Weidmuller WI-I/O-9-U2: Wireless Mesh I/O & Gateway User Manual V1.2.2 - Manual (Page 76)

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slaves over the radio network will greatly increase radio communications and is
not recommended in busy systems.
Modbus RTU
Master Example
The Modbus RTU mapping is very similar to the Modbus TCP mapping except the
destination is a serial interface instead of an Ethernet address and port.
The first mapping shows a read mapping from a serial device connected on the RS485
port with a Device ID of 5.
It’s reading 1 I/O point starting at remote address 30001 and
writing the value into the local address 40501.
It’s configured with a response timeout of
1000mSec and local register 508 will indicate a failure to communicate with this device.
The Second mapping shows a read mapping from a serial device connected on the
RS485 port with a Device ID of 5. It’s reading 16 I/O points starting at remote address
10001 and writing the value into the local address 501. It’s configured with a response
timeout of 1000mSec and local register 507 will indicate a failure to communicate with
this device.
The last mapping is a Write mapping which will write the local Battery Voltage (Reg
30007) to register 40001 on a serial device connected on the RS232 with a device ID of
6. Again the response timeout is 1000mSec and it has a communications fail register of
506.
Note: The configuration software will indicate if the serial port ‘Operating Mode’ is
not set or set to the wrong mode.
Clicking on the RS232 or RS485 Modbus Parameter tabs will allow you changes
modes.
Figure 58 - Modbus RTU Example
Figure 59 - Operating Mode Error