THDB-HDMI
Terasic HDMI Video Daughter Board
User Manual
1
CONTENTS
Chapter 1 Introduction ...................................................................................... 2
1.1 About the KIT .......................................................................................................................................... 2
1.2 Assemble the HDMI Board ...................................................................................................................... 3
1.3 Getting Help ............................................................................................................................................. 3
Chapter 2 HDMI Board ....................................................................................... 4
2.1 Features .................................................................................................................................................... 4
2.2 Layout and Componets ............................................................................................................................ 7
2.3 Block Diagram of HDMI Signal Transmission........................................................................................ 8
2.4 Block Diagram of HDMI Signal Receiving ........................................................................................... 10
2.5 Generate Pin Assignments ..................................................................................................................... 11
2.6 Pin Definition of HSTC Connector ........................................................................................................ 13
Chapter 3 Demonstration ................................................................................ 21
3.1 Introduction ............................................................................................................................................ 21
3.2 System Requirements............................................................................................................................. 21
3.3 Setup the Demonstration ........................................................................................................................ 22
3.4 Operation................................................................................................................................................ 23
Chapter 4 Case Study ....................................................................................... 27
4.1 Overview ................................................................................................................................................ 27
4.2 System Function Block .......................................................................................................................... 27
4.3 NIOS Program ....................................................................................................................................... 31
Chapter 5 Appendix ......................................................................................... 35
5.1 Revision History .................................................................................................................................... 35
5.2 Always Visit THDB-HDMI Webpage for Update.................................................................................. 35
1
Chapter 1
Introduction
THDB-HDMI is a HDMI transmitter/receiver daughter board with HSTC (High Speed Terasic
Connector) interface. Host boards, supporting HSTC-compliant connectors, can control the HDMI
daughter board through the HSTC interface.
This THDB-HDMI kit contains complete reference designs with source code written in Verilog and
C, for HDMI signal transmitting and receiving. Based on reference designs, users can easily and
quickly develop their applications.
1.1 About the KIT
This section describes the package content.
The THDB-HDMI package, as shown in Figure 1-1, contains:
THDB-HDMI board x 1
System CD-ROM x 1
The CD contains technical documents of the HDMI receiver and transmitter, and one reference
design for HDMI transmitting and receiving with source code.
Figure 1-1 THDB-HDMI Package
2
1.2 Assemble the HDMI Board
This section describes how to connect the HDMI daughter board to a main board, and use DE3 as
an example.
The HDMI board connects to main boards through the HSTC interface. For DE3, the HDMI
daughter board can be connected to any one of four HSTC connectors on DE3.
Figure 1-2 shows a HDMI daughter board connected to the HSTC connector of DE3. Due to high
speed data rate in between, users are strongly recommended to screw the two boards together.
Note. Do not attempt to connect/remove the HDMI daughter board to/from the main board when the
power is on, or the hardware could be damaged.
Figure 1-2 Connect HDMI daughter board to DE3 board
1.3 Getting Help
Here are some places to get help if you encounter any problem:
Email to support@terasic.com
Taiwan: +886-3-570-0880
China : +86-27-8774-5390
3
Chapter 2
HDMI Board
This chapter will illustrate technical details of HDMI board. Users may modify the reference
designs for various purposes accordingly.
2.1 Features
This section describes the major features of the HDMI board.
Board Features:
One HSTC interface for connection purpose
One HDMI transmitter with single transmitting port
One HDMI receiver with dual receiving ports
Two 2K EEPROM for storing EDID of two receiver ports separately
Powered from 3.3V pins of HSTC connector
HDMI Transmitter Features:
1.
HDMI 1.4 transmitter
2.
Compliant with HDMI 1.3, HDMI1.4a 3D,HDCP 1.4 and DVI 1.1 specifications
3.
Supporting link speeds of up to 2.25 Gbps (link clock rate of 225MHZ)
4.
Supporting diverse 3D formats which are compliant with HDMI 1.4a 3D specification.
o Supporting 3D video up to 1080P@23.98/24/30Hz,1080i@50/59.94/60/Hz
o Supporting formats: framing packing, side-by-side(half),top-and-bottom
5.
