bank 47 0x00 bit 15
RW
Force_Link
Force link.
1 = Force link pass.
0 = Normal operation.
Bank 47 0x02 bit 3
RW
pwrsave
Power-saving.
1 = Disable power saving.
0 = Enable power saving.
Bank 47 0x02 bit 2
Bank 47 0x02 bit 1
—
14 - 13
0x0
12
0
11
0
10
1
9
0
RW
Remote (Near-End) Loopback
1 = Perform remote loopback at Port 1's PHY
(RXP1/RXM1 −> TXP1/TXM1, (see Figure 7-2)
0 = Normal operation
8-0
0x000
RO
Reserved
Bit Same As
Bank 49 Port 1 Control Register 4 (0x02): P1CR4
This register contains the global per port control for the switch function.
TABLE 4-95:
Bit
PORT 1 CONTROL REGISTER 4 (0X02): P1CR4
Default
R/W
Description
Bit Same As:
Bank 45 0x00 bit 0
15
0
RW
LED Off
1 = Turn off all of the port 1 LEDs (P1LED3, P1LED2,
P1LED1, P1LED0). These pins are driven high if this bit
is set to one.
0 = normal operation.
14
0
RW
Txids
1 = disable the port’s transmitter.
0 = normal operation.
Bank 45 0x00 bit 1
13
0
RW
Restart Auto-Negotiation
1 = Restart auto-negotiation.
0 = Normal operation.
Bank 45 0x00 bit 9
12
0
RW
Reserved
Bank 45 0x00 bit 2
11
0
RW
Power Down
1 = Power down.
0 = Normal operation.
Bank 45 0x00 bit 11
2020 Microchip Technology Inc.
DS00003459A-page 95
KSZ8842-16M/-32M
TABLE 4-95:
PORT 1 CONTROL REGISTER 4 (0X02): P1CR4
Bit
Default
R/W
Description
Bit Same As:
10
0
RW
Disable Auto MDI/MDI-X
1 = Disable Auto-MDI/MDI-X function.
0 = Enable Auto-MDI/MDI-X function.
Bank 45 0x00 bit 3
RW
Force MDI-X
1 = If Auto-MDI/MDI-X is disabled, force PHY into MDI-X
Bank 45 0x00 bit 4
mode.
0 = Do not force PHY into MDI-X mode.
RW
Far-End Loopback
1 = Perform loopback, as indicated:
Start: RXP2/RXM2 (Port 2).
Loopback: PMD/PMA of Port 1’s PHY.
End: TXP2/TXM2 (Port 2).
0 = Normal operation.
Bank 45 0x00 bit 14
Bank 45 0x00 bit 12
Bank 45 0x00 bit 13
9
8
0
0
7
1
RW
Auto-Negotiation Enable
1 = Auto-negotiation is enabled.
0 = Disable auto-negotiation, speed, and duplex are
decided by bits [6:5] of the same register.
6
1
RW
Force Speed
1 = Force 100BT if auto-negotiation is disabled (bit [7]).
0 = Force 10BT if auto-negotiation is disabled (bit [7]).
RW
Force Duplex
1 = Force full-duplex if auto-negotiation is disabled.
0 = Force half-duplex if auto-negotiation is disabled.
Bank 45 0x00 bit 8
This bit also determines duplex if auto-negotiation is
enabled but fails. When AN is enabled, this bit should be
set to zero.
RW
Advertised Flow Control Capability
1 = Advertise flow control (pause) capability.
0 = Suppress flow control (pause) capability from transmission to link partner.
RW
Advertised 100BT Full-Duplex Capability
1 = Advertise 100BT full-duplex capability.
Bank 45 0x08 bit 8
0 = Suppress 100BT full-duplex capability from transmission to link partner.
RW
Advertised 100BT Half-Duplex Capability
1 = Advertise 100BT half-duplex capability.
0 = Suppress 100BT half-duplex capability from transmission to link partner.
Bank 45 0x08 bit 7
RW
Advertised 10BT Full-Duplex Capability
1 = Advertise 10BT full-duplex capability.
0 = Suppress 10BT full-duplex capability from transmission to link partner.
Bank 45 0x08 bit 6
RW
Advertised 10BT Half-Duplex Capability
1 = Advertise 10BT half-duplex capability.
Bank 45 0x08 bit 5
0 = Suppress 10BT half-duplex capability from transmission to link partner.
5
4
3
2
1
0
1
1
1
1
1
1
DS00003459A-page 96
Bank 45 0x08 bit 10
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 49 Port 1 Status Register (0x04): P1SR
This register contains the global per port status for the switch function.
TABLE 4-96:
PORT 1 STATUS REGISTER (0X04): P1SR
Bit
Default
R/W
Description
Bit Same As:
15
1
RW
HP_MDI-X
1 = HP Auto-MDI-X mode.
0 = Microchip Auto-MDI-X mode.
Bank 45 0x00 bit 5
14
0
RO
Reserved
—
Bank 47 0x02 bit 5
13
0
RO
Polarity Reverse
1 = Polarity is reversed.
0 = Polarity is not reversed.
12
0
RO
Receive Flow Control Enable
1 = receive flow control feature is active.
0 = receive flow control feature is inactive.
—
11
0
RO
Transmit Flow Control Enable
1 = transmit flow control feature is active.
0 = transmit flow control feature is inactive.
—
10
0
RO
Operation Speed
1 = Link speed is 100 Mbps.
0 = Link speed is 10 Mbps.
—
9
0
RO
Operation Duplex
1 = Link duplex is full.
0 = Link duplex is half.
—
8
0
RO
Reserved
Bank 45 0x02 bit 4
7
0
RO
MDI-X Status
0 = MDI.
1 = MDI-X
Bank 47 0x02 bit 4
6
0
RO
AN Done
1 = AN done.
0 = AN not done.
Bank 45 0x02 bit 5
5
0
RO
Link Good
1 = Link good.
0 = Link not good.
Bank 45 0x02 bit 2
4
0
RO
Partner Flow Control Capability
1 = Link partner flow control (pause) capable.
0 = Link partner not flow control (pause) capable.
Bank 45 0x0A bit 10
3
0
RO
Partner 100BT Full-Duplex Capability
1 = Link partner 100BT full-duplex capable.
0 = Link partner not 100BT full-duplex capable.
Bank 45 0x0A bit 8
2
0
RO
Partner 100BT Half-Duplex Capability
1 = Link partner 100BT half-duplex capable.
0 = Link partner not 100BT half-duplex capable.
Bank 45 0x0A bit 7
1
0
RO
Partner 10BT Full-Duplex Capability
1 = Link partner 10BT full-duplex capable.
0 = Link partner not 10BT full-duplex capable.
Bank 45 0x0A bit 6
0
0
RO
Partner 10BT Half-Duplex Capability
1 = Link partner 10BT half-duplex capable.
0 = Link partner not 10BT half-duplex capable.
Bank 45 0x0A bit 5
Bank 50 Port 2 Control Register 1 (0x00): P2CR1
This register contains the global per port control for the switch function. See description in P1CR1, Bank 48 (0x00)
2020 Microchip Technology Inc.
DS00003459A-page 97
KSZ8842-16M/-32M
Bank 50 Port 2 Control Register 2 (0x02): P2CR2
This register contains the global per port control for the switch function. See description in P1CR2, Bank 48 (0x02)
Bank 50 Port 2 VID Control Register (0x04): P2VIDCR
This register contains the global per port control for the switch function. See description in P1VIDCR, Bank 48 (0x04)
Bank 50 Port 2 Control Register 3 (0x06): P2CR3
This register contains the global per port control for the switch function. See description in P1CR3, Bank 48 (0x06)
Bank 50 Port 2 Ingress Rate Control Register (0x08): P2IRCR
This register contains per port ingress rate control. See description in P1IRCR, Bank 48 (0x08)
Bank 50 Port 2 Egress Rate Control Register (0x0A): P2ERCR
This register contains per port egress rate control. See description in P1ERCR, Bank 48 (0x0A)
Bank 51 Port 2 PHY Special Control/Status, LinkMD (0x00): P2SCSLMD
TABLE 4-97:
PORT 2 PHY SPECIAL CONTROL/STATUS, LINKMD (0X00): P2SCSLMD
Bit
Default
R/W
Description
15
0
RO
Vct_10m_Short
1 = Less than 10 meter short.
