Texas Instruments FPD Link III - DS90UB903Q & DS90UB904Q EVK SERDESUB-21USB/NOPB SERDESUB-21USB/NOPB Data Sheet

Product codes
SERDESUB-21USB/NOPB
Page of 52
 
22 
SERDESUB-21USB User’s Guide  
 
 
 
 
            
 
 
SNLU101 – April 2012 
 
 
 
 
Figure 5. Virtual device addressing from GPU/FPGA I2C controller 
 
 
 
I
2
C Communication over Bi-directional Control Channel in 
Display Mode 
 
This section provides instructions for a simple I2C Read/Write transaction over the bi-
directional control channel validating the interface between the host and Serializer to 
Deserializer.  
 
1)  Check the Serializer DES DEV ID register 0x06 contents 
 
2)  The value entered in Serializer register 0x06 sets the target Deserializer device to 
communicate with. Load the Deserializer slave address register.  
 
3)  Host controller to load and transmit data byte to Deserializer address 0xC0 
 
4)  For verification purposes Deserializer register 0x13 General-purpose register will be 
exercised for reading and writing data. Other Deserializer registers can be 
programmed to check internal functions; such as register 0x03 b[0] RRFB. 
 
5)  Host controller to load and transmit write transaction to register byte 0x13 = 0xFF. 
Note default of register 0x13 = 0x00.  
 
6)  Host controller to read back Deserializer 0xC0 register 0x13 = 0xFF