Siemens SIMATIC S7-1200

Communication processor and Modbus TCP
13.3 Point-to-point (PtP) communication
S7-1200 Programmable controller
System Manual, V4.2, 09/2016, A5E02486680-AK
1137
13.3.7.1
Configuring the communication module
You can configure the CM 1241 from the Device configuration in STEP 7 or with user
program instructions. This example uses the Device configuration method.
● Port configuration: Click the communication port of the CM module from the Device
configuration, and configure the port as shown:
Note
The configuration settings for "Operating mode" and "Receive line initial state" are only
applicable for the CM
1241 (RS422/RS485) module. The other CM 1241 modules do not
have these port
configuration settings. Refer to Configuring the RS422 and RS485
(Page
1140).
● Transmit message configuration: Accept the default for transmit message configuration.
No break is to be sent at message start.