Interrupts Of The Sm 338; Pos Input; Enabling Interrupts; Diagnostic Interrupt - Siemens SM 338 Reference Manual

1.1.6

Interrupts of the SM 338; POS INPUT

Introduction
In this Section, the interrupt behavior of the SM 338; POS-INPUT is described.
The SM 338 can trigger diagnostic interrupts.
The OBs and SFCs mentioned below can be found in the online Help for STEP 7,
where they are described in greater detail.

Enabling interrupts

The interrupts are not preset – in other words, they are inhibited without
appropriate parameter assignment. Assign parameters to the Interrupt Enable in
STEP 7 (refer to Section 1.1.3).

Diagnostic interrupt

If you have enabled diagnostic interrupts, then incoming active error events (initial
occurrence of the error) and departing error events (message after
troubleshooting) are reported by means of interrupts.
The CPU interrupts execution of the user program and processes the diagnostic
interrupt block (OB 82).
In the user program, you can call SFC 51 or SFC 59 in OB 82 to obtain more
detailed diagnostic information from the module.
The diagnostic information is consistent until such time as OB 82 is exited. When
OB 82 is exited, the diagnostic interrupt is acknowledged on the module.
Product Information on the Reference Manual Programmable Logic Controllers S7-300 Module Data Release 3
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