Mitsubishi QJ71MB91 User Manual

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9.2 Program Example for Normal System Configuration
9.2.3 When using the automatic communication function and the communication by dedicated instructions on the same channel
9
PROGRAMMING
2) Program example for dedicated instruction
This section provides an program example in which a dedicated instruction
(MBRW) is executed while automatic communication of Automatic
communication parameter 1 on channel 2 is in ready status.
In the program example on the next page, the following device read/write is
executed to the holding register on the slave (Station No. 1) on channel 2.
(Continued on next page)
Figure 9.23 Processing of program example
QJ71MB91
(master)
Device memory
QJ71MB91
(master)
MODBUS
slave device
R
D100
D199
W0000
W001F
100 points
32 points
400500
400531
411000
411099
MODBUS device
R
32 points
100 points
Read
Write
CH2 (RS-422/485)
4
2
5
3
1
6
7
(FG)
(FG)
RS-232
/485
RS-422
CH2
RDB
RDA
SDB
SG
SDA
CH1
QJ71MB91
RUN
RD
NEU.
SD
NEU.
RD
SD
CH1
CH2
ERR.
MODBUS
slave device
(station No.1)
R

Mitsubishi QJ71MB91 Specifications

General

Brand	Mitsubishi
Model	QJ71MB91
Category	Controller
Language	English