Siemens SIMATIC S7 System Manual page 422

Communication
8.5 PROFIBUS
In the figure below, the S7-200 SMART CPU is a DP device for an S7-1200 controller:
You can configure two PROFIBUS EMs per S7-200 SMART CPU (ST and SR models only).
The local CPU stores the PROFIBUS EM configuration data, and you set the PROFIBUS
addresses with switches on each module. This allows simple replacement of these
communications modules when necessary.
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System Manual, V2.3, 07/2017, A5E03822230-AF
S7-200 SMART