Various video input interface supporting digital video standards such as:
o 24/30/36-bit RGB/YCbCr 4:4:4
o 16/20/24-bit YCbCr 4:2:2
o 8/10/12-bit YCbCr 4:2:2 (CCIR-656)
6.
Bi-direction Color Space Conversion (CSC) between RGB and YCbCr color space with
programmable coefficients
4
7.
Up/down sampling between YCbCr 4:4:4 and YCbCr 4:2:2
8.
Either for conversion from 12-bit/10-bit to component to 8-bit
9.
Support Gammat Metadata packet
10. Digital audio input interface supporting:
o Up to four I2S interface supporting 8-channel audio, with sample rates of 32~192
kHz and sample sizes of 16~24 bits
o S/PDIF interface supporting PCM, Dolby Digital, DTS digital audio at up to 192kHz
frame rate
o Support for high-bit-rate (HBR) audio such as DTS-HD and Dolby TrueHD through
the four I2S interface or the S/PDIF interface, with frame rates as high as 768kHz
o Support for 8-channel DSD audio through dedicated inputs
o Compatible with IEC 60958 and IEC 61937
o Audio down-sampling of 2X and 4X
11. Software programmable, auto-calibrated TMDS source terminations provide for optimal
source signal quality
12. Software programmable HDMI output current level
13. MCLK input is optional for audio operation. Users could opt to implement audio input
interface with or without MCLK
14. Integrated pre-programmed HDCP keys
15. Purely hardware HDCP engine increasing the robustness and security of HDCP operation
16. Monitor detection through Hot Plug Detection and Receiver Termination Detection
17. Embedded full-function pattern generator
18. Intelligent, programmable power management
Table 2-1 lists supported input video format:
Table 2-1 Input video formats supported by the HDMI board
Input Pixel Clock Frequency(MHz)
Color
Video
Bus
Hsync/
space
Format
Width
Vsync
24
RGB
4:4:4
30/36
12/15/18
24
4:4:4
YCbCr
30/36
12/15/18
4:2:2
16/20/24
480i
480p
XGA
720p
1080i
SXGA
1080p
UXGA
13.5
27
65
74.25
74.25
108
148.5
162
13.5
27
65
74.25
74.25
108
148.5
13.5
27
65
74.25
74.25
13.5
27
65
74.25
74.25
108
148.5
13.5
27
65
74.25
74.25
108
148.5
Separate
13.5
27
65
74.25
74.25
Separate
13.5
27
74.25
74.25
148.5
Embedded
13.5
27
74.25
74.25
148.5
Separate
Separate
Separate
5
162
12/15/18
Separate
27
54
148.5
148.5
Embedded
27
54
148.5
148.5
HDMI Receiver Features:
1.
Dual-Port HDMI 1.4 receiver
2.
Compliant with HDMI 1.3, HDMI1.4a 3D,HDCP 1.4 and DVI 1.1 specifications
3.
Supporting link speeds of up to 2.25 Gbps (link clock rate of 225MHZ)
4.
Supporting diverse 3D formats which are compliant with HDMI 1.4a 3D specification.
o Supporting 3D video up to 1080P@23.98/24/30Hz,1080i@50/59.94/60/Hz
o Supporting formats: framing packing, side-by-side(half),top-and-bottom
5.
Various video input interface supporting digital video standards such as:
o 24/30/36-bit RGB/YCbCr 4:4:4
o 16/20/24-bit YCbCr 4:2:2
o 8/10/12-bit YCbCr 4:2:2 (ITU BT-656)
o 12/15/18-bit double data rate interface (data bus width halved, clocked with both
rising and falling edges) for RGB/YCbCr 4:4:4
o 24/30/36-bit double data rate interface (full bus width, pixel clock rate halved,
clocked with both rising and falling edges)
o Input channel swap
o MSB/LSB swap
6.
Bi-direction Color Space Conversion (CSC) between RGB and YCbCr color space with
programmable coefficients
7.
Up/down sampling between YCbCr 4:4:4 and YCbCr 4:2:2
8.
Dither for conversion from 12-bit/10-bit to component to 10-bit/8-bit
9.