Bank 47 0x04 bit 12
RO
Vct_Result
00 = Normal condition.
01 = Open condition has been detected in cable.
10 = Short condition has been detected in cable.
11 = Cable diagnostic test has failed.
Bank 47 0x04 bit 14-13
14 - 13
12
11
10
0x0
0
0
1
Bit Same As
Vct_Enable
1 = Cable diagnostic test is enabled. It is self-cleared
RW/SC after the CDT test is done.
0 = Indicates that the cable diagnostic test is completed and the status information is valid for reading.
Bank 47 0x04 bit 15
RW
Force_Link
Force link.
1 = Force link pass.
0 = Normal operation.
Bank 47 0x06 bit 3
RW
Pwrsave
Power-saving.
1 = disable power saving.
0 = enable power saving.
Bank 47 0x06 bit 2
9
0
RW
Remote (Near-End) Loopback
1 = Perform remote loopback at Port 2's PHY (RXP2/
Bank 47 0x06 bit 1
RXM2 −> TXP2/TXM2, (see Figure 7-2)
0 = Normal operation
8-0
0x000
RO
Vct_Fault_Count
Distance to the fault. It’s approximately 0.4m*CDTFault_Count.
DS00003459A-page 98
Bank 47 0x04 bit 8-0
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
Bank 51 Port 2 Control Register 4 (0x02): P2CR4
This register contains the global per port control for the switch function.
TABLE 4-98:
Bit
PORT 2 CONTROL REGISTER 4 (0X02): P2CR4
Default
R/W
Description
Bit Same As:
Bank 46 0x00 bit 0
15
0
RW
LED Off
1 = Turn off all of the port 2 LEDs (P2LED3, P2LED2,
P2LED1, P2LED0). These pins are driven high if this bit
is set to one.
0 = Normal operation.
14
0
RW
Txids
1 = Disable the port’s transmitter.
0 = Normal operation.
Bank 46 0x00 bit 1
13
0
RW
Restart Auto-Negotiation (Note 1)
1 = Restart auto-negotiation.
0 = Normal operation.
Bank 46 0x00 bit 9
12
0
RO
Reserved
Bank 46 0x00 bit 2
11
0
RW
Power Down
1 = Power down.
0 = Normal operation.
Bank 46 0x00 bit 11
10
0
RW
Disable Auto MDI/MDI-X
1 = Disable Auto-MDI/MDI-X function.
0 = Enable Auto-MDI/MDI-X function.
Bank 46 0x00 bit 3
RW
Force MDI-X
1 = If Auto-MDI/MDI-X is disabled, force PHY into MDI-X
Bank 46 0x00 bit 4
mode.
0 = Do not force PHY into MDI-X mode.
RW
Far-End Loopback
1 = Perform loopback, as indicated:
Start: RXP2/RXM2 (Port 2).
Loopback: PMD/PMA of Port 1’s PHY.
End: TXP2/TXM2 (Port 2).
0 = Normal operation.
Bank 46 0x00 bit 14
Bank 46 0x00 bit 12
Bank 46 0x00 bit 13
9
8
0
0
7
1
RW
Auto-Negotiation Enable
1 = Auto-negotiation is enabled.
0 = Disable auto-negotiation, speed, and duplex are
decided by bits [6:5] of the same register.
6
0
RW
Force Speed
1 = Force 100BT if auto-negotiation is disabled (bit [7]).
0 = Force 10BT if auto-negotiation is disabled (bit [7]).
RW
Force Duplex
1 = Force full-duplex if auto-negotiation is disabled.
0 = Force half-duplex if auto-negotiation is disabled.
Bank 46 0x00 bit 8
This bit also determines duplex if auto-negotiation is
enabled but fails. When AN is enabled, this bit should be
set to zero.
RW
Advertised Flow Control Capability
1 = Advertise flow control (pause) capability.
0 = Suppress flow control (pause) capability from transmission to link partner.
RW
Advertised 100BT Full-Duplex Capability
1 = Advertise 100BT full-duplex capability.
Bank 46 0x08 bit 8
0 = Suppress 100BT full-duplex capability from transmission to link partner.
5
4
3
1
1
1
2020 Microchip Technology Inc.
Bank 46 0x08 bit 10
DS00003459A-page 99
KSZ8842-16M/-32M
TABLE 4-98:
Bit
PORT 2 CONTROL REGISTER 4 (0X02): P2CR4
Default
2
1
1
1
0
1
R/W
Description
Bit Same As:
RW
Advertised 100BT Half-Duplex Capability
1 = Advertise 100BT half-duplex capability.
0 = Suppress 100BT half-duplex capability from transmission to link partner.
Bank 46 0x08 bit 7
RW
Advertised 10BT Full-Duplex Capability
1 = Advertise 10BT full-duplex capability.
0 = Suppress 10BT full-duplex capability from transmission to link partner.
Bank 46 0x08 bit 6
RW
Advertised 10BT Half-Duplex Capability
1 = Advertise 10BT half-duplex capability.
Bank 46 0x08 bit 5
0 = Suppress 10BT half-duplex capability from transmission to link partner.
Bank 51 Port 2 Status Register (0x04): P2SR
This register contains the global per port status for the chip function.
TABLE 4-99:
PORT 2 STATUS REGISTER (0X04)
Bit
Default Value
R/W
15
1
R/W
HP_mdix
1 = HP Auto MDI-X mode.
0 = Microchip Auto MDI-X mode.
14
0
RO
Reserved
13
0
RO
Polarity Reverse
1 = Polarity is reversed.
0 = Polarity is not reversed.
12
0
RO
Receive Flow Control Enable
1 = Receive flow control feature is active.
0 = Receive flow control feature is inactive.
—
11
0
RO
Transmit Flow Control Enable
1 = Transmit flow control feature is active.
0 = Transmit flow control feature is inactive.
—
10
0
RO
Operation Speed
1 = Link speed is 100 Mbps.
0 = Link speed is 10 Mbps.
—
9
0
RO
Operation Duplex
1 = Link duplex is full.
0 = Link duplex is half.
—
8
0
RO
Reserved
Bank 46 0x02
bit 4
7
0
RO
MDI-X Status
1 = MDI.
0 = MDI-X.
Bank 47 0x06
bit 4
6
0
RO
AN Done
1 = AN done.
0 = AN not done.
Bank 46 0x02
bit 5
5
0
RO
Link Good
1 = Link good.
0 = Link not good.
Bank 46 0x02
bit 2
DS00003459A-page 100
Description
Same Bit As
Bank 46 0x00
bit 5
—
Bank 47 0x06
bit 5
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
TABLE 4-99:
PORT 2 STATUS REGISTER (0X04) (CONTINUED)
Bit
Default Value
R/W
Description
Same Bit As
4
0
RO
Partner flow control capability
1 = Link partner flow control (pause) capable.
0 = Link partner not flow control (pause) capable.
Bank 46 0x0A
bit 10
3
0
RO
Partner 100BT full-duplex capability
1 = Link partner 100BT full-duplex capable.
0 = Link partner not 100BT full-duplex capable.
Bank 46 0x0A
bit 8
2
0
RO
Partner 100BT half-duplex capability
1 = Link partner 100BT half-duplex capable.
0 = Link partner not 100BT half-duplex capable.
Bank 46 0x0A
bit 7
1
0
RO
Partner 10BT full-duplex capability
1 = Link partner 10BT full-duplex capable.
0 = Link partner not 10BT full-duplex capable.
Bank 46 0x0A
bit 6
0
0
RO
Partner 10BT half-duplex capability
1 = Link partner 10BT half-duplex capable.
0 = Link partner not 10BT half-duplex capable.
Bank 46 0x0A
bit 5
Bank 52 Host Port Control Register 1 (0x00): P3CR1
This register contains the global per port control for the switch function. See description in P1CR1, Bank 48 (0x00)
Bank 52 Host Port Control Register 1 (0x02): P3CR2
This register contains control bits for the switch Port 3 function.
TABLE 4-100: PORT 3 CONTROL REGISTER 2 (0X02): P3CR2
Bit
Default
R/W
Description
15
0
RO
Reserved
RW
Ingress VLAN Filtering
1 = The switch discards packets whose VID port membership in VLAN
table bits [18:16] does not include the ingress port VID.
