Siemens SIMATIC S7-400H System Manual page 94

PROFIBUS DP
7.1 CPU 41x–H as PROFIBUS DP master
Evaluation in the user program
The table below shows you how to evaluate RUN-STOP changes of the DP slave on the DP
master. Also refer to previous table.
On the DP master
Example of diagnostics addresses:

Master diagnostics address=1023
Slave diagnostics address in master
system=1022
The CPU calls OB 82 with the following information, for example:
OB 82_MDL_ADDR:=1022

OB82_EV_CLASS:=B#16#39

As incoming event
OB82_MDL_DEFECT:=module error

The CPU diagnostic buffer also contains this information
Your user program should also be set up to read the diagnostic
data of the DP slave using SFC 13 "DPNRM_DG".
Use SFB 54 in the DPV1 environment. This outputs the full interrupt
information.
94
On the DP slave (CPU 41x)
Example of diagnostics addresses:

Slave diagnostics address=422
Master diagnostics address=irrelevant
CPU: RUN → STOP
CPU generates a DP slave diagnostics frame.
System Manual, 03/2012, A5E00267695-11
S7-400H