Support Gammat Metadata packet
10. Digital audio output interface supporting:
o Up to four I2S interface supporting 8-channel audio, with sample rates of 32~192
kHz and sample sizes of 16~24 bits
o S/PDIF interface supporting PCM, Dolby Digital, DTS digital audio at up to 192kHz
frame rate
o Optional support for 8-channel DSD audio up to 8 channels at 88.2kHz sample rate
o Support for high-bit-rate (HBR) audio such as DTS-HD and Dolby TrueHD through
the four I2S interface or the S/PDIF interface, with frame rates as high as 768kHz
o Automatic audio error detection for programmable soft mute, preventing annoying
harsh output sound due to audio error or hot-unplug
11. Auto-calibrated
input
termination
impedance
6
provides
process-,
voltage-
and
temperature-invariant matching to the input transmission lines.
12. Integrated pre-programmed HDCP keys
13. Intelligent, programmable power management
Table 2-2 lists the supported output video formats:
Table 2-2 Output video formats supported by the HDMI board
Output Pixel Clock Frequency(MHz)
Color
Video
Bus
Hsync/
space
Format
Width
Vsync
RGB
4:4:4
24
30/36
12/15/18
24
4:4:4
30/36
12/15/18
YCbCr
16/20/24
4:2:2
12/15/18
Separate
Separate
Separate
480i
480p
XGA
720p
1080i
SXGA
1080p
UXGA
13.5
27
65
74.25
74.25
108
148.5
162
13.5
27
65
74.25
74.25
108
148.5
13.5
27
65
74.25
74.25
13.5
27
65
74.25
74.25
108
148.5
108
148.5
13.5
27
65
74.25
74.25
Separate
13.5
27
65
74.25
74.25
Separate
13.5
27
74.25
74.25
148.5
Embedded
13.5
27
74.25
74.25
148.5
Separate
27
54
148.5
148.5
Embedded
27
54
148.5
148.5
162
2.2 Layout and Components
The photo of the HDMI board is shown in Figure 2-1 and Figure 2-2. It indicates the location of
the connectors and key components.
Figure 2-1 HDMI transmitter and receiver on the front of the HDMI board
7
Figure 2-2 On the back of the HDMI board with HSTC connector and HDMI ports
The THDB-HDMI board includes the following key components:
Receiver (U3)
Receiver port 1/2 (J2/J3)
Transmitter (U6)
Transmitter port (J4)
27MHZ OSC (Y1)
HSTC expansion connector (J1)
Receiver I2C EEPORM (U4/U5)
RX Regulator (REG1)
TX Regulator (REG2)
Level shifter (U2)
2.3 Block Diagram of HDMI Signal Transmission
This section describes the block diagram of HDMI signal transmission.
Figure 2-3 shows the block diagram of HDMI signal transmission. Please refer to the schematic
included in the CD for more details. The HDMI transmitter is controlled through I2C interface,
where the host works as master and the transmitter works as a slave. Because the pin PCADR is
pulled low, the transmitter I2C device address is set to 0x98. Through the I2C interface, the host
board can access the internal registers of transmitter to control its behavior.
8
Figure 2-3 The block diagram of the HDMI signal transmission
The host can use reset pin TX_RST_N to reset the transmitter, and listen to the interrupt pin
TX_INT_N to detect change of the transmitter status. When interrupt happens, the host needs to
read the internal register to find out which event is triggered and perform proper actions for the
interrupt.
Here are the steps 1-2-3 to control the transmitter:
1.
Reset the transmitter from the TX_RST_N pin
2.
Initialize the transmitter through the I2C interface
3.
Polling the interrupt pin INT_N continuously.
If a HDMI sink device is detected (HDP flag is on):
o Read and parse EDID to determine the capacity of the attached HDMI sink device.
o Configure desired output video/audio, including color space and color depth.
o Perform HDCP authentication
o Output video/audio signals to the Video/Audio bus.
Stop video output if a video sink device is removed (HPD flag is off).
Perform proper actions according to various interrupt events.
9
2.4 Block Diagram of HDMI Signal Receiving
This section describes the block diagram of HDMI signal receiving.
Figure 2-4 shows the block diagram of HDMI signal receiving. Please refer to the schematic
included in the CD for more details. The HDMI receiver is controlled through the I2C interface,
where the host works as master and the transmitter works as a slave. Because the pin PCADR is
pulled low, the transmitter I2C device address is set to 0x90. Through the I2C interface, the host
board can access the internal registers of receiver to control its behavior. The receiver can support
two receiving ports, but only one port can be activated at the same time.
