Siemens SIMATIC NET TeleControl S7-1200 CP 1243-1 Operating Instructions Manual page 38

Configuration
4.3 Address and authentication data
Note
Changing the IP parameters with a dynamic IP address
Note the effects of program-controlled changes to the IP parameters if the CP obtains a
dynamic IP address from the Internet service provider: In this case, the CP can no longer be
reached by communications partners.
Requirements - firmware version
Requirements for program-controlled changing of the IP parameters are as follows:
● CP firmware ≥ V2.1.7x
and
● CPU firmware ≥ V4.2
Requirements - program blocks / STEP 7 versions
Program-controlled changing of the IP parameters is supported by program blocks. The
program blocks access address data stored in a suitable system data type (SDT).
Apart from the address parameters of the CP, with T_CONFIG the address parameters of
DNS servers (IF_CONF_DNS) and NTP servers (IF_CONF_NTP) can also be changed
program controlled.
Depending on the STEP 7 version, the following program blocks and system data types can
be used:
● STEP 7 Basic ≥ V14
T_CONFIG
Along with:
– IF_CONF_V4
– IF_CONF_NTP
– IF_CONF_V6
– IF_CONF_DNS
● STEP 7 Basic ≤ V14
TC_CONFIG
Along with:
– IF_CONF_V4
You will find detailed information on programming the blocks in the STEP 7 information
system.
Requirements - CP programming
To be able to change the IP parameters program controlled the option "IP address is set
directly at the device" must be enabled in the configuration of the IP address of the Ethernet
interface of the CP.
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Operating Instructions, 12/2016, C79000-G8976-C365-02
CP 1243-1