6.2.3
How to read the CPU diagnostic buffer
Saving diagnostic data
You can make it easier for service engineers to perform initial diagnostics on a faulty CPU by
saving and having ready the contents of the diagnostic buffer as service data (as of firmware
version V4.0) or in the following formats:
● HEX format
● TXT format
Requirement
The CPU is in STOP mode.
Procedure
1. Select the faulty CPU in the SIMATIC Manager.
2. As of firmware version V4.0:
Select the menu command CPU > Save service data.
Specify the storage location and name. Save the files.
3. Select the menu command PLC > Diagnostics/Settings > Module Information.
The "Module Information - Online" dialog box opens.
4. Select the "Stacks" tab and read out the following system memory:
– Block stack (B stack)
– Interrupt stack (I stack)
5. Provide these data to the service engineers.
6.2.4
CPU fault - preparing diagnostics
Introduction
The following information is important for analyzing a CPU fault:
● Information on the affected CPU
● Information or actions in the event of a fault
Failure - What next?
6.2 Preparing for expert support
Service support and diagnostics (V8.0)
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Service Manual, 03/2012, A5E02779775-02