0 = No ingress VLAN filtering.
14
0
13
0
RW
Discard Non PVID Packets
1 = The switch discards packets whose VID does not match the ingress
port default VID.
0 = No packets are discarded.
12
0
RO
Reserved
11
0
RO
Reserved
10
1
RW
Transmit Enable
1 = Enable packet transmission on the port.
0 = Disable packet transmission on the port.
9
1
RW
Receive Enable
1 = Enable packet reception on the port.
0 = Disable packet reception on the port.
8
0
RW
Learning Disable
1 = Disable switch address learning capability.
0 = Enable switch address learning.
RW
Sniffer Port
1 = Port is designated as a sniffer port and transmits packets that are
monitored.
0 = Port is a normal port.
7
0
2020 Microchip Technology Inc.
DS00003459A-page 101
KSZ8842-16M/-32M
TABLE 4-100: PORT 3 CONTROL REGISTER 2 (0X02): P3CR2 (CONTINUED)
Bit
6
Default
0
R/W
Description
RW
Receive Sniff
1 = All packets received on the port are marked as “monitored packets”
and forwarded to the designated “sniffer port.”
0 = No receive monitoring.
5
0
RW
Transmit Sniff
1 = All packets transmitted on the port are marked as “monitored packets”
and forwarded to the designated “sniffer port.”
0 = No transmit monitoring.
4
0
RO
Reserved
RW
User Priority Ceiling
1 = if the packet’s “user priority field” is greater than the “user priority
field” in the port default tag register, replace the packet’s “user priority
field” with the “user priority field” in the port default tag register.
0 = do not compare and replace the packet’s ‘user priority field.”
RW
Port VLAN Membership
Define the port’s Port VLAN membership. Bit [2] stands for the host port,
bit [1] for Port 2, and bit [0] for Port 1. The port can only communicate
within the membership. A ‘1’ includes a port in the membership; a ‘0’
excludes a port from the membership.
3
2-0
0
0x7
Bank 52 Host Port VID Control Register (0x04): P3VIDCR
This register contains the global per port control for the switch function. See description in P1VIDCR, Bank 48 (0x04)
Bank 52 Host Port Control Register 3 (0x06): P3CR3
This register contains the global per port control for the switch function. See description in P1CR3, Bank 48 (0x06)
Bank 52 Host Port Ingress Rate Control Register (0x08): P3IRCR
This register contains per port ingress rate control. See description in P1IRCR, Bank 48 (0x08)
Bank 52 Host Port Egress Rate Control Register (0x0A): P3ERCR
This register contains per port egress rate control. See description in P1ERCR, Bank 48 (0x0A)
Banks 53 – 63: Reserved
Except Bank Select Register (0xE)
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4.4
Management Information Base (MIB) Counters
The KSZ8842M provides 34 MIB counters for each port. These counters are used to monitor the port activity for network
management. The MIB counters are formatted “per port” as shown in Table 4-101 and “all ports dropped packet” as
shown in Table 4-103.
TABLE 4-101: FORMAT OF PER PORT MIB COUNTERS
Bit
Name
R/W
Description
Default
31
Overflow
RO
1 = Counter overflow.
0 = No counter overflow.
0
30
Count Valid
RO
1 = Counter value is valid.
0 = Counter value is not valid.
0
Counter Values
RO
Counter value (read clear)
29 - 0
0x00000000
“Per Port” MIB counters are read using indirect memory access. The base address offsets and address ranges for both
Ethernet ports are:
Port 1, base address is 0x00 and range is from 0x00 to 0x1F.
Port 2, base address is 0x20 and range is from 0x20 to 0x3F.
Per port MIB counters are read using indirect access control register in IACR, Bank 42 (0x00) and indirect access data
registers in IADR4[15:0], IADR5[31:16]. Table 4-102 shows the port 1 MIB counters address memory offset.
TABLE 4-102: PORT 1 MIB COUNTERS INDIRECT MEMORY OFFSETS
Offset
Counter Name
Description
0x0
RxLoPriorityByte
Rx lo-priority (default) octet count including bad packets
0x1
Reserved
Reserved
0x2
RxUndersizePkt
Rx undersize packets w/ good CRC
0x3
RxFragments
Rx fragment packets w/ bad CRC, symbol errors or alignment errors
0x4
RxOversize
Rx oversize packets w/ good CRC (max: 1536 bytes)
0x5
RxJabbers
Rx packets longer than 1536 bytes w/ either CRC errors, alignment
errors, or symbol errors
0x6
RxSymbolError
Rx packets w/ invalid data symbol and legal packet size.
0x7
RxCRCError
Rx packets within (64,1916) bytes w/ an integral number of bytes and
a bad CRC
0x8
RxAlignmentError
Rx packets within (64,1916) bytes w/ a non-integral number of bytes
and a bad CRC
0x9
RxControl8808Pkts
Number of MAC control frames received by a port with 88-08h in
EtherType field
0xA
RxPausePkts
Number of PAUSE frames received by a port. PAUSE frame is qualified with EtherType (88-08h), DA, control opcode (00-01), data length
(64B min), and a valid CRC
0xB
RxBroadcast
Rx good broadcast packets (not including error broadcast packets or
valid multicast packets)
0xC
RxMulticast
Rx good multicast packets (not including MAC control frames, error
multicast packets or valid broadcast packets)
0xD
RxUnicast
Rx good unicast packets
0xE
Rx64Octets
Total Rx packets (bad packets included) that were 64 octets in length
0xF
Rx65to127Octets
Total Rx packets (bad packets included) that are between 65 and 127
octets in length
0x10
Rx128to255Octets
Total Rx packets (bad packets included) that are between 128 and
255 octets in length
0x11
Rx256to511Octets
Total Rx packets (bad packets included) that are between 256 and
511 octets in length
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TABLE 4-102: PORT 1 MIB COUNTERS INDIRECT MEMORY OFFSETS (CONTINUED)
Offset
Counter Name
Description
0x12
Rx512to1023Octets
Total Rx packets (bad packets included) that are between 512 and
1023 octets in length
0x13
Rx1024to1522Octets
Total Rx packets (bad packets included) that are between 1024 and
1916 octets in length
0x14
TxLoPriorityByte
Tx lo-priority good octet count, including PAUSE packets
0x15
Reserved
Reserved
0x16
TxLateCollision
The number of times a collision is detected later than 512 bit-times
into the Tx of a packet
0x17
TxPausePkts
Number of PAUSE frames transmitted by a port
0x18
TxBroadcastPkts
Tx good broadcast packets (not including error broadcast or valid
multicast packets)
0x19
TxMulticastPkts
Tx good multicast packets (not including error multicast packets or
valid broadcast packets)
0x1A
TxUnicastPkts
Tx good unicast packets
0x1B
TxDeferred
Tx packets by a port for which the 1st Tx attempt is delayed due to
the busy medium
0x1C
TxTotalCollision
Tx total collision, half-duplex only
0x1D
TxExcessiveCollision
A count of frames for which Tx fails due to excessive collisions
0x1E
TxSingleCollision
Successfully Tx frames on a port for which Tx is inhibited by exactly
one collision
0x1F
TxMultipleCollision
Successfully Tx frames on a port for which Tx is inhibited by more
than one collision
TABLE 4-103: ALL PORTS DROPPED PACKET” MIB COUNTERS FORMAT
Bit
Default
R/W
Description
30 - 16
—
RO
Reserved
15 - 0
Note:
0x0000
RO
Counter value
“All Ports Dropped Packet” MIB Counters do not indicate overflow or validity; therefore, the application must
keep track of overflow and valid conditions.
“All Ports Dropped Packet” MIB counters are read using indirect memory access. The address offsets for these counters
are shown in Table 4-104.
TABLE 4-104: “ALL PORTS DROPPED PACKET” MIB COUNTERS INDIRECT MEMORY OFFSETS
Offset
Counter Name
Description
0x100
Port1 TX Drop Packets
TX packets dropped due to lack of resources
0x101
Port2 TX Drop Packets
TX packets dropped due to lack of resources
0x103
Port1 RX Drop Packets
RX packets dropped due to lack of resources
0x104
Port2 RX Drop Packets
RX packets dropped due to lack of resources
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Examples:
1.
