Barco Projector User Manual page 70

Example :
Read the status of the backlight of the 2 line LCD of a
projector with address \x01. Suppose the backlight is on.
Transmit
Start
Projector address
Command[0]
Command[1]
Checksum
Stop
Receive (acknowledge)
Start
Projector address
Command[0]
Command[1]
Checksum
Stop
Receive (answer)
Start
Projector address
Command[0]
Command[1]
Data[0]
Checksum
Stop
2 line LCD, read backlight
\xfe
\x01
\x7a
\x04
\x7f
\xff
\xfe
\x01
\x00
\x06
\x07
\xff
\xfe
\x01
\x7a
\x04
\x01
\x80
\x00
\xff
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