Interrupts Of Analog Modules - Siemens SIMATIC Manual

Principles of analog modules

5.9 Interrupts of analog modules

5.9 Interrupts of analog modules
Introduction
This section describes the interrupt response of analog modules. Always distinguish
between the following interrupts:
● Diagnostic interrupt
● Hardware interrupt
Note that certain analog modules do not support interrupts, or are only partially capable of
"handling" the interrupts described below. For information on modules which support
interrupt functionality, refer to their technical data.
STEP 7
Description of the
For detailed information on the OBs and SFCs mentioned below, refer to the
Help.
Enabling interrupts
There are no default interrupt settings, that is, interrupts are disabled if not set accordingly.
Program the interrupt enable parameter in
Diagnostic interrupt
Incoming error events (initial occurrence) and outgoing error events (error is cleared) are
reported by means of diagnostic interrupt, if this interrupt is enabled.
The CPU interrupts user program execution in order to process diagnostic interrupt OB82.
You can call SFC51 or 59 in OB82 in the user program to view details of diagnostics data
output by the module.
Diagnostics data remain consistent until the program exits OB82. The program
acknowledges the diagnostic interrupt at the module when it exits OB82.
Hardware interrupt with "high or low limit exceeded" trigger
Define a working range by setting a high and low limit. If the process signal (for example, the
temperature) overshoots this working range, the module triggers a hardware interrupt,
provided the interrupt is enabled.
The CPU interrupts user program execution in order to execute hardware interrupt OB40.
In the user program of OB 40, you can define the reaction of the automation system to the
violation of limits.
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Manual, 06/2017, A5E00105505-AJ
STEP 7
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S7-300 Module data