Omron CJ Series Connection Manual page 83

No. Function
7.5. Error code storage area
setting
Description
When it is determined in 7.4. Normal/Error Determination
Processing that the processing ends normally, #0 is set in the
error code storage area.
When it is determined in 7.4. Normal/Error Determination
Processing that the processing ends in error, the following
values are set in the error code storage area.
•Response code for a response code error
•#F401 for a timeout
•#F402 for a close processing status error
*For information on response codes, refer to 9.7. Error Code
List.
9．Program
80