Modbus(R) Device Assignment Function - Mitsubishi QJ71MB91 User Manual

5
FUNCTIONS

5.3.2 MODBUS(R) device assignment function

The MODBUS
(QJ71MB91) MODBUS
This allows direct access from the MODBUS compatible master device to the
programmable controller CPU device memory.
Supporting the MODBUS
memories of the programmable controller CPU to be assigned.(
(1) MODBUS
Set the MODBUS
The following settings are possible for the MODBUS
parameters.
(a) Correlating the MODBUS
Programmable
QJ71MB91 (Slave function)
controller CPU
No sequence
program required
MODBUS device assignment parameter
Device memory
Device
1234
D300
H
Figure 5.13 MODBUS
device assignment function automatically converts access to a slave
device into access to a programmable controller CPU device.
devices of large capacity, the QJ71MB91 allows all device
device assignment parameter setting
device assignment parameters to the slave (QJ71MB91).
memory.
When a message requesting an action such as write coil is received from the
master, the access to the MODBUS
access to the programmable controller CPU device.(
7.3.3)
R
MODBUS device R
D299 400499
D300 400500
D301 400501
RS-232, RS-422 or RS-485
device and programmable controller CPU device
device to the programmable controller CPU device
device is automatically converted into
Request message (Write 1234
register 400500)
5.3 Slave Function
5.3.2 MODBUS(R) device assignment function
Section 7.3.1)
device assignment
Section 7.3.1 to Section
MODBUS R
Master
device
to holding
H
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