Select and add the desired serial interface option board type for the required option board slot.

The option board may require additional channel configuration, depending on the application.

The following example shows how to add a TA5142-RS485I isolated interface and select the required protocol.

The required protocol must also to be added according to the application, e.g. Modbus RTU client.

The parameter for the serial interface can also be adapted, such as data transmission rate, data bits, stop bits or parity.