Errors In Communication Using Mc Protocol - Mitsubishi MELSEC-F User Manual

11 TROUBLESHOOTING

11.5.3 Errors in communication using MC protocol

Communication error
Check the open status of the
connection with the external device.
Are the corres-
ponding connection LEDs
(C1-C8) lit?
YES
Was a command sent
form the external device?
YES
Was a response
returned to the device that sent
the command?
YES
Is the end code of
the response "0"?
YES
1)
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NO Execute the open processing of the
applicable connection. (For details,
see Section 5.6.)
NO
Send the command to the Ethernet
module.
NO
Is the IP address
designation of the command
correct?
Does the
communication protocol
(TCP/UDP) match with that of the
external device?
The command may not be sent to the
Ethernet module from the external
device on the command sending
side. Check the sending side.
Fix the faulty part according to
NO
the description of the end and
abnormalcodes (see Section 11.4).
NO
Correct the IP address and send
the command again.
YES
Match the communication protocol
NO
(TCP/UDP) with the external device.
(For details, see Section 5.5.)
YES
MELSEC-F
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