Figure 2-4 The block diagram of HDMI signal receiving
The host can use the reset pin RX_RST_N to reset the receiver, and listen to the interrupt pin
RX_INT_N to detect change of the receiver status. When interrupt happens, the host needs to read
the internal register to find out which event is triggered and perform proper actions for the interrupt.
10
Here are the steps to control the receiver:
1.
Reset the receiver from the RX_RST_N pin
2.
Read the EEPROM (EDID) to check whether the EEPROM contents need to be updated.
When writing data to EEPROM, remember to pull-low the EEPROM write protection pin
EDID_WP. Finally, make sure EDID_WP is pulled high and configure the both I2C pins as
input pins, so the attached HSTC source device can read the EDID successfully.
3.
Initialize the receiver through the I2C interface
4.
Pull-Low the RX1_HPD_N and RX2_PHD_N pins to enable HPD pins of receiving ports.
5.
Set receiver port 1 as active port.
6.
Polling the interrupt pin RX_INT_N. Switch to another receiver port every three seconds and
activate it if no HDMI source device found on the current active port.
If a HDMI source device is detected:
o Perform HDCP authentication.
o Read the input video format, including color space and color depth.
o Configure input and output color space.
Perform proper actions according to various interrupt events.
2.5 Generate Pin Assignments
This section describes how to automatically generate a top-level project, including HDMI pin
assignments.
Users can easily create the HDMI board pin assignments by utilizing the DE3_System Builder V
1.3.1 or later. Here are the procedures to generate a top-level project for THDB-HDMI.
1.
Launch DE3-System Builder
2.
Add a DE3 board. Enable the HSTC-C connector and type desired pin pre-fix name in the
dialog of DE3 Configuration.
11
3.
Add HDMI Board.
4.
Connect DE3 and HDMI Board by drag-and-drop the mouse.
12
5.
Click “Generate” to generate the desired top-level and pin assignments for a HDMI project.
2.6 Pin Definition of HSTC Connector
This section describes pin definition of the HSTC interface onboard.
All the control and data signals of HDMI transmitter and receiver are connected to the HSTC
connector, so users can fully control the HDMI daughter board through the HSTC interface. Power
is derived from 3.3V and 5V pins of the HSTC connector. Figure 2-4 shows the physical pin
location and signal name on the HSTC connector.
13
14
15
Figure 2-5 HSTC Connector of HDMI board
16
The table below lists the HSMC signal direction and description.
Note. The power pins are not shown in the table.
Table 2-3 The HSTC pin definition of the THDB-HDMI board
Signal Name
Pin
Direction
Description
RX_I2S[3]
Number
3
(FPGA View)
input
RX_SCK
4
input
RX_WS
5
input
RX_MCLK
RX_RD[0]
RX_GD[10]
RX_GD[11]
RX_GD[9]
RX_RD[2]
RX_GD[8]
RX_RD[1]
RX_GD[7]
RX_RD[4]
RX_HPD[1]
6
9
10
11
12
15
16
17
18
21
22
input
input
input
input
input
input
input
input
input
input
output
RX_RD[3]
RX_CEC[1]
23
24
input
inout
RX_I2S[1]
27
input
RX_RST_N
RX_I2S[2]
28
29
input
input
RX_SCDT
30
input
RX_SPDIF
33
input
RX_INT_N
RX_I2S[0]
34
35
input
input
RX_RD[11]
36
input
17
I2S serial data output, doubles as DSD
Serial Right CH2 data
output
I2S serial clock output, doubles as DSD
clock
I2S word select output, doubles as DSD
Serial Right CH0 data
output
Audio master clock
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Enable Hardware Plug Detection for
HDMP Port 1, Low Active
Digital Video Output Pins.
CEC (Consumer Electronics Control) for
HDMI Port 1
I2S serial data output, doubles as DSD
Serial Right CH1 data
output
Hardware reset pin. Active LOW
I2S serial data output, doubles as DSD
Serial Left CH2 data
output
Indication for active HDMI signal at input
port
S/PDIF audio output, doubles as DSD
Serial Left CH2 data
output
Interrupt output. Default active-low
I2S serial data output, doubles as DSD
Serial Left CH0 data
output
Digital Video Output Pins.
