Siemens SIMATIC ET 200AL System Manual page 1724

Manufacturer view
You assign the following parameters for an S7-1500 CPU as an I-device: centralized and
distributed I/O, the desired transfer areas, and the number of IO controllers having access to
this I-device (always greater than 1 for a shared device!).
Special consideration: The I-device is configured without a higher-level IO controller. As a
result, only the local I/O addresses of the transfer area are available (= "Address in the I-
device") in order to create the user program for editing the addresses from the transfer area.
The I-device that has been completely configured except for the connection to the higher-
level IO controller is loaded to the S7-1500 CPU.
You export a PROFINET GSD file from the I-device configuration.
Figure 5-26
PROFINET with STEP 7
Function Manual, 05/2021, A5E03444486-AL
Exporting an I-device as a GSD file
Functions
5.3 Shared device
159