Siemens SIMATIC S7-1500 Manual page 29

The following figure shows the assignment of the address space with submodules 3 and 4.
Figure 4-5
Reference
You can find information on the Shared Input/Output (MSI/MSO) function in the section
Module-Internal Shared Input/Output (MSI/MSO) of the PROFINET with STEP 7 V13
(https://support.industry.siemens.com/cs/ww/en/view/49948856) function manual.
Analog Input Module AI 8xU/I HS (6ES7531-7NF10-0AB0)
Manual, 12/2016, A5E03484886-AE
Address space for configuration as 1 x 8-channel AI 8xU/I HS MSI with value status
Parameters/address space
4.4 Address space
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