Terasic THDB-HDMI, Руководство пользователя

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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.