User`s manual

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(4) Variable data
"Variable data" is the generic term for the following data.
These variable data can be handled as part of a user frame.
• Sum check code whose objective is an arbitrary range in the transmit and receive messages.
• Horizontal parity code whose objective is a determined range in the transmit and receive messages.
• Two's complement sum check code whose objective is a determined range in the transmit and receive
messages.
• Q series C24 station No.
• One byte data in data transmission (NULL: Code 00H) One byte of arbitrary data in data reception. (Used to
handle an arbitrary byte of data as part of the user frame during receiving check by the Q series C24.)
(a) Variable data designation method
Variable data is designated by combining write code FFH and the data codes shown in the table below.
The sum check code, Q series C24 station No., and other variable data can be handled according to FFH of the
first byte and 00H to FFH of the second byte.
FFH
1st byte
2nd byte
00H to FFH