Mitsubishi FX3U-422-BD - Checking Absence;Presence of Data Transfer Errors

B-46
FX Series PLC User's Manual - Data Communication Edition
N:N Network
9 Troubleshooting
9.6 Checking Absence/Presence of Data Transfer Errors
2. Checking setting errors
1) Error flags
If the parameter setting includes an error, the serial communication error flag turns ON.
Verify that the devices shown in the table below are ON.
When using the N:N Network on ch 1, check M8063.
When using the N:N Network on ch 2, check M8438.
2) Error codes
When the serial communication error flag turns ON, the error code is stored in the device specified in the
table below.
The serial communication error flags and serial communication error codes are not cleared even when
communication is restored.
Serial communication errors are cleared in FX
3G, FX3U and FX3UC PLCs when the power is turned off
and on.
Serial communication errors are cleared in other PLCs when the mode is switched from STOP to RUN.
9.6 Checking Absence/Presence of Data Transfer Errors
Verify that link errors have not occurred in the master station and slave stations. Link errors can be checked
using the flags specified below.
9.6.1 Check while data transfer sequence is being executed
While the N:N Network is being executed, the data transfer sequence ON flag remains ON.
Verify that the device specified in the table below is ON.
9.6.2 Checking data transfer sequence errors
When a link error occurs in the master station or slave station, the data transfer sequence error flag turns ON.
The data transfer sequence error flag varies depending on the FX Series and station number. Refer to the
table below.
Device Name Description
M8063 Serial communication error 1 (ch 1)
Turns ON when abnormality occurs during serial communication
using ch 1.
M8438 Serial communication error 2 (ch 2)
Turns ON when abnormality occurs during serial communication
using ch 2.
Device Name Error code Description
D8063 Serial communication error code 1 (ch 1) 6308
N:N Network parameter setting error
D8438 Serial communication error code 2 (ch 2) 3808
FX Series Device Name Description
FX
1N, FX2N, FX3G,
FX3U, FX1NC, FX2NC,
FX
3UC
M8191
Data transfer sequence ON flag
Remains ON while data transfer is being
executed.
FX
0N, FX1S M503
FX Series
Master
station
Slave
station
No. 1
Slave
station
No. 2
Slave
station
No. 3
Slave
station
No. 4
Slave
station
No. 5
Slave
station
No. 6
Slave
station
No. 7
FX
1N, FX2N, FX3G,
FX3U, FX1NC, FX2NC,
FX
3UC
M8183 M8184 M8185 M8186 M8187 M8188 M8189 M8190
FX
0N, FX1S M504 M505 M506 M507 M508 M509 M510 M511