Interrupt Handling - Siemens SIMATIC FM 351 Installation Manual

Programming the FM 351
6.1.3
Types of Interrupt
Requirements
6 Interrupt
Information
Reading
Diagnostic Data
Read Diagnostic
Data: Preparation
in OB 82
6-8

Interrupt Handling

The FM 351 can release diagnostic interrupts in the CPU.
You must have programmed the diagnostic interrupt OB for handling diag-
nostic interrupts.
Note
If you have not programmed the interrupt OB (OB 82), the CPU goes to
STOP in the event of an interrupt.
The operating system makes available 4 bytes of interrupt information as
group information which you must evaluate for error analysis. You can read
further data from the FM 351. To do this, use the FC DIAG_INF which you
call in the cyclic program.
The following notes about OB 82 and OB 1 show how you read diagnostic
data from the FM 351 in the event of an interrupt. You call the FC
DIAG_INF in the cyclic program.
Note
If an FC which writes or reads data to the FM 351 is already started in the
OB 1 cycle, no further FC (for example, FC DIAG_INF) may be called in
the interrupt OB.
OB 82 must be programmed for diagnostic interrupts. The following assign-
ment would be possible as a minimum program.
STL
SET;
S DIAGNOSTIC INTERRUPT;
If a number of modules capable of diagnosis are mounted in your system, you
must also incorporate evaluation for identifying the source of the interrupt.
Explanation
RLO is set to "1"
Enable calling of FC DIAG_INF
FM 351 Positioning Function Module
EWA 4NEB 720 6001-02