Interrupts Of The Sm 322; Do 8 X Vdc 24/0.5 A - Siemens SIMATIC S7-300 Reference Manual

Digital Modules
3.23.3

Interrupts of the SM 322; DO 8 x VDC 24/0.5 A

Introduction
The SM 322; DO 8 x 24 VDC/0.5 A 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 3.23.1).
Diagnostic interrupt
If you have enabled diagnostic interrupts, then active error events (initial
occurrence of the error) and departing error events (message after
troubleshooting) are reported by means of an interrupt.
The CPU interrupts the 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.
3-80
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03