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MELSEC-Q
7 PARAMETER SETTING
1) The QJ71MT91 receives a "holding register 400500 read" request
message from the master.
2) The QJ71MT91 reads data from its own buffer memory according to the
value set to the MODBUS
R
device assignment parameter.
Faster processing is executed as access is not influenced by the
sequence scan.
3) The QJ71MT91 creates a response message and sends it to the
master.
POINT
The programmable controller CPU device memory value can be stored in the
QJ71MT91 buffer memory, and the QJ71MT91 buffer memory value can be stored
in the programmable controller CPU device memory.
Data can be stored by either of the following:
Automatic refresh setting on GX Configurator-MB (Refer to Section 8.5)
Transfer using intelligent function module devices (Un\G )
(Refer to QCPU User’s Manual (Function Explanation, Program Fundamentals))