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Using Tasks Section 4-2
the time can be made into tasks and assigned Standby status to reduce cycle
time.
Note Standby status simply means that a task will be skipped during task execu-
tion. Changing to Standby status will not end the program.
4-2 Using Tasks
4-2-1 TASK ON and TASK OFF
The TASK ON (TKON(820)) and TASK OFF (TKOF(821)) instructions switch a
cyclic task (including extra cyclic tasks) between READY and Standby status
from a program.
Note Extra cyclic tasks are supported only by CS1-H, CJ1-H, CJ1M, or CS1D CPU
Units.
The TASK ON and TASK OFF instructions can be used to change any cyclic
task between READY or Standby status at any time. A cyclic task that is in
READY status will maintain that status in subsequent cycles, and a cyclic task
that is in Standby status will maintain that status in subsequent cycles.
The TASK ON and TASK OFF instructions can be used only with cyclic tasks
and not with interrupt tasks.
Note At least one cyclic task must be in READY status in each cycle. If there is not
cyclic task in READY status, the Task Error Flag (A29512) will turn ON, and
the CPU Unit will stop running.
Conventional program
Executes under
set conditions
Executes under
set conditions
All instructions will
be executed un-
less jumps or other
functions are used.
Task
Reduced cycle time
N: Task No.
N: Task No.
A task will go to READY status when the
execution condition is ON, and the corre-
sponding Task Flag will turn ON.
A task will go to Standby status when
the execution condition is ON, and the
corresponding Task Flag will turn OFF.
Note: Task Flags do not work for extra cyclic tasks.
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