Panasonic FP0H User Manual page 121

• If no response is returned, the transmission format may not be correct, the
command may not have arrived at the PLC, or the PLC may not be
functioning. Check to make sure all of the communication specifications
(e.g. baud rate, data length, parity) are aligned.
• If the response contains an "!" instead of a "$", the command was not
processed successfully. The response will contain a communication error
code. Check the meaning of the error code.
• Unit number and command name are always identical in a command and its
corresponding response, as indicated below. This makes correspondence
between a command and a response clear.
Command
% 0 1
Same
Response
% 0 1
# R C
Same
$ R C
10.6 MEWTOCOL-COM Format
C
R
C
R
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