Omron CJ Series Connection Manual page 66

No. Outline
2.3. Normal/error detection
processing
Description
Detects a normal end or an error end of the result of
send/receive processing.
It is considered as a normal end when all the following
conditions are satisfied.
(1)Normal end of PMCR instruction
(No PMCR instruction error)
(2)Normal end of communications sequence
(No communications error)
(3)Normal messages received from Destination Device
(No Destination Device error)
If any of the errors are detected under the conditions
above, a corresponding error flag will turn ON.
9．Program
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