Barco SERIAL COMMUNICATION LCD PROJECTOR, User Manual

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Communication protocol summary
Start byte \xfe
Projector address
Command byte(s)
Data bytes
(OPTIONAL)
Checksum byte
Stop byte \xff
Start byte
The “start byte” informs the projector (in case of transmission) or the computer
(in case of reception) that a new data transfer will take place.
Projector address
The “projector address” defines the address of the projector the computer
wants to talk to (in case of transmission) or the address of the projector that
answers (in case of reception).
The maximum number of projectors that can be addressed by one computer
is 256.
Command byte(s)
There is at least one command byte to define the action to be performed.
Commands that are not often used or complex commands can take more than
one byte.
All command bytes that are sent by the computer to get information out of the
projector are repeated in the answer-data-transfer of the projector.
Data bytes
(OPTIONAL)
Wheather the command bytes are followed by one or more data bytes depends
on the contents of the command bytes.
(Some commands are not followed by data bytes at all !)
Communication protocol summary
Start byte \xfe
Projector address
Command byte(s)
Data bytes
(OPTIONAL)
Checksum byte
Stop byte \xff
Start byte
The “start byte” informs the projector (in case of transmission) or the computer
(in case of reception) that a new data transfer will take place.
Projector address
The “projector address” defines the address of the projector the computer
wants to talk to (in case of transmission) or the address of the projector that
answers (in case of reception).
The maximum number of projectors that can be addressed by one computer
is 256.
Command byte(s)
There is at least one command byte to define the action to be performed.
Commands that are not often used or complex commands can take more than
one byte.
All command bytes that are sent by the computer to get information out of the
projector are repeated in the answer-data-transfer of the projector.
Data bytes
(OPTIONAL)
Wheather the command bytes are followed by one or more data bytes
depends on the contents of the command bytes.
(Some commands are not followed by data bytes at all !)
communication protocol
Chapter 1: Communications basics
communication protocol Chapter 1: Communications basics