RoadRunners – Communication Protocol
TF -
Protocol of communication
4
January 2007
Protocol of communication
1. Bidirectionnal packets
1.1. Generic packet
All frames that are described in the following have to follow the following format of packet. That
is available for communication from the scanner to the host and from the host to the scanner.
1.1.1. Format of that packet
Code ID Size of payload
Command parameter(s)
Event parameter(s)
1 Byte
2 Bytes
N Bytes
1.1.2. Explanations
-
Code ID [1 Byte] :
o
Bits 7:5 is the logical device
o
Bits 4:1 is the command
o
Bit 0: when set, the message must be acknowledged ( => “sequence number” is
required)
The response / Event will have the same code ID as the command.
-
Size of payload [2 Bytes]
o
This is big-endian format
o
This is including the “sequence number byte” if this one is required.
-
Payload [N Bytes] :
o
1 byte for “sequence number” when applicable
Header
Payload