MIB Counter Read (read port 1 “Rx64Octets” counter at indirect address offset 0x0E)
Write to reg. IACR with 0x1C0E (set indirect address and trigger a read MIB counters operation)
Then
Read reg. IADR5 (MIB counter value 31-16) // If bit 31 = 1, there was a counter overflow
// If bit 30 = 0, restart (re-read) from this register
Read reg. IADR4 (MIB counter value 15-0)
2.
MIB Counter Read (read port 2 “Rx64Octets” counter at indirect address offset 0x2E)
Write to reg. IACR with 0x1C2E (set indirect address and trigger a read MIB counters operation)
Then
Read reg. IADR5 (MIB counter value 31-16) // If bit 31 = 1, there was a counter overflow
// If bit 30 = 0, restart (re-read) from this register
Read reg. IADR4 (MIB counter value 15-0)
3.
MIB Counter Read (read “Port1 TX Drop Packets” counter at indirect address offset 0x100)
Write to reg. IACR with 0x1d00 (set indirect address and trigger a read MIB counters operation)
Then
Read reg. IADR4 (MIB counter value 15-0)
4.4.1
ADDITIONAL MIB INFORMATION
Per Port MIB counters are designed as “read clear”. That is, these counters will be cleared after they are read.
All Ports Dropped Packet MIB counters are not cleared after they are accessed. The application needs to keep track of
overflow and valid conditions on these counters.
4.5
Static MAC Address Table
The KSZ8842M supports both a static and a dynamic MAC address table. In response to a Destination Address (DA)
look up, The KSZ8842M searches both tables to make a packet forwarding decision. In response to a Source Address
(SA) look up, only the dynamic table is searched for aging, migration and learning purposes.
The static DA look up result takes precedence over the dynamic DA look up result. If there is a DA match in both tables,
the result from the static table is used. These entries in the static table will not be aged out by the KSZ8842M.
TABLE 4-105: STATIC MAC TABLE FORMAT (8 ENTRIES)
Bit
Default Value
R/W
Description
57 - 54
0000
RW
FID
Filter VLAN ID − identifies one of the 16 active VLANs.
53
0
R/W
Use FID
1 = Specifies the use of FID+MAC for static table look up.
0 = Specifies only the use of MAC for static table look up.
R/W
Override
1 = Overrides the port setting transmit enable = “0” or receive enable
= “0” setting.
0 = Specifies no override.
R/W
Valid
1 = Specifies that this entry is valid, and the look up result will be
used.
0 = Specifies that this entry is not valid.
52
51
0
0
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TABLE 4-105: STATIC MAC TABLE FORMAT (8 ENTRIES)
Bit
Default Value
R/W
Description
50 - 48
000
R/W
Forwarding Ports
These 3 bits control the forwarding port(s):
000 = No forward.
001 = Forward to Port 1.
010 = Forward to Port 2.
100 = Forward to Port 3.
011 = Forward to Port 1 and Port 2.
110 = Forward to Port 2 and Port 3.
101 = Forward to Port 1 and Port 3.
111 = Broadcasting (excluding the ingress port).
47 - 0
0
R/W
MAC Address
48−bit MAC Address
Static MAC Table Lookup Examples:
Static Address Table Read (read the second entry at indirect address offset 0x01)
Write to Reg. IACR with 0x1001 (set indirect address and trigger a read static MAC table operation)
Then:
Read Reg. IADR3 (static MAC table bits [57:48])
Read Reg. IADR2 (static MAC table bits [47:32])
Read Reg. IADR5 (static MAC table bits [31:16])
Read Reg. IADR4 (static MAC table bits [15:0])
Static Address Table Write (write the eighth entry at indirect address offset 0x07)
Write to Reg. IADR3 (static MAC table bits [57:48])
Write to Reg. IADR2 (static MAC table bits [47:32])
Write to Reg. IADR5 (static MAC table bits [31:16])
Write to Reg. IADR4 (static MAC table bits [15:0])
Write to Reg. IACR with 0x0007 (set indirect address and trigger a write static MAC table operation)
4.6
Dynamic MAC Address Table
The Dynamic MAC Address (Table 4-106) is a read-only table.
TABLE 4-106: DYNAMIC MAC ADDRESS TABLE FORMAT (1024 ENTRIES)
Bit
Default
R/W
Description
71
—
RO
Data Not Ready
1 = Specifies that the entry is not ready, continue retrying until bit is
set to “0”.
0 = Specifies that the entry is ready.
70 - 67
—
RO
Reserved
66
1
RO
MAC Empty
1 = Specifies that there is no valid entry in the table
0 = Specifies that there are valid entries in the table
RO
Number of Valid Entries
Indicates how many valid entries in the table.
0x3ff means 1K entries.
0x001 means 2 entries.
0x000 and bit [66] = “0” means 1 entry.
0x000 and bit [66] = “1” means 0 entry.
65 - 56
0x000
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TABLE 4-106: DYNAMIC MAC ADDRESS TABLE FORMAT (1024 ENTRIES) (CONTINUED)
Bit
Default
R/W
Description
55 - 54
—
RO
Timestamp
Specifies the 2−bit counter for internal aging.
53 - 52
00
RO
Source Port
Identifies the source port where FID+MAC is learned:
00 = Port 1
01 = Port 2
10 = Port 3 (host port)
51 - 48
0x0
RO
FID
Specifies the filter ID.
47 - 0
0x0000_0000_0000
RO
MAC Address
Specifies the 48−bit MAC Address.
Dynamic MAC Address Lookup Example:
1.
Dynamic MAC Address Table Read (read the first entry at indirect address offset 0 and retrieve the MAC table
size)
Write to Reg. IACR with 0x1800 (set indirect address and trigger a read dynamic MAC table operation)
Then:
Read Reg. IADR1 (dynamic MAC table bits [71:64]) // If bit [71] = “1”, restart (re-read) from this register
Read Reg. IADR3 (dynamic MAC table bits [63:48])
Read Reg. IADR2 (dynamic MAC table bits [47:32])
Read Reg. IADR5 (dynamic MAC table bits [31:16])
Read Reg. IADR4 (dynamic MAC table bits [15:0])
4.7
VLAN Table
The KSZ8842M uses the VLAN table to perform look-ups. If 802.1Q VLAN mode is enabled (SGCR2[15]), this table will
be used to retrieve the VLAN information that is associated with the ingress packet. This information includes FID (Filter
ID), VID (VLAN ID), and VLAN membership as described in Table 4-107:
TABLE 4-107: VLAN TABLE FORMAT (16 ENTRIES)
Bit
Default
R/W
Description
19
1
RW
Valid
1 = Specifies that this entry is valid, the look up result will be used.
0 = Specifies that this entry is not valid.
R/W
Membership
Specifies which ports are members of the VLAN. If a DA look up
fails (no match in both static and dynamic tables), the packet associated with this VLAN will be forwarded to ports specified in this
field. For example: “101” means Port 3 and Port 1 are in this VLAN.
18 - 16
111
15 - 12
0x0
R/W
FID
Specifies the Filter ID. The KSZ8842 supports 16 active VLANs
represented by these four bit fields. The FID is the mapped ID. If
802.1Q VLAN is enabled, the look up will be based on FID+DA and
FID+SA.
11 - 0
0x001
R/W
VID
Specifies the IEEE 802.1Q 12 bits VLAN ID.
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If 802.1Q VLAN mode is enabled, then KSZ8842 will assign a VID to every ingress packet. If the packet is untagged or
tagged with a null VID, then the packet is assigned with the default port VID of the ingress port. If the packet is tagged
with non-null VID, then VID in the tag will be used. The look up process will start from the VLAN table look up. If the VID
is not valid, then packet will be dropped and no address learning will take place. If the VID is valid, then FID is retrieved.
The FID+DA and FID+SA lookups are performed. The FID+DA look up determines the forwarding ports. If FID+DA fails,
then the packet will be broadcast to all the members (excluding the ingress port) of the VLAN. If FID+SA fails, then the
FID+SA will be learned.
VLAN Table Lookup Examples:
1.
