BenQ Q7T4-FP71G Service Manual page 6

Q7T4-FP71G LCD Monitor Service Guide
Note A: Byte4 (cksum) = Byte1 + Byte2 + Byte3
Note B: Data = The value write to MCU or EEPROM
Note C: XX = don't care, any value (<=0xFF).
When PC Host sends 0x7D command to MCU, MCU must return as following (2 bytes)
Return Code
Checksum error code
Normal return code
If normal return code is exact FCh
R-Byte1
FC
the above Byte3 (/data)
FC
Confidential
Alignment Procedure
R-Byte2
AA
FC
CF
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