Dis_Airt And En_Airt (Delay/Enable Execution Of Higher Priority Interrupts And Asynchronous Error Events) Instructions - Siemens S7-1200 System Manual

Extended instructions
8.5 Diagnostics (PROFINET or PROFIBUS)
8.4.5 DIS_AIRT and EN_AIRT (Delay/enable execution of higher priority interrupts
and asynchronous error events) instructions
Use the DIS_AIRT and EN_AIRT instructions to disable and enable alarm interrupt
processing.
Table 8- 112 DIS_AIRT and EN_AIRT instructions
LAD / FBD SCL
DIS_AIRT();
EN_AIRT();
Table 8- 113 Data types for the parameters
Parameter and type
RET_VAL OUT
The DIS_AIRT executions are counted by the operating system. Each of these remains in
effect until it is cancelled again specifically by an EN_AIRT instruction, or until the current OB
has been completely processed. For example: if you disabled interrupts five times with five
DIS_AIRT executions, you must cancel these with five EN_AIRT executions before interrupts
become enabled again.
After the interrupt events are enabled again, the interrupts that occurred while DIS_AIRT was
in effect are processed, or the interrupts are processed as soon as the current OB has been
executed.
Parameter RET_VAL indicates the number of times that interrupt processing was disabled,
which is the number of queued DIS_AIRT executions. Interrupt processing is only enabled
again when parameter RET_VAL = 0.
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Description
DIS_AIRT delays the processing of new interrupt events. You can execute
DIS_AIRT more than once in an OB.
EN_AIRT enables the processing of interrupt events that you previously disabled
with the DIS_AIRT instruction. Each DIS_AIRT execution must be cancelled by an
EN_AIRT execution.
The EN_AIRT executions must occur within the same OB, or any FC or FB called
from the same OB, before interrupts are enabled again for this OB.
Data type Description
Int Number of delays = number of DIS_AIRT executions in the queue.
S7-1200 Programmable controller
System Manual, 03/2014, A5E02486680-AG