Siemens SIMATIC S7-1500 Manual page 21

The figure below shows the assignment of the address space for submodules 3 and 4 and
the value status.
Figure 4-4
Reference
You will find information on the module-internal shared input/shared output (MSI/MSO)
function in the function manual PROFINET with STEP 7 V13
(http://support.automation.siemens.com/WW/view/en/49948856) in the section Module-
internal shared input/shared output (MSI/MSO).
Digital output module DQ 16x230VAC/2A ST Relay (6ES7522-5HH00-0AB0)
Manual, 07/2017, A5E34934019-AC
Address space for configuration as 1 x 16-channel DQ 16x230VAC/2A ST MSO with
value status
Parameters/address space
4.3 Address space
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