Station number setting
In the MODBUS network, a maximum of 31 MODBUS
RTU equipment can be connected to one GOT.
Assign a non-overlapped station number ranging from 1 to
247 arbitrarily to each MODBUS
In the system configuration, the MODBUS
equipment with the station number set with the host
address must be included.
The station number can be set without regard to the cable
connection order. There is no problem even if station
numbers are not consecutive.
Examples of station number setting
(1) Direct specification
When setting the device, specify the station number of
/RTU equipment of which data is to be
1 to 247
(2) Indirect specification
When setting the device, indirectly specify the station
number of the MODBUS
data is to be changed using the 16-bit GOT internal
data register (GD10 to GD16).
When specifying the station No. from 248 to 254 on GT
Designer3, the value of GD10 to GD16 compatible to
the station No. specification will be the station No. of
0 to 255:
0 : All station specification (broadcast)
255 : Host station access
For the setting other than the above, an
error (dedicated device is out of range) will
(3) All station specification (broadcast)
Target station differs depending on write-in operation or
• For write-in operation, all station will be a target.
• For read-out operation, only the host station will be a
/RTU equipment of which
4. MODBUS(R)/RTU CONNECTION
4.5 MODBUS(R)/RTU Equipment Side Setting
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