Interrupt Task Flags And Words - Omron CJ - PROGRAMMING MANUAL 08-2008 Programming Manual

Interrupt Tasks
4-3-3

Interrupt Task Flags and Words

Note If you do not want a specific I/O interrupt task number to be saved and exe-
cuted for a CS-series CPU Unit when it occurs while another interrupt task is
being executed, execute the CLI (CLEAR INTERRUPT) instruction from the
other interrupt task to CLEAR the interrupt number saved internally. Sched-
uled interrupts and external interrupts cannot be cancelled.
Cyclic task
Multiple Interrupts Occurring Simultaneously
Interrupt tasks other than power OFF interrupt tasks will be executed in the
following order of priority whenever multiple interrupts occur simultaneously.
I/O interrupt tasks (CS Series only) > external interrupt tasks (CS Series only)
> scheduled interrupt tasks
Each of the various types of interrupt task will be executed in order starting
from the lowest number if more than one occurs.
Note Only one interrupt will be recorded in memory for each interrupt task and an
interrupt will not be recorded for an interrupt that is already being executed.
Because of the low order of priority of scheduled interrupts and because that
only one interrupt is recorded at a time, it is possible for a scheduled interrupt
to be skipped.
Maximum Interrupt Task Processing Time (A440)
The maximum processing time for an interrupt task is stored in binary data in
0.1-ms units and is cleared at the start of operation.
Interrupt Task with Maximum Processing Time (A441)
The interrupt task number with maximum processing time is stored in binary
data. Here, 8000 to 80FF Hex correspond to task numbers 00 to FF Hex.
A44115 will turn ON when the first interrupt occurs after the start of operation.
The maximum processing time for subsequent interrupt tasks will be stored in
the rightmost two digits in hexadecimal and will be cleared at the start of oper-
ation.
Interrupt Task Error Flag (Nonfatal Error) (A40213)
If Interrupt Task Error Detection is turned ON in the PLC Setup, the Interrupt
Task Error Flag will turn ON if an interrupt task error occurs.
Interrupt task 101 will be ignored while
another interrupt task is being executed.
Interrupt task A
Section 4-3
Interrupt
I/O interrupt task
during
execution
Interrupt task 101 will
not be executed.
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