Check Items - Mitsubishi FX3U-USB-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Non-Protocol Communication (FX
7. Troubleshooting
7.1

Check Items

1) Check the POWER LED of the 232IF.
- While the POWER LED is ON, the drive power is being supplied normally.
- If the POWER LED is OFF, the drive power is not being supplied normally.
2) Verify that the power supply is correctly wired to terminals of the 232IF.
3) Check the SD LED and RD LED of the 232IF.
- If the RD LED does not turn ON when the 232IF receives data or if the SD LED does not turn ON when
the 232IF sends data, check the connection and wiring.
- If the RD LED turns ON when the 232IF receives data or if the SD LED turn ON when the 232IF sends
data, the installation and wiring are normal.
4) Verify that the communication setting (BFM #0) in the 232IF is aligned correctly with the communication
setting in the external equipment. If the communication setting is not aligned correctly, align it.
5) Check the timing at which data is sent and received. For example, when sending data, verify that the
external equipment is ready to receive.
6) When the terminator is not used, verify that the quantity of data to be sent matches the receivable data
quantity. If the quantity of send data may vary, use the terminator.
7) Verify that the external equipment is operating normally.
8) Verify that the adopted data format is uniform. If the data format is different, modify it.
7.2 Error Codes
When an error occurs while data is being sent or received, the 232IF sets bit 3 of the BFM #28 to ON,
and stores the corresponding error code to the BFM #29 .
Code
0 No error
Receiving parity error, overrun
1
error or framing error
2 Undefined
3 Defective received character
4 Receiving sum check error
Receive data buffer overflow
5 (only in interlink connection
mode)
6 Baud rate setting error
7 Receiving CR error
8 Receiving LF error
Head sending/receiving
9
terminator setting error
10 Receiving terminator error
11 Undefined
12 Transmission order error
-232IF)
2N
Contents
The communication format such as the baud rate does not agree.
The control timing does not agree.
The received data is not ASCII code.
The sent sum does not agree with the received sum result (BFM #16).
The number of received bytes exceeds "512+30" bytes. Decrease the
maximum number of receivable bytes (BFM #2), and increase the pre-
liminary receive data buffer area.
Non-existing baud rate is specified.
CR is not located in the specified position.
LF is not located in the specified position.
The head terminator is something other than 01H to 1FH.
The terminator is not located in the specified position. Or the terminator
does not agree.
The transmission order does not agree.
Cause and countermeasures
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7 Troubleshooting
7.1 Check Items
A
B
C
D
E
F
G
H
I
Apx.
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