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MELSEC-Q
10 DEDICATED INSTRUCTIONS
Error
(1) When the dedicated instruction is completed with an error, the completion
status indication device (D2)+1 turns ON and the error code is stored into the
complete condition (S1)+1.
According to the error code, check the error and take corrective action,
referring to the following manual.
<Error code>
03E8
H
to 4FFF
H
: QCPU User's Manual (Hardware Design, Maintenance and
Inspection)
7300
H
or more : Section 11.3.3 in this manual
(2) If Basic parameter setting request (Y1) turns ON during execution of the
MBREQ instruction, the dedicated instruction is completed with an error.
POINT
(1) In the case of the MBREQ instruction, exception codes and function codes are
not stored in the Error log (address: 0CFE
H
to 0DFF
H
) of the buffer memory.
Check the exception and function codes by the response message that is
stored in the response message storage device.
(2) This instruction is completed normally even if the target slave device gives an
exception response.
When the instruction is completed normally, check the highest-order bit of the
function code in the response message to determine whether the response is
normal or not. (For an exception response, the highest-order bit in the first byte
of the receive data turns ON.)
For an exception response, check the exception code (the second byte of the
receive data) in the response message and take corrective action. (Refer to
Section 11.3.2.)
Program example
The following program is designed to send the request message to write the value OR-
masked with 0008
H
to the holding register 400003 (Mask write register (FC: 22) of the
slave (IP address: 192.1.0.2).
When the I/O signals of the QJ71MT91 are X/Y00 to X/Y1F