RX_MUTE
39
input
RX_RD[10]
RX_DSD
RX_RD[9]
RX_RD[8]
RX_RD[7]
RX_RD[6]
RX_RD[5]
EDID_WP
RX_GD[3]
RX_GD[1]
RX_GD[5]
RX_GD[2]
RX_GD[6]
RX_GD[0]
RX_GD[4]
RX_BD[10]
RX_PCLK
RX_BD[8]
RX_BD[11]
RX_BD[9]
RX_BD[3]
RX_BD[2]
RX_BD[1]
RX_DE
RX_BD[0]
RX_PCSDA
40
41
42
45
46
48
52
53
54
57
58
59
60
63
64
65
66
69
70
71
72
75
76
77
78
81
input
input
input
input
input
input
input
output
input
input
input
input
input
input
input
input
input
input
input
input
input
input
input
input
input
inout
RX_HS
RX_BD[4]
RX_PCSCL
82
83
84
output
input
inout
RX_DDC_SDA[1]
RX_EVENODD
87
88
inout
input
RX_DDC_SCL[1]
RX_VS
RX_DDC_SDA[0]
RX_BD[5]
RX_DDC_SCL[0]
RX_BD[6]
RX_HPD[0]
89
90
93
94
95
96
99
inout
output
Inout
Input
Inout
input
output
RX_BD[7]
TX_GD[8]
RX_CEC[0]
100
101
102
Input
output
inout
Mute output, doubles as DSD Serial
Right CH3 data output
Digital Video Output Pins.
DSD Serial Left CH3 data output
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
EEPROM Write Protection
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Output data clock.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Digital Video Output Pins.
Data enable
Digital Video Output Pins.
Serial Programming Data for chip
programming
Horizontal sync. signal
Digital Video Output Pins.
Serial Programming Clock for chip
programming
DDC I2C Data for HDMI Port 1
Indicates whether the current field is
Even or Odd for interlaced format
DDC I2C Clock for HDMI Port 1
Vertical sync. signal
DDC I2C Data for HDMI Port 0
Digital Video Output Pins.
DDC I2C Clock for HDMI Port 0
Digital Video Output Pins.
Enable Hardware Plug Detection for
HDMP Port 0, Low Active
Digital Video Output Pins.
Digital video input pins.
CEC (Consumer Electronics Control) for
18
TX_GD[9]
TX_GD[10]
TX_RD[0]
TX_GD[11]
TX_RD[3]
TX_RD[1]
TX_RD[6]
TX_RD[2]
TX_RD[8]
TX_RD[4]
TX_RD[9]
TX_RD[5]
TX_RD[7]
SDA
SCL
TX_RD[11]
TX_GD[6]
TX_RD[10]
TX_GD[5]
TX_GD[7]
TX_GD[4]
TX_PCSCL
TX_PCSDA
TX_RST_N
TX_GD[3]
TX_INT_N
TX_GD[2]
TX_DSD_L[3]
TX_GD[1]
TX_DSD_R[3]
TX_GD[0]
TX_DSD_L[2]
TX_BD[11]
TX_DSD_R[2]
TX_BD[10]
TX_DSD_L[1]
TX_BD[9]
TX_DSD_R[1]
TX_PCLK
TX_DSD_L[0]
TX_BD[8]
TX_DSD_R[0]
TX_BD[7]
TX_DCLK
TX_BD[6]
TX_SCK
105
106
107
108
111
112
113
114
117
118
119
120
123
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
HDMI Port 0
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
I2S serial data for on-board EEPROM
I2S serial clock for on-board EEPROM
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
Digital video input pins.
I2C Clock for DDC
I2C Data for DDC
Hardware reset pin. Active LOW
Digital video input pins.
Interrupt output. Default active-low
Digital video input pins.
DSD Serial Left CH3 data input
Digital video input pins.
DSD Serial Right CH3 data input
Digital video input pins.
DSD Serial Left CH2 data input
Digital video input pins.
DSD Serial Right CH2 data input
Digital video input pins.
DSD Serial Left CH1 data input
Digital video input pins.
