Modbus Device Assignment Function - Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual

MODBUS device assignment function

This function automatically converts the access to the MODBUS devices of the RJ71EN71 and RnENCPU (network part) into
the access to the devices of the CPU module.
Use the MODBUS device assignment parameters to create the association between the MODBUS devices and the device
memory areas of the CPU module.
This allows the RJ71EN71 and RnENCPU (network part) to convert the access to the MODBUS device specified in the
request message from the MODBUS/TCP master device into the access to the corresponding device of the CPU module.
CPU module
Device memory
D300 1234H
(1) Request message (request for reading the value in holding register 400500)
(2) Response message (response with the value in holding register 400500 (1234H))
Setting procedure
Set the assignment to the MODBUS devices in "MODBUS/TCP Settings" under "Application Settings".
For details, refer to the following.
Page 254 MODBUS/TCP Settings
RJ71EN71
MODBUS device assignment parameter
Device memory MODBUS device
D299 400499
D300 400500
D301 400501
MODBUS/
TCP master device
(1)
(2)
1 FUNCTIONS
1.7 Communications Using MODBUS/TCP
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