Datalogic GWY-01-PBS-01, Reference Manual

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COMMAND PROTOCOL
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4
4.2 CBX - COMMAND PACKET STRUCTURE
Below is the packet structure of a standard CBx command.
Word # Command Packet Element MSB LSB
01 Overall Length : 2-byte value indicating
the number of “ words ” in the command
packet. This value will always be at least 6
words.
0x00 0x06 + (number
of any additional
words)
02 Command ID : 0xAA + 1-byte value
indicating command to perform.
0xAA <Command ID>
03 0x00 in MSB, Node ID in LSB 0x00 <Node ID>
04
Timeout Value : 2-byte integer for the
length of time allowed for the completion of
the command, measured in 1 millisecond
units, where
0x07D0 = 2000 x .001 = 2
seconds.
0x07 0xD0
05 Start Address : 2-byte integer indicating
the location of tag memory where a
Read/Write operation will begin (when
applicable).
<Start MSB> <Start LSB>
06 Block Size : 2-byte integer indicating the
number of bytes that are to be read from or
written to a tag beginning at the specified
Start Address (when applicable).
<Length
MSB> <Length LSB>
07 Additional Data Byte Values 1 & 2 : holds
2 bytes of data used for fills, writes, etc.
(when applicable)
<D1> <D2>
08 Additional Data Byte Values 3 & 4 :
(when applicable)
<D3> <D4>
Table 3: CBx Command Packet Structure