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Siemens AG
Entry type: FAQ Entry ID: 51577287, Entry date: 08/15/2011

How can you detect a change in the S7 user program in STEP 7 V5.5?

  • Entry
  • Associated product(s)

The S7 program which is available in this FAQ as a download offers the opportunity to detect changes in the program code and in the hardware configuration. The appropriate checksums from the system status list are determined and verified here.

If a change is detected, a user-definable entry is created in the diagnostic buffer of the CPU.

PROG_CHECK_en.pdf ( 355 KB )

PROG_CHECK.zip ( 253 KB )

Creation environment
The pictures and downloads in this FAQ were created with SIMATIC STEP 7 V5.5.

Program protection, SFC51

Security information
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