VLAN Table Read (read the third entry, at the indirect address offset 0x02)
Write to Reg. IACR with 0x1402 (set indirect address and trigger a read VLAN table operation)
Then:
Read Reg. IADR5 (VLAN table bits [19:16])
Read Reg. IADR4 (VLAN table bits [15:0])
2.
VLAN Table Write (write the seventh entry, at the indirect address offset 0x06)
Write to Reg. IADR5 (VLAN table bits [19:16])
Write to Reg. IADR4 (VLAN table bits [15:0])
Write to Reg. IACR with 0x1406 (set indirect address and trigger a read VLAN table operation)
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5.0
OPERATIONAL CHARACTERISTICS
5.1
Absolute Maximum Ratings*
Supply Voltage
(VDDATX, VDDARX, VDDIO).......................................................................................................................... –0.5V to +4.0V
Input Voltage (all inputs)............................................................................................................................ –0.5V to +5.0V
Output Voltage (all outputs)....................................................................................................................... –0.5V to +4.0V
Storage Temperature (TS) ......................................................................................................................–55°C to +150°C
Lead Temperature (Soldering, 10 sec)..................................................................................................................+270°C
*Exceeding the absolute maximum rating may damage the device. Stresses greater than those listed in the table above
may cause permanent damage to the device. Operation of the device at these or any other conditions above those specified in the operating sections of this specification is not implied. Maximum conditions for extended periods may affect
reliability. Unused inputs must always be tied to an appropriate logic voltage level.
5.2
Operating Ratings**
Supply Voltage
(VDDATX, VDDARX, VDDIO).......................................................................................................................... +3.1V to +3.5V
Ambient Operating Temperature for Commercial Options (TA)....................................................................0°C to +70°C
Maximum Junction Temperature (TJ) ....................................................................................................................+125°C
Thermal Resistance (Note 5-1) (ΘJA) ........................................................................................................... +42.91°C/W
Thermal Resistance (Note 5-1) (ΘJC) ............................................................................................................. +19.6°C/W
**The device is not guaranteed to function outside its operating ratings. Unused inputs must always be tied to an appropriate logic voltage level (Ground to VDD).
Note 5-1
Note:
No heat spreader (HS) in this package. The ΘJC/ΘJA is under air velocity 0 m/s.
Do not drive input signals without power supplied to the device.
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6.0
ELECTRICAL CHARACTERISTICS
TA = 25°C. Specification is for packaged product only. Single port’s transformer consumes an additional 45 mA @ 3.3V
for 100BASE-TX and 70 mA @ 3.3V for 10BASE-T.
TABLE 6-1:
ELECTRICAL CHARACTERISTICS
Parameters
Symbol
Min.
Typ.
Max.
Units
Condition
Supply Current for 100BASE-TX Operation (Single Port @ 100% Utilization)
100BASE-TX
(analog core + PLL +
digital core + transceiver +
digital I/O)
IDDXIO
—
122
—
mA
VDDATX, VDDARX, VDDIO = 3.3V,
Chip only (no transformer)
Supply Current for 10BASE-T Operation (Single Port @ 100% Utilization)
10BASE-T
(analog core + PLL +
digital core + transceiver +
digital I/O)
—
mA
VDDATX, VDDARX, VDDIO = 3.3V,
Chip only (no transformer)
—
—
V
—
—
0.8
V
—
–10
—
10
μA
VIN = GND ~ VDDIO
VOH
2.4
—
—
V
IOH = –8 mA
VOL
—
—
0.4
V
IOL = 8 mA
|IOZ|
—
—
10
μA
—
IDDXIO
—
90
Input High Voltage
VIH
2.0
Input Low Voltage
VIL
—
Input Current
IIN
Output High Voltage
Output Low Voltage
Output Tri-State Leakage
CMOS Inputs
CMOS Outputs
100BASE-TX Transmit (measured differentially after 1:1 transformer)
Peak Differential Output
Voltage
VO
±0.95
—
±1.05
V
100Ω termination on the differential
output.
Output Voltage Imbalance
VIMB
—
—
2
%
100Ω termination on the differential
output.
Rise/Fall Time
tr/tf
3
—
5
ns
—
Rise/Fall Time Imbalance
—
0
—
0.5
ns
—
Duty Cycle Distortion
—
—
—
±0.25
ns
—
Overshoot
—
—
—
5
%
—
Reference Voltage of ISET
VSET
—
0.5
—
V
—
Output Jitter
—
—
0.7
1.4
ns
Peak-to-peak
10BASE-T Transmit (measured differentially after 1:1 transformer)
Peak Differential Output
Voltage
VO
—
2.4
—
V
100Ω termination on the differential
output.
Output Jitter
—
—
1.8
3.5
ns
Peak-to-peak
VSQ
—
400
—
mV
5 MHz square wave
10BASE-T Receive
Squelch Threshold
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7.0
TIMING SPECIFICATIONS
7.1
Asynchronous Timing without using Address Strobe (ADSN = 0)
FIGURE 7-1:
ASYNCHRONOUS CYCLE – ADSN = 0
t2
valid
Addr, AEN, BExN
ADSN
t3
t4
Read Data
valid
t1
t5
RDN, WRN
t6
Write Data
valid
t7
ARDY
(Read Cycle)
t9
ARDY
(Write Cycle)
TABLE 7-1:
Parameter
t1
t3
t10
ASYNCHRONOUS CYCLE (ADSN = 0) TIMING PARAMETERS
Symbol
t2
t8
Min.
Typ.
Max.
Units
A1-A15, AEN, BExN[3:0] valid to RDN, WRN active
0
—
—
ns
A1-A15, AEN, BExN[3:0] hold after RDN inactive (assume ADSN tied
Low)
0
—
—
A1-A15, AEN, BExN[3:0] hold after WRN inactive (assume ADSN
tied Low)
1
—
—
Read data valid to ARDY rising
—
—
0.8
ns
ns
t4
Read data to hold RDN inactive
4
—
—
ns
t5
Write data setup to WRN inactive
4
—
—
ns
t6
Write data hold after WRN inactive
2
—
—
ns
t7
Read active to ARDY Low
—
—
8
ns
ns
t8
t9
t10
Write inactive to ARDY Low
—
—
8
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 40 ns to read QMU data
register in turbo mode) (Note 7-2)
0
40
—
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 80 ns to read QMU data
register in normal mode)
0
80
—
ARDY low (wait time) in write cycle (Note 7-1)
(It is 0 ns to write bank select register)
(It is 36 ns to write QMU data register)
0
50
—
ns
ns
Note 7-1
When CPU finished current Read or Write operation, it can do next Read or Write operation even
the ARDY is low. During Read or Write operation if the ADRY is low, the CPU has to keep the RDN/
WRN low until the ARDY returns to high.
Note 7-2
In order to speed up the ARDY low time to 40 ns, user has to use the turbo software driver which
is only supported in the A6 device. Please refer to the “KSZ88xx Programmer's Guide” for detail.
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7.2
Asynchronous Timing using Address Strobe (ADSN)
FIGURE 7-2:
ASYNCHRONOUS CYCLE – USING ADSN
t8
valid
Addr, AEN, BExN
t6
ADSN
Read Data
valid
t1
t4
t3
RDN, WRN
t5
Write Data
valid
t7
ARDY
(Read Cycle)
t2
t10
ARDY
(Write Cycle)
TABLE 7-2:
t9
t11
ASYNCHRONOUS CYCLE USING ADSN TIMING PARAMETERS
Symbol
Parameter
Min.
Typ.
Max.
Units
t1
A1-A15, AEN, BExN[3:0] valid to RDN, WRN active
0
—
—
ns
t2
Read data valid to ARDY rising
—
—
0.8
ns
t3
Read data hold to RDN inactive
4
—
—
ns
t4
Write data setup to WRN inactive
4
—
—
ns
t5
Write data hold after WRN inactive
2
—
—
ns
t6
A1-A15, AEN, nBE[3:0] setup to ADSN rising
4
—
—
ns
t7
Read active to ARDY Low
—
—
8
ns
t8
A1-A15, AEN, BExN[3:0] hold after ADSN rising
2
—
—
ns
t9
Write inactive to ARDY Low
—
—
8
ns
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 40 ns to read QMU data
register in turbo mode) (Note 7-2)
0
40
—
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 80 ns to read QMU data
register in normal mode)
0
80
—
ARDY low (wait time) in write cycle (Note 7-1)
(It is 0 ns to write bank select register)
(It is 36 ns to write QMU data register)
0
50
—
t10
t11
ns
ns
Note 7-1
When CPU finished current Read or Write operation, it can do next Read or Write operation even
the ARDY is low. During Read or Write operation if the ADRY is low, the CPU has to keep the RDN/
WRN low until the ARDY returns to high.
