Siemens SIMATIC S7-1200 CP 1243-8 IRC Operating Instructions Manual page 170

Program blocks
5.2 Changing the IP address during runtime
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
The address parameters can only be configured with temporary validity in the CP. In the
respective "IF_CONF_..." SDT, the "Mode" = 2 parameter must be set.
Note
No feedback from the CP
"T_CONFIG" does not support feedback from the CP to the CPU. Errors in the block call
or in setting the address parameter are not reported. The block outputs "BUSY" or
"DONE" regardless of whether the address parameter was set.
● 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.
170
Operating Instructions, 02/2018, C79000-G8976-C385-03
CP 1243-8 IRC