WI-GTWY-9-xxx Wireless Gateway V1.18
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Supported Exception Codes:
Exception
Code
Name
Description
01
Illegal function
The module does not support the function code in the query
02
Illegal data address The data address received in the query is outside the
initialized memory area
03
Illegal data value
The data in the request is illegal
06
Busy
Unable to process message
4.7.2
MODBUS Master
If you use the WI-GTWY-9-xxx as a Modbus Master, then the host device/s will be Modbus
Slave device/s. If the RS485 port is used, then multiple Modbus Slave devices can be connected
to the WI-GTWY-9-xxx.
The WI-GTWY-9-xxx Modbus Master will generate Modbus read and write commands to the
Modbus Slave devices.
First read the above section on Modbus Slave operation, for an understanding of how the WI-
GTWY-9-xxx handles Modbus registers, and the types of Modbus commands the WI-GTWY-9-
xxx Master can generate.
The Modbus Master commands are configured in the “Serial Mapping” screen. The serial port is
configured in the same way as described in the above section on Modbus Slave.
To enter a Modbus command, select “New Serial Mapping”. The following example is a digital
write command which writes WI-GTWY-9-xxx I/O registers 20 – 25 (6 registers) to Modbus
outputs 00012 – 00017, at Modbus Slave address 1.
The entry under “I/O Register” is the first I/O register in the WI-GTWY-9-xxx to be transferred
- the “I/O count” is the number of registers to be transferred. If the selected Modbus slave does
