Mitsubishi QJ71MB91 User Manual

6
PRE-OPERATIONAL PROCEDURES AND SETTINGS
6.6 Intelligent Function Module Switch Setting
6 - 22
1
OVERVIEW
2
SYSTEM CONFIGURATION
3
SPECIFICATIONS
4
MODBUS(R) STANDARD FUNCTIONS
5
FUNCTION
6
PRE-OPERATIONAL PROCEDURES AND SETTINGS
7
PARAMETER SETTING
8
UTILITY PACKAGE (GX Configurator-MB)
(b) Communication speed/transmission setting (Switch 2: CH1 side, Switch 4: CH2
side)
Set a speed of communication with the target device, and transmission details.
1) Transmission setting
* 1 Set the MODBUS device assignment parameters before sending request messages to the
QJ71MB91.
If a request message is sent before the setting, the QJ71MB91 will send a response message
(error completion). (The slave function does not operate.)
* 2 Set it to OFF (8 bits) in RTU mode.
Figure 6.21 Structure of communication speed and transmission
settings
Table6.8 Transmission setting
Bit Item OFF (0) ON (1) Description
b0
MODBUS
device
assignment
parameter
starting
method
Switch 2
Start with the
default
parameters
Start with the
user-set
parameters
*1
The MODBUS device assignment parameter starting method
must be set only for Switch 2 regardless of the channel used.
When "Start with the default parameters" is set, the module is
started with the parameters assigned by default.( Section
7.3.1 (3))
When "Start with the user-set parameters" is set, the module is
started with the MODBUS device assignment parameters set on
the sequence program or GX Configurator-MB.( Section
7.3.1 (2))
When setting parameters using the GX Configurator-MB, turn the
MODBUS device assignment parameter start method ON.
Switch 4 Fixed to OFF(0) -
b1
Data bit
*2
8 7 Set data bits.
b2 Parity bit presence Present Not present
Specify whether parity bit is present or not.
In the case of "Present", vertical parity check is performed.
b3 Even/odd parity Even Odd
Set even or odd parity.
This setting is valid only when "Parity bit presence" is set to
"Present".
b4 Stop bit 1 2 Set the stop bit.
b5 Frame mode RTU mode ASCII mode
Set the frame mode.( Section 4.2.1)
b6 Online change Disable Enable
Set whether to enable or disable data writing to the RUN-status
programmable controller CPU by a request message from the
master.
If this is set to "Disable", when a message requesting the device
write is received from the master, the QJ71MB91 returns an error
response.
This setting is valid only when the slave function is set for the
channel.
b7 Not used Fixed to OFF(0) -
b0b1b2b3b4b5b6b7b8b9
Communication speed setting
Transmission setting
b15 b14 b13 b12 b11 b10

Mitsubishi QJ71MB91 Specifications

General

Brand	Mitsubishi
Model	QJ71MB91
Category	Controller
Language	English