DSD Serial Right CH1 data input
Input data clock
DSD Serial Left CH0 data input
Digital video input pins.
Digital video input pins.
Digital video input pins.
DSD Serial audio clock input
Digital video input pins.
I2S serial clock input
output
output
output
output
output
output
output
output
output
output
output
output
output
inout
output
output
output
output
output
output
output
output
inout
output
output
input
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
19
TX_BD[5]
TX_WS
TX_BD[4]
TX_MCLK
TX_BD[3]
TX_I2S[0]
TX_BD[2]
TX_I2S[1]
TX_BD[1]
TX_I2S[2]
TX_BD[0]
TX_I2S[3]
TX_DE
TX_VS
TX_HS
TX_SPDIF
TX_CEC
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
output
inout
Digital video input pins.
I2S word select input
Digital video input pins.
Audio master clock input
Digital video input pins.
I2S serial data input
Digital video input pins.
I2S serial data input
Digital video input pins.
I2S serial data input
Digital video input pins.
I2S serial data input
Data enable
Vertical sync. signal
Horizontal sync. signal
S/PDIF audio input
CEC (Consumer Electronics Control)
20
Chapter 3
Demonstration
This chapter illustrates the video/audio demonstration for the HDMI board.
3.1 Introduction
This section describes the functionality of the demonstration briefly.
This demonstration shows how to use DE3 to control the HDMI board. The demonstration includes
two parts:
Transmission-Only:
Generate HDMI Video/Audio signal for transmission, including various video formats and color
space. There are 11 video formats available. The color space includes RGB444, YUV422, and
YUV444.
Loopback:
Loopback (Internal bypass) the HDMI Video/Audio Signals. The audio and video output pins of the
receiver are directly connected to the input audio and video pins of the transmitter.
3.2 System Requirements
The following items are required for transmission-only and loopback demonstrations.
Transmission-Only
THDB-HDMI x 1
DE3 Board x 1
LCD monitor with at least one HDMI input x 1
21
HDMI Cable x 1
Loopback
THDB-HDMI x 1
DE3 Board x 1
LCD monitor with at least one HDMI input x 1
HDMI Source Device x 1
HDMI Cable x 2
3.3 Setup the Demonstration
Figure 3-1 and Figure 3-2 show how to setup hardware for transmission and loop-back
demonstrations, respectively.
Transmission Only
HDMI Cable
Figure 3-1 HDMI Transmission-Only Demonstration Setup
Loopback
22
Video in
HDMI Cable
Figure 3-2 HDMI Loopback Demonstration Setup
3.4 Operation
This section describes the procedures of running the demonstration.
FPGA Configuration
Please follow the steps below to configure the FPGA.
Make sure hardware setup is completed.
Connect PC and DE3 with a USB cable.
Power on DE3.
Make sure Quartus II is installed on your PC.
Execute the batch file hdmi_demo.bat under the folder “examples\DE3_xxx_TX_RX\demo
batch”.
HDMI Transmission-Only
After FPGA is configured, please follow the steps below to run the HDMI transmission-only
demonstration.
Connect the HDMI LCD monitor and the HDMI transmitting port with a HDMI cable.
Power on the LCD monitor and make sure the LCD monitor is set to the mode where HDMI
input is the source. Please refer to the user manual of your HDMI Display for more details.
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When LCD monitor is detected, the LED2 of DE3 will be turned on.
After approximately 10 seconds, a test pattern will be displayed on the LCD monitor. The first
displayed pattern is 480p (720x480p60) pattern.
Press “BUTTON0” to change test patterns. Please refer to Table 4-2 for built-in test patterns.
There are eleven built-in test patterns available in this demonstration. You will not be able to see all
the test patterns if your LCD monitor doesn’t support such resolution.
Press “BUTTON1” to change the color space of pattern source. The color space includes
RGB444, YUV422, and YUV444.
Figure 3-3 and Figure 3-4 show the test pattern of FULL HD (1920x1080p60) in RGB and YUV
color space, respectively.
It will take approximately 10 seconds to display a new pattern on the LCD when users change test
pattern or color space.
