Command Message; Header (Start Code); Unit Numbe; Check Code - Panasonic FP0R User Manual

Format of command and response

Command message

All command-related items should be noted in the text segment. The unit number must be specified
before sending the command.

1. Header (Start code)

Commands must always have a "%" (ASCII code: H25) or a "<" (ASCII code: H3C) at the beginning of a
message.
2. Unit number
The unit number of the PLC to which you want to send the command must be specified. In 1:1
communication, the unit number "01" (ASCII code: H3031) should be specified. The unit number of the
PLC is specified by the system register.
3. Text
The content differs depending on the command. The content should be noted in all upper-case
characters, following the fixed formula for the particular command.

4. Check code

BCC (block check code) for error detection using horizontal parity. The BCC should be created so that it
targets all of the text data from the header to the last text character.
The BCC starts from the header and checks each character in sequence, using the exclusive OR
operation, and replaces the final result with character text. It is normally part of the calculation program
and is created automatically.
The parity check can be skipped by entering "* *" (ASCII code: H2A2A) instead of the BCC.
5. Terminator (End code)
Messages must always end with a " C R " (ASCII code: H0D).
Note: When writing
The method for writing text segments in the message varies depending on the type of command.
-
If there is a large number of characters to be written, they may be divided and sent as several
-
commands, if there is a large number of characters in the value that was loaded, they may be divided
and several responses sent.
Key Point:
With the FP0R, an expansion header "<" is supported to send single frame of up to 2048 characters as
-
well as general "%".
Type of header
%
<
No. of characters that can be sent in 1 frame
Max. 118 characters
Max. 2048 characters
7-9