Omron NY532-5400 Reference Manual page 1440

2 Instruction Descriptions
If an event task is started that has an execution priority that is higher than the execution priority of the
task in which this instruction was executed, the execution of the task in which this instruction was exe-
cuted is paused and the event task is executed. For example, assume that the execution priority of peri-
odic task T2 is lower than the execution priority of event task T1. If the ActEventTask instruction is
executed for T1 in T2, the execution of T2 is paused to execute T1.
Execution priority
High Event
task T1
Periodic
Low
task T2
The following figure shows a programming example. When the value of variable A is TRUE, event task
'Te' is executed.
LD
A
'Te'
Assume that the program with these instructions is assigned to periodic task T1 and that the execution
priority of Te is lower than that of T1. If this instruction is executed in T1, the execution of T1 is com-
pleted before Te is executed.
Execution priority
High
Periodic
task T1
Event
Low
task Te
Related System-defined Variables
Name
*1
_**_Active
*1 The asterisks (**) are replaced with the task name.
*2 Refer to the NJ/NX-series CPU Unit Software User's Manual (Cat. No. W501) or NY-series Industrial Panel PC / Industrial
Box PC Software User's Manual (Cat. No. W558) for details.
2-1388
T1 is executed immediately after execution
of the ActEventTask instruction.
Task period
ActEventTask('T1')
ST
@ActEventTask
EN ENO
TaskName
Task period Task period
ActEventTask('Te')
Te is executed after the execution
of T1 is completed.
Meaning
Task Active Flag
Execution of task processing
Pausing of task processing
Task period
Time
IF A=TRUE THEN
ActEventTask('Te');
END_IF;
Execution of task processing
Time
Data
type
BOOL This variable indicates the execution status of the
*2
task.
TRUE: Execution processing is in progress.
FALSE: Stopped.
NY-series Instructions Reference Manual (W560)
Description