Figure 3-3 FULL HD in RGB444 Color Space
Figure 3-4 FULL HD in YUV Color Space
Figure 3-5 shows the NIOS program trace log when a HDMI LCD monitor is detected. It indicates
the LCD monitor in use supports color space YUV444 and YUV422, but not RGB444. Various
video formats supported are listed according to Video Identify Code (VIC). The format of input and
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output color of the transmitter is RGB444 and RGB444, respectively. It implies there is no change
of color format in between.
Figure 3-5 NIOS program trace log of transmitting-only demonstration
HDMI Internal Loopback
After FPGA is configured, please follow the steps below to run the HDMI loopback demonstration.
Connect the HDMI LCD and the HDMI TX port with a HDMI Cable.
Power on the LCD monitor and make sure the LCD monitor is set to the mode where HDMI
input is the source.
Connect the HDMI source device and HDMI RX port with a HDMI Cable.
Power on the HDMI source device and make sure its HDMI port is selected as the output.
Users will be able to see the video displayed on the LCD monitor and hear the sound, if there is
a speaker built-in.
Users can change the RX port connected to the HDMI source device. The demonstration can
automatically detect the RX port and activate it.
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Figure 3-6 shows the NIOS program trace log when a HDMI LCD source device is detected. It
indicates the input video resolution is 1280 x 720 (VIC=4) with color space RGB444 and 36-bits
color depth.
Both input color and output color of the receiver and transmitter are configured as RGB444. In
another words, the color format doesn’t change from the source to the LCD monitor during the
loopback process. The output color depth of the transmitter is configured as 24-bits.
Figure 3-6 NIOS program trace log of loopback demonstration
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Chapter 4
Case Study
This chapter describes the design concepts for the HDMI demonstration in the previous chapter.
4.1 Over view
This section describes the overview of the reference design.
This reference design shows how to use DE3 to control HDMI board. Please refer to the pervious
chapter for the demonstration of this reference design.
The source code of the reference design can be found in the THDB-HDMI CD under the directory
of Examples folder. The demonstration includes the following two major functions:
Transmission only:
Generate HDMI Video/Audio signals for transmission, including various video formats and color
space. There are 11 video formats available. The color space includes RGB444, YUV422, and
YUV444.
Loopback:
Loopback (internal bypass) the HDMI Video/Audio Signals. The audio and video output pins of the
receiver are directly connected to the input audio and video pins of the transmitter.
4.2 System Function Block
This section will describe the system behavior in function blocks.
Figure 4-1 shows the system function block diagram of this demonstration. In the design, SOPC is
included because NIOS II processor is used to control both transmitter and receiver through I2C
interface.
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The NIOS program is designed to run on the on-chip memory. A customized I2S controller is
designed to generate I2S 48K stereo audio for the HDMI transmitting-only mode. The audio data is
stored in the on-chip memory and sent to the HDMI transmitter by NIOS II processor.
The video pattern generator is designed to generate test patterns for HDMI transmitter-only mode. It
provides eleven video formats in three color spaces. The source selector circuit is designed to select
the desired video source between the video pattern generator and the video from the receiver. Four
LEDs and two BUTTONs on DE3 are used for human interface. BUTTONs are designed to change
the test pattern and associated color space for transmission. LEDs are designed to indicate the
HDMI status, which is illustrated in Table 4-1. BUTTONs are designed to change the video format
and color space of the build-in video pattern generator, which is illustrated in Table 4-2.
Figure 4-1 System Function Block Diagram
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Table 4-1 LED Indications
LED
Description
System is running.
HDMI sink device is detected and synchronized.
HDMI source device is detected and synchronized.
Table 4-2 Button Operation Definition
BUTTON
Description
Press to change active video format of the built-in
video pattern generator.
Press to change active video color space of the
built-in video pattern generator.
Transmitter Controlled by NIOS II Processor
The transmitter is controlled by NIOS program through I2C interface. Based on I2C protocol, the
NIOS program can read/write the internal registers of the transmitter, and control the behavior of
the transmitter. The NIOS program controls the transmitter to perform the following procedures step
by step:
o Initialize the HDMI chip.
o Detect if a HDMI sink device is attached or detached, e.g. LCD Display.
o Read and parse the EDID content to find the capability of the HDMI sink device.
