User guide

Configuring an M1 CPU with Concept
870 USE 101 00 V.2.2
277
Changing the Protocol on Modbus Port 2
Overview
If your TSX Momentum M1 CPU is using the Modbus Port 2 provided by the 172
JNN 210 32 Option Adapter, you can specify whether it will use the RS232 or
RS485 protocol. The factory-set default for Modbus Port 2 is RS232.
Note:
If you are using the Modbus Port 2 provided on the 171 CCS 780 00
Processor Adapter, the port is hardwired as a dedicated RS485 protocol. You must
change the default setting on the Port editor screen from RS232 to RS485, or the
port will not function correctly.
Procedure
From the Modbus Port Settings dialog box, perform the steps in the following table
to change the Protocol on Modbus Port 2.

Step Action
1 Click on the down arrow under the Protocol heading.
Result:
A menu appears with the two protocol options.
2 Click on
RS232
or
RS485
.
Result:
The Modbus Port Settings dialog box is updated with the protocol you have
specified.