Note 7-2
In order to speed up the ARDY low time to 40 ns, user has to use the turbo software driver which
is only supported in the A6 device. Please refer to the “KSZ88xx Programmer's Guide” for detail.
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7.3
Asynchronous Timing using DATACSN (KSZ8842-32MQL/MVL Only)
FIGURE 7-3:
ASYNCHRONOUS CYCLE – USING DATACSN
t2
DATACSN
Read Data
valid
t1
t5
t4
RDN, WRN
t6
valid
Write Data
t7
ARDY
(Read Cycle)
t3
t9
t8
ARDY
(Write Cycle)
TABLE 7-3:
t10
ASYNCHRONOUS CYCLE USING DATACSN TIMING PARAMETERS
Symbol
Parameter
t1
DATACSN setup to RDN, WRN active
Min.
Typ.
Max.
Units
2
—
—
ns
t2
DATACSN hold after RDN, WRN inactive (assume ADSN tied Low)
0
—
—
ns
t3
Read data hold to ARDY rising
—
—
0.8
ns
t4
Read data to RDN hold
4
—
—
ns
t5
Write data setup to WRN inactive
4
—
—
ns
t6
Write data hold after WRN inactive
2
—
—
ns
t7
Read active to ARDY Low
—
—
8
ns
ns
t8
t9
t10
Write inactive to ARDY Low
—
—
8
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 40 ns to read QMU data
register in turbo mode) (Note 7-2)
0
40
—
ARDY low (wait time) in read cycle (Note 7-1)
(It is 0 ns to read bank select register and 80 ns to read QMU data
register in normal mode)
0
80
—
ARDY low (wait time) in write cycle (Note 7-1)
(It is 0 ns to write bank select register)
(It is 85 ns to write QMU data register)
0
50
—
ns
ns
Note 7-1
When CPU finished current Read or Write operation, it can do next Read or Write operation even
the ARDY is low. During Read or Write operation if the ADRY is low, the CPU has to keep the RDN/
WRN low until the ARDY returns to high.
Note 7-2
In order to speed up the ARDY low time to 40 ns, user has to use the turbo software driver which
is only supported in the A6 device. Please refer to the “KSZ88xx Programmer's Guide” for detail.
2020 Microchip Technology Inc.
DS00003459A-page 113
KSZ8842-16M/-32M
7.4
Address Latching Timing for All Modes
FIGURE 7-4:
ADDRESS LATCHING CYCLE FOR ALL MODES
t1
ADSN
t2
Address, AEN, BExN
t3
LDEVN
TABLE 7-4:
Symbol
ADDRESS LATCHING TIMING PARAMETERS
Parameter
Min.
Typ.
Max.
Units
t1
A1-A15, AEN, BExN[3:0] setup to ADSN
4
—
—
ns
t2
A1-A15, AEN, BExN[3:0] hold after ADSN rising
2
—
—
ns
t3
A4-A15, AEN to LDEVN delay
—
—
5
ns
DS00003459A-page 114
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
7.5
Synchronous Timing in Burst Write (VLBUSN = 1)
FIGURE 7-5:
TABLE 7-5:
SYNCHRONOUS BURST WRITE CYCLES – VLBUSN = 1
SYNCHRONOUS BURST WRITE TIMING PARAMETERS
Symbol
Parameter
Min.
Max.
Units
t1
t2
SWR setup to BCLK falling
4
—
ns
DATDCSN setup to BCLK rising
4
—
ns
t3
CYCLEN setup to BCLK rising
4
—
ns
t4
Write data setup to BCLK rising
6
—
ns
t5
Write data hold to BCLK rising
2
—
ns
t6
RDYRTNN setup to BCLK falling
5
—
ns
t7
RDYRTNN hold to BCLK falling
3
—
ns
t8
SRDYN setup to BCLK rising
4
—
ns
t9
SRDYN hold to BCLK rising
3
—
ns
t10
DATACSN hold to BCLK rising
2
—
ns
t11
SWR hold to BCLK falling
2
—
ns
t12
CYCLEN hold to BCLK rising
2
—
ns
2020 Microchip Technology Inc.
DS00003459A-page 115
KSZ8842-16M/-32M
7.6
Synchronous Timing in Burst Read (VLBUSN = 1)
FIGURE 7-6:
SYNCHRONOUS BURST READ CYCLES – VLBUSN = 1
BCLK
t10
t2
DATACSN
t11
t1
SWR
t12
t3
CYCLEN
t5
t4
data0
Read Data
data1
data2
data3
t7
t6
RDYRTNN
t8
t9
SRDYN
TABLE 7-6:
SYNCHRONOUS BURST READ TIMING PARAMETERS
Symbol
Parameter
Min.
Max.
Units
t1
t2
SWR setup to BCLK falling
4
—
ns
DATDCSN setup to BCLK rising
4
—
ns
t3
CYCLEN setup to BCLK rising
4
—
ns
t4
Read data setup to BCLK rising
6
—
ns
t5
Read data hold to BCLK rising
2
—
ns
t6
RDYRTNN setup to BCLK falling
5
—
ns
t7
RDYRTNN hold to BCLK falling
3
—
ns
t8
SRDYN setup to BCLK rising
4
—
ns
t9
SRDYN hold to BCLK rising
3
—
ns
t10
DATACSN hold to BCLK rising
2
—
ns
t11
SWR hold to BCLK falling
2
—
ns
t12
CYCLEN hold to BCLK rising
2
—
ns
DS00003459A-page 116
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
7.7
Synchronous Write Timing (VLBUSN = 0)
FIGURE 7-7:
SYNCHRONOUS WRITE CYCLE – VLBUSN = 0
BCLK
t2
Address, AEN, BExN
valid
t1
ADSN
t5
t6
SWR
t4
t3
CYCLEN
t7
Write Data
t8
valid
t9
t10
SRDYN
t11
t12
RDYRTNN
TABLE 7-7:
SYNCHRONOUS WRITE (VLBUSN = 0) TIMING PARAMETERS
Symbol Parameter
t1
A1-A15, AEN, BExN[3:0] setup to ADSN rising
Min.
Typ.
Max.
Units
4
—
—
ns
t2
A1-A15, AEN, BExN[3:0] hold after ADSN rising
2
—
—
ns
t3
CYCLEN setup to BCLK rising
4
—
—
ns
t4
CYCLEN hold after BCLK rising (non-burst mode)
2
—
—
ns
t5
SWR setup to BCLK
4
—
—
ns
t6
SWR hold after BCLK rising with SRDYN active
0
—
—
ns
t7
Write data setup to BCLK rising
5
—
—
ns
t8
Write data hold from BCLK rising
1
—
—
ns
t9
SRDYN setup to BCLK
8
—
—
ns
t10
SRDYN hold to BCLK
1
—
—
ns
t11
RDYRTNN setup to BCLK
4
—
—
ns
t12
RDYRTNN hold to BCLK
1
—
—
ns
2020 Microchip Technology Inc.
DS00003459A-page 117
KSZ8842-16M/-32M
7.8
Synchronous Read Timing (VLBUSN = 0)
FIGURE 7-8:
SYNCHRONOUS READ CYCLE – VLBUSN = 0
BCLK
t2
Address, AEN, BExN
valid
t1
ADSN
t5
SWR
t4
t3
CYCLEN
t7
Read Data
t6
valid
t8
t9
SRDYN
t10
t11
RDYRTNN
TABLE 7-8:
SYNCHRONOUS READ (VLBUSN = 0) TIMING PARAMETERS
Symbol Parameter
t1
A1-A15, AEN, BExN[3:0] setup to ADSN rising
Min.
Typ.
Max.
