Modbus Device Assignment Parameter - Mitsubishi Electric QJ71MB91 User Manual

7
PARAMETER SETTING

7.3 MODBUS Device Assignment Parameter

Using MODBUS device assignment parameters, the MODBUS devices are correlated with
the programmable controller CPU device memory.
This allows direct access from the MODBUS compatible master device to the
programmable controller CPU device memory.
Programmable
controller CPU
No sequence
program required
Device
D300 1234H
7
- 11 7.3 MODBUS Device Assignment Parameter
QJ71MB91 (Slave function)
MODBUS device assignment parameter
Device memory
MODBUS device
D299
400499
D300 400500
D301 400501
RS-232, RS-422 or RS-485
Figure 7.6 MODBUS device and programmable controller CPU device
Request message (Write 1234H to holding
register 400500)
MODBUS
Master device