Terasic THDB-HDMI, Руководство пользователя

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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
Initialize the HDMI receiver chip.
o
Detect if a HDMI source device is attached or detached.
o
Select one of the receiving ports and activate it.
o
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.
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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 VIC PCLK (MHZ)
720x480p60 3 27
1024x76pP60 - 65
1280x720p50 19 74.25
1280x720p60 4 74.25
1280x1024 - 108
1920x1080i60 5 74.25
1920x1080i50 20 74.25
1920x1080p60 16 148.5
1920x1080p50 31 148.5