Units
4
—
—
ns
t2
A1-A15, AEN, BExN[3:0] hold after ADSN rising
2
—
—
ns
t3
CYCLEN setup to BCLK rising
4
—
—
ns
t4
CYCLEN hold after BCLK rising (non-burst mode)
2
—
—
ns
t5
SWR setup to BCLK
4
—
—
ns
t6
Read data hold from BCLK rising
1
—
—
ns
t7
Read data setup to BCLK
8
—
—
ns
t8
SRDYN setup to BCLK
8
—
—
ns
t9
SRDYN hold to BCLK
1
—
—
ns
t10
RDYRTNN setup to BCLK rising
4
—
—
ns
t11
RDYRTNN hold after BCLK rising
1
—
—
ns
DS00003459A-page 118
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
7.9
EEPROM Timing
FIGURE 7-9:
EEPROM READ CYCLE TIMING DIAGRAM
EECS
*1
EESK
1
tcyc
EEDO
11
0
An
ts
A0
th
High-Z
EEDI
D15
D14
D1
D13
D0
*1 Start bit
TABLE 7-9:
EEPROM TIMING PARAMETERS
Symbol Parameter
Min.
Typ.
Max.
Units
—
μs
tcyc
Clock cycle
—
4 (OBCR[1:0]=11 on-chip
bus speed @ 25 MHz)
or
0.8 (OBCR[1:0]=00
on-chip bus speed @
125 MHz)
ts
Setup time
20
—
—
ns
th
Hold time
20
—
—
ns
2020 Microchip Technology Inc.
DS00003459A-page 119
KSZ8842-16M/-32M
7.10
Auto-Negotiation Timing
FIGURE 7-10:
TABLE 7-10:
AUTO-NEGOTIATION TIMING
AUTO-NEGOTIATION TIMING PARAMETERS
Symbol Parameter
Min.
Typ.
Max.
Units
16
24
ms
tBTB
FLP burst to FLP burst
8
tFLPW
FLP burst width
—
2
—
ms
tPW
Clock/Data pulse width
—
100
—
ns
tCTD
Clock pulse to data pulse
55.5
64
69.5
μs
tCTC
Clock pulse to clock pulse
111
128
139
μs
—
Number of Clock/Data pulses per burst
17
—
33
—
DS00003459A-page 120
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
7.11
Reset Timing
As long as the stable supply voltages to reset High timing (minimum of 10 ms) are met, there is no power-sequencing
requirement for the KSZ8842M supply voltages (3.3V).
The reset timing requirement is summarized in Figure 7-11 and Table 7-11.
FIGURE 7-11:
RESET TIMING
Supply
Voltage
tsr
RST_N
TABLE 7-11:
RESET TIMING PARAMETERS
Parameter
Description
tSR
Stable supply voltages to reset high
2020 Microchip Technology Inc.
Min.
Typ.
Max.
Units
10
—
—
ms
DS00003459A-page 121
KSZ8842-16M/-32M
8.0
SELECTION OF ISOLATION TRANSFORMERS
A 1:1 isolation transformer is required at the line interface. An isolation transformer with integrated common-mode choke
is recommended for exceeding FCC requirements.
Table 8-1 lists recommended transformer characteristics.
TABLE 8-1:
TRANSFORMER SELECTION CRITERIA
Parameter
Value
Test Conditions
Turns Ratio
1 CT : 1 CT
—
Open-Circuit Inductance (min.)
350 μH
100 mV, 100 kHz, 8 mA
Leakage Inductance (max.)
0.4 μH
1 MHz (min.)
Interwinding Capacitance (max.)
12 pF
—
D.C. Resistance (max.)
0.9Ω
—
Insertion Loss (max.)
1.0 dB
0 MHz to 65 MHz
HIPOT (min.)
1500 VRMS
—
TABLE 8-2:
QUALIFIED SINGLE-PORT MAGNETICS
Manufacturer
Part Number
Bel Fuse
S558-5999-U7
Yes
Delta
LF8505
Yes
LanKom
LF-H41S
Yes
Pulse
H1102
Yes
Pulse (Low Cost)
H1260
Yes
Transpower
HB726
Yes
TDK (Mag Jack)
TLA-6T718
Yes
TABLE 8-3:
Auto MDI-X
TYPICAL REFERENCE CRYSTAL CHARACTERISTICS
Characteristic
DS00003459A-page 122
Value
Frequency
25 MHz
Frequency Tolerance (max.)
±50 ppm
Load Capacitance (max.)
20 pF
Series Resistance
25Ω
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
9.0
PACKAGE OUTLINE
9.1
Package Marking Information
128-Lead PQFP*
XXXXXX
XXXXXXX-XX
XXX
YYWWXXX
XXXXXYYWWNNN
YYWWNNN
128-Lead LQFP*
e3
MICREL
KSZ8842-16
MQL
2013A7B
G00002013805
2013805
Example
XXXXXX
XXXXXXX-XX
XXX
YYWWXXX
XXXXXYYWWNNN
YYWWNNN
MICREL
KSZ8842-32
MVL
1951A7C
G00001951469
1951469
100-Lead LFBGA*
100-Lead LFBGA*
XXXXXX
XXXXXXX-XX
XXX
YYWWXXX
XXXXXYYWWNNN
YYWWNNN
MICREL
KSZ8842-16
MBL
2044A7L
G00002044231
2044231
Legend: XX...X
Y
YY
WW
NNN
*
Example
Product code or customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC® designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
●, ▲, ▼ Pin one index is identified by a dot, delta up, or delta down (triangle
mark).
Note:
In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line, thus limiting the number of available
characters for customer-specific information. Package may or may not include
the corporate logo.
Underbar (_) and/or Overbar (‾) symbol may not be to scale.
2020 Microchip Technology Inc.
DS00003459A-page 123
KSZ8842-16M/-32M
FIGURE 9-1:
Note:
128-LEAD PQFP 14 MM X 20 MM PACKAGE OUTLINE AND RECOMMENDED
LAND PATTERN
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging.
DS00003459A-page 124
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
FIGURE 9-2:
Note:
128-LEAD 14 MM X 14 MM PACKAGE OUTLINE AND RECOMMENDED LAND
PATTERN
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging.
2020 Microchip Technology Inc.
DS00003459A-page 125
KSZ8842-16M/-32M
FIGURE 9-3:
Note:
100-LEAD LFBGA 10 MM X 10 MM PACKAGE OUTLINE AND RECOMMENDED
LAND PATTERN
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging.
DS00003459A-page 126
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
APPENDIX A:
TABLE A-1:
DATA SHEET REVISION HISTORY
REVISION HISTORY
Revision
DS00003459A (04-20-20)
2020 Microchip Technology Inc.
Section/Figure/Entry
—
Correction
Converted Micrel data sheet KSZ8842-16M/-32M to
Microchip DS00003459A. Minor text changes
throughout.
DS00003459A-page 127
KSZ8842-16M/-32M
THE MICROCHIP WEB SITE
Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make
files and information easily available to customers. Accessible by using your favorite Internet browser, the web site contains the following information:
• Product Support – Data sheets and errata, application notes and sample programs, design resources, user’s
guides and hardware support documents, latest software releases and archived software
• General Technical Support – Frequently Asked Questions (FAQ), technical support requests, online discussion
groups, Microchip consultant program member listing
• Business of Microchip – Product selector and ordering guides, latest Microchip press releases, listing of seminars and events, listings of Microchip sales offices, distributors and factory representatives
CUSTOMER CHANGE NOTIFICATION SERVICE
Microchip’s customer notification service helps keep customers current on Microchip products. Subscribers will receive
e-mail notification whenever there are changes, updates, revisions or errata related to a specified product family or
development tool of interest.
To register, access the Microchip web site at www.microchip.com. Under “Support”, click on “Customer Change Notification” and follow the registration instructions.
CUSTOMER SUPPORT
Users of Microchip products can receive assistance through several channels:
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Customers should contact their distributor, representative or field application engineer (FAE) for support. Local sales
offices are also available to help customers. A listing of sales offices and locations is included in the back of this document.
