Checking Error Codes - Mitsubishi FX3U-USB-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
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8.5

Checking Error Codes

8.5.1 Error codes when NAK is sent
The table below shows error codes and contents of errors when NAK is sent in communication between the
computer and a PLC.
As an error code, a two-digit ASCII code (hexadecimal) within the range from 00H to FFH is sent.
When two or more errors occur at the same time, priority is given to the error code with the smallest number,
and the error code with the smallest number is sent.
When any error shown below occurs, the entire transfer sequence is initialized.
Error code list
Error code
(hexadecimal)
02H
03H
06H
07H
0AH
10H
18H
D-84
Error item Contents of error
Sum check error has occurred.
Sum check The sum check code included in the
error received data is different from the sum
value calculated from the received data.
The communication protocol is
abnormal.
A control procedure set using
parameters was ignored, and a different
control procedure was adopted in
Protocol error
communication. Or the adopted control
procedure was partially different from the
preset control procedure. Or a command
specified in the preset control procedure
does not exist.
An error occurred in the character area
A, B or C. Or a specified command does
not exist.
1) The control procedure set using
parameters is different.
Character
area error
2) A specified device number does not
exist in the target PLC.
3) A device number is not set with the
specified number of characters (5 or
7 characters).
Character ASCII code data to be written to a device
error is not hexadecimal.
PLC number A station with the corresponding PLC
error number does not exist.
PLC number A station with the corresponding PLC
error number does not exist.
Remote control to set the RUN or STOP
mode is disabled.
Remote
The RUN or STOP mode is determined
control error
in the PLC hardware (by using the RUN/
STOP selector switch, etc.).
8 Troubleshooting
8.5 Checking Error Codes
Action
Check the data sent from the computer
and the contents of the sum check.
Modify either one, and then execute
communication again.
1) Check the contents of parameters
and the contents of control
procedure. Modify either contents,
and then execute communication
again.
2) Refer to the command list shown in
Chapter 7, modify the specified
command etc., and then execute
communication again.
1) Check the contents of the character
areas A, B and C, modify the
contents if necessary, and then
execute communication again.
2) Refer to "2.2.2 Applicable device
ranges", modify the number of
characters used to specify the device
number, and then execute
communication again.
Check the data to be written to the
device, modify it if necessary, and then
execute communication again.
Check the PLC number included in the
message, modify it if necessary, and
then execute communication again.
The PLC number should be "FFH" in all
FX Series PLCs.
Check the PLC number included in the
message, modify it if necessary, and
then execute communication again.
The PLC number should be "FFH" in all
FX Series PLCs.
Set the PLC mode to RUN or STOP
using the forced RUN mode.