The capability includes supported color space, video format (VIC code), and color
depth etc.
o Perform HDCP authentication.
o Configure the color space of input and output. The transmitter offers color space
transformation and outputs RGB444, YUV422, or YUV444
o Configure the color depth of output video.
o Send VIC to the video sink device.
o Configure the audio interface and format of output video.
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Receiver Controlled by NIOS II Processor
The receiver is controlled by NIOS program through I2C interface. Based on I2C protocol, the
NIOS program can read/ write the internal registers of the receiver, and control the behavior of the
receiver. The revision number of receiver is either A1 or A2, which can be determined by querying
the register 4 of receiver.
The major differences between both revisions are:
1.
Receiver initialization process
2.
Video synchronization process.
Please search the global variable “Is_A2” in it6605.c for detail information.
The NIOS program controls the receiver to perform the following procedures step by step:
o
o
o
o
Initialize the HDMI receiver chip.
Detect if a HDMI source device is attached or detached.
Select one of the receiving ports and activate it.
Read and parse the EDID content to find the capability of the HDMI source device.
The capability includes supported color space, video format (VIC code), and color
depth etc.
o Perform HDCP authentication.
o Report the input video (VIC) and audio format of the attached HDMI source device.
o Configure the color space of input and output. The receiver can provide color space
transformation.
Video Pattern Generator
The video pattern generator is designed to generate test pattern for HDMI transmitting-only mode.
The supported video formats are listed in Table 4-2.
Video Format
720x480p60
1024x76pP60
1280x720p50
1280x720p60
1280x1024
1920x1080i60
1920x1080i50
1920x1080p60
1920x1080p50
VIC
3
19
4
5
20
16
31
30
PCLK (MHZ)
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65
74.25
74.25
108
74.25
74.25
148.5
148.5
1600x1200p5
1920x1080i120
46
162
148.5
It also supports three color spaces, which are RGB444, YUV422, and YUV444.
The required PCLK is generated from Megafunction ALTPLL and ALTPLL_RECONFIG IP. The
required PLL-reconfigure data is stored in on-chip ROMs.
Video Source Selector
The source selector is implemented using Megafunction LPM_MUX.
4.3 NIOS Program
This section describes the design flow and how Nios II processor controls transmitter and receiver.
Figure 4-2 shows the software stack of the NIOS program. The I2C block implements the I2C
read/write functions based on GPIO system call. The HDMI transmitter block and receiver block
are referred as the HDMI driver. The HDMI transmitter chip and receiver chip are managed and
controlled through the I2C protocol. The I2S driver block is in charge of sending audio data to the
transmitter.
Figure 4-2 Software Stack
Figure 4-3 shows the file list of the NIOS program. The control center is located in main.c. The
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beep.c includes audio raw data for generating a tone sound. The folder named terasic_lib includes
the I2C driver. The folder named HDMI_Lib includes transmitter and receiver drivers. The
platform-dependent functions are located in mcu.c under HDMI_Lib.
Figure 4-3 NIOS Program File List
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System Configuration
To use the HDMI library in NIOS II, the const _MCU_ should be defined in the configuration
settings, as shown in Figure 4-4. Two on-chip memories are created to store the NIOS program and
data separately. The size of each on-chip memory is 128 K bytes. One on-chip memory is used to
store program and the other one is used to store data. The option “Small C Library” must be enabled
to reduce the size of the program. The associated configuration is shown in Figure 4-5
Figure 4-4 Define _MCU_ constant
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Figure 4-5 Configuration of System Library
Audio Test
If users would like to test audio during HDMI transmitting-only mode, please remove the constant
definition TX_VPG_COLOR_CTRL_DISABLED from main.c. Users will hear a tone sound from
the built-in speaker of HDMI LCD monitor when pressing BUTTON1 of DE3 board.
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Chapter 5
Appendix
5.1 Revision Histor y
Revision
Date
Change Log
1.0
DEC 02 2008
Initial Version
1.1
APR 06 2009
Support Receiver Revision A2
1.2
JAN 04 2010
Figure 2-1 Corrected
1.3
MAR 09 2011
Support HDMI 1.4
1.4
AUG 01 2017
Contact Information
5.2 Always Visit THDB-HDMI Webpage for Update
We will be continuing providing interesting examples and labs on our THDB-HDMI web page.
Please visit www.altera.com or hdmi.terasic.com for more information.
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