Siemens SIMATIC S7-1200 CP 1243-8 IRC Operating Instructions Manual page 219

● TS Module Modem
Connection to an analog dial-up network
● Third-party modem
Select the "3rd party modem" entry in the following cases:
– Connection to a dedicated line network
– Connection to a dial-up network
The TS module RS-232 cannot be configured in STEP 7 V5.
AT strings for TS modules
If the CP is connected to a dial-up network via a TS module, the suitable AT string must be
configured in the properties dialog of the network node in STEP 7 V5 for the network node of
the proxy.
Figure D-4
CP 1243-8 IRC
Operating Instructions, 02/2018, C79000-G8976-C385-03
For the connection to a dedicated line network via a dedicated line or analog wireless
modem, a TS module RS-232 is connected to the CP.
For the connection to a dial-up network via a third-party modem, a TS module RS232
is connected to the CP.
Properties dialog of a dial-up network node, "AT initialization" tab
STEP 7 V5 configuration of the proxy
D.2 Special features of the PROXY CP1243-8 IRC
219