Triggering Diagnostics Interrupts - Siemens SIMATIC S7-300 FM 350-1 Manual

10.2

Triggering diagnostics interrupts

Definition of a diagnostics interrupt
You can determine reactions to internal or external errors in the user program, by
programming a diagnostics interrupt which interrupts cyclic program execution on the CPU,
and triggers a call of diagnostics interrupt OB 82.
Events which can trigger a diagnostics interrupt
The list shows which events can trigger a diagnostics interrupt:
● Short-circuit or overload at the external auxiliary voltage 1L+/1M
● Error at the 5.2 V DC encoder supply
● No module configuration
● Faulty module parameters
● Watchdog timeout
● RAM defective
● Hardware interrupt lost
● Signal A error (wire break, short-circuit, cable missing)
● Signal B error (wire break, short-circuit, cable missing)
● Signal N error (wire break, short-circuit, cable missing)
Enabling diagnostics interrupts
You disable or enable interrupts at the module, and define whether it should generate
diagnostics and/or a hardware interrupts using the programming interfaces.
Reactions to a diagnostics interrupt
Actions initiated when an event triggers a diagnostics interrupt:
● The diagnostics information will be written to the diagnostics data records DS0 and DS1.
● The group error LED is lit.
● Call of the diagnostics interrupt OB 82.
● The diagnostics data record DS0 will be written to the start information of the diagnostics
● The count continues unchanged.
If no OB 82 is programmed, the CPU goes into STOP.
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
The group error LED does dark when the error is eliminated.
interrupt OB.
Errors and diagnostics
10.2 Triggering diagnostics interrupts
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