Siemens SIMATIC IM151-1 STANDARD

Interrupt, error, and system messages
4.4 Diagnostics with STEP 7
Interface module IM151-1 STANDARD (6ES7151-1AA06-0AB0)
52 Manual, 07/2015, A5E01075950-AD
Diagnostic interrupt from the modules, byte x+12 to byte x+15
Figure 4-8 Structure of byte x+12 to byte x+15 for diagnostic frame