Technical support is available through the web site at: http://microchip.com/support
DS00003459A-page 128
2020 Microchip Technology Inc.
KSZ8842-16M/-32M
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
Examples:
Device
-XX
X
X
X
[X]
[-XX]
Part
Number
Bus
Design
Interface
Package
Supply
Voltage
Temperature
Media
Type
Device:
KSZ8842: Two-Port Ethernet Switch with Non-PCI Interface
Bus Design:
-16 = 8-bit or 16-bit
-32 = 32-bit
Interface:
M = Non-PCI Interface
Package:
Q = 128-lead PQFP
V = 128-lead LQFP
B = 100-lead LFBGA
a) KSZ8842-16MQL:
8-Bit or 16-Bit Bus Design, Non-PCI
Interface, 128-Lead PQFP, Single
3.3V Power Supply with Internal 1.8V
LDO, Commercial Temperature
Range, 66/Tray
b) KSZ8842-16MBL-TR:
Supply Voltage:
L = Single 3.3V Power Supply Supported with Internal 1.8V
LDO
Temperature:
= 0C to +70C (Commercial)
I = –40C to +85C (Industrial)
Media Type:
= 66/Tray (PQFP Only)
= 90/Tray (LQFP Only)
= 240/Tray (LFBGA Only)
TR = 1,000/Reel (LQFP & LFBGA Only)
8-Bit or 16-Bit Bus Design, Non-PCI
Interface, 100-Lead LFBGA, Single
3.3V Power Supply with Internal 1.8V
LDO, Commercial Temperature
Range, 1,000/Reel
c) KSZ8842-32MVLI:
32-Bit Bus Design, Non-PCI
Interface, 128-Lead LQFP, Single
3.3V Power Supply with Internal 1.8V
LDO, Industrial Temperature
Range, 90/Tray
d) KSZ8842-32MVL-TR:
32-Bit Bus Design, Non-PCI
Interface, 128-Lead LQFP, Single
3.3V Power Supply with Internal 1.8V
LDO, Commercial Temperature
Range, 1,000/Reel
e) KSZ8842-16MBLI:
8-Bit or 16-Bit Bus Design, Non-PCI
Interface, 100-Lead LFBGA, Single
3.3V Power Supply with Internal 1.8V
LDO, Industrial Temperature
Range, 240/Tray
f) KSZ8842-32MQL:
32-Bit Bus Design, Non-PCI
Interface, 128-Lead PQFP, Single
3.3V Power Supply with Internal 1.8V
LDO, Industrial Temperature
Range, 66/Tray
g) KSZ8842-16MVL:
16-Bit Bus Design, Non-PCI
Interface, 128-Lead LQFP, Single
3.3V Power Supply with Internal 1.8V
LDO, Commercial Temperature
Range, 90/Tray
Note 1:
2020 Microchip Technology Inc.
Tape and Reel identifier only appears in the
catalog part number description. This identifier
is used for ordering purposes and is not
printed on the device package. Check with
your Microchip Sales Office for package
availability with the Tape and Reel option.
DS00003459A-page 129
KSZ8842-16M/-32M
NOTES:
DS00003459A-page 130
2020 Microchip Technology Inc.
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
mean that we are guaranteeing the product as “unbreakable.”
Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.
Information contained in this publication regarding device applications and the like is provided only for your convenience and may be
superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO
REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR
OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE,
MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of
Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and
hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights unless otherwise stated.
Trademarks
The Microchip name and logo, the Microchip logo, Adaptec, AnyRate, AVR, AVR logo, AVR Freaks, BesTime, BitCloud, chipKIT, chipKIT logo,
CryptoMemory, CryptoRF, dsPIC, FlashFlex, flexPWR, HELDO, IGLOO, JukeBlox, KeeLoq, Kleer, LANCheck, LinkMD, maXStylus, maXTouch,
MediaLB, megaAVR, Microsemi, Microsemi logo, MOST, MOST logo, MPLAB, OptoLyzer, PackeTime, PIC, picoPower, PICSTART, PIC32 logo,
PolarFire, Prochip Designer, QTouch, SAM-BA, SenGenuity, SpyNIC, SST, SST Logo, SuperFlash, Symmetricom, SyncServer, Tachyon,
TempTrackr, TimeSource, tinyAVR, UNI/O, Vectron, and XMEGA are registered trademarks of Microchip Technology Incorporated in the U.S.A.
and other countries.
APT, ClockWorks, The Embedded Control Solutions Company, EtherSynch, FlashTec, Hyper Speed Control, HyperLight Load, IntelliMOS, Libero,
motorBench, mTouch, Powermite 3, Precision Edge, ProASIC, ProASIC Plus, ProASIC Plus logo, Quiet-Wire, SmartFusion, SyncWorld, Temux,
TimeCesium, TimeHub, TimePictra, TimeProvider, Vite, WinPath, and ZL are registered trademarks of Microchip Technology Incorporated in the
U.S.A.
Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BlueSky, BodyCom, CodeGuard,
CryptoAuthentication, CryptoAutomotive, CryptoCompanion, CryptoController, dsPICDEM, dsPICDEM.net, Dynamic Average Matching, DAM,
ECAN, EtherGREEN, In-Circuit Serial Programming, ICSP, INICnet, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, memBrain,
Mindi, MiWi, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, Omniscient Code Generation, PICDEM, PICDEM.net,
PICkit, PICtail, PowerSmart, PureSilicon, QMatrix, REAL ICE, Ripple Blocker, SAM-ICE, Serial Quad I/O, SMART-I.S., SQI, SuperSwitcher,
SuperSwitcher II, Total Endurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other countries.
SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.
The Adaptec logo, Frequency on Demand, Silicon Storage Technology, and Symmcom are registered trademarks of Microchip Technology Inc. in
other countries.
GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary of Microchip Technology Inc., in other
countries.
All other trademarks mentioned herein are property of their respective companies.
© 2020, Microchip Technology Incorporated, All Rights Reserved.
ISBN: 978-1-5224-5951-4
For information regarding Microchip’s Quality Management Systems,
please visit www.microchip.com/quality.
2020 Microchip Technology Inc.
DS00003459A-page 131
Worldwide Sales and Service
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Tel: 86-21-3326-8000
Singapore
Tel: 65-6334-8870
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
China - Shenyang
Tel: 86-24-2334-2829
Taiwan - Hsin Chu
Tel: 886-3-577-8366
Germany - Rosenheim
Tel: 49-8031-354-560
China - Shenzhen
Tel: 86-755-8864-2200
Taiwan - Kaohsiung
Tel: 886-7-213-7830
Israel - Ra’anana
Tel: 972-9-744-7705
China - Suzhou
Tel: 86-186-6233-1526
Taiwan - Taipei
Tel: 886-2-2508-8600
China - Wuhan
Tel: 86-27-5980-5300
Thailand - Bangkok
Tel: 66-2-694-1351
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
China - Xian
Tel: 86-29-8833-7252
Vietnam - Ho Chi Minh
Tel: 84-28-5448-2100
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Austin, TX
Tel: 512-257-3370
Boston
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Tel: 774-760-0087
Fax: 774-760-0088
Chicago
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Tel: 630-285-0071
Fax: 630-285-0075
Dallas
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Tel: 972-818-7423
Fax: 972-818-2924
Detroit
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Tel: 248-848-4000
Houston, TX
Tel: 281-894-5983
Indianapolis
Noblesville, IN
Tel: 317-773-8323
Fax: 317-773-5453
Tel: 317-536-2380
Los Angeles
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Tel: 949-462-9523
Fax: 949-462-9608
Tel: 951-273-7800
Raleigh, NC
Tel: 919-844-7510
New York, NY
Tel: 631-435-6000
San Jose, CA
Tel: 408-735-9110
Tel: 408-436-4270
Canada - Toronto
Tel: 905-695-1980
Fax: 905-695-2078
DS00003459A-page 132
China - Xiamen
Tel: 86-592-2388138
China - Zhuhai
Tel: 86-756-3210040
Germany - Garching
Tel: 49-8931-9700
Germany - Haan
Tel: 49-2129-3766400
Germany - Heilbronn
Tel: 49-7131-72400
Germany - Karlsruhe
Tel: 49-721-625370
Italy - Padova
Tel: 39-049-7625286
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Norway - Trondheim
Tel: 47-7288-4388
Poland - Warsaw
Tel: 48-22-3325737
Romania - Bucharest
Tel: 40-21-407-87-50
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
Sweden - Gothenberg
Tel: 46-31-704-60-40
Sweden - Stockholm
Tel: 46-8-5090-4654
UK - Wokingham
Tel: 44-118-921-5800
Fax: 44-118-921-5820
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02/28/20
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