Omron CJ1W-SCU32 Operation Manual page 323

Cause and Assumed cause
correction
In Serial Gateway Mode or Protocol
Macro Mode (RD@/SD@ indicator
flashes):
• The response from the remote
device was too fast, and the data
received by the Serial Communica-
tions Unit was discarded.
• The Serial Gateway Response Tim-
eout Monitoring Time for the
*_P1_PmrSgwRespTimeoutCfg or
*_P2_PmrSgwRespTimeoutCfg
device variable is too short.
During Loopback Test
• Loopback test jig failure.
• Noise
• The communications circuits in the
Serial Communications Unit are
faulty.
A serial gateway cannot interrupt pro-
cessing between protocol macro
steps.
If the message frame is corrupted due
to noise, a response timeout occurred
at the FINS send source if the
*_P1_TimeoutErr or
*_P2_TimeoutErr device variable is
FALSE.
A no-protocol instruction was exe-
cuted when No-protocol Mode was
not set.
Attached Attached information 1: Port number where error was detected
information
Precautions/ None
Remarks
CJ-series Serial Communications Units Operation Manual for NJ-series CPU Unit(W494)
9 Troubleshooting and Maintenance
Correction
• Delay the remote device response.
• Set a longer Serial Gateway
Response Timeout Monitoring Time
in the
*_P1_PmrSgwRespTimeoutCfg or
*_P2_PmrSgwRespTimeoutCfg
device variable.
• Correct any mistakes in wiring the
loopback test jig.
• Implement noise countermeasures.
• Replace the Unit.
Perform retry processing for sending
commands or review the communica-
tions sequence.
Check the noise conditions between
nodes. Increase the setting for the
number of resends in the device that
sent the command. If required, per-
form retry processing for communica-
tions.
Set the serial communications mode
to 3 hex (No-protocol Mode).
Prevention
Perform countermeasures in
advance.
• Check the wiring of the loopback
test jig.
• Use the Unit away from sources of
noise. Implement noise counter-
measures.
Perform countermeasures in
advance.
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