Omron CP - PROGRAMMING MANUAL 05-2007 - Page 93

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Using Tasks Section 2-2
A cyclic task that is in Standby status will maintain that status in subsequent
cycles. The task will have to be activated using the TKON(820) instruction in
order to switch from Standby to READY status.
If a TKOF(821) instruction is executed for the task it is in, the task will stop
being executed where the instruction is executed, and the task will shift to
Standby status.
Cyclic Task Numbers
and the Execution
Cycle (Including Extra
Cyclic Tasks)
If task m turns ON task n and m > n, task n will go to READY status the next
cycle.
Example: If task 5 turns ON task 2, task 2 will go to READY status the next
cycle.
If task m turns ON task n and m < n, task n will go to READY status the same
cycle.
Example: If task 2 turns ON task 5, task 5 will go to READY status in the
same cycle.
If task m places task n in Standby status and m > n, will go to Standby status
the next cycle.
Example: If task 5 places task 2 in Standby status, task 2 will go to Standby
status the next cycle.
If task m places task n in Standby status and m < n, task n will go to Standby
status in the same cycle.
Example: If task 2 places task 5 in Standby status, task 5 will go to Standby
status in the same cycle.
Relationship of Tasks
to I/O Memory
There are two different ways to use Index Registers (IR) and Data Registers
(DR): 1) Independently by task or 2) Shared by all task.
With independent registers, IR0 used by cyclic task 1 for example is different
from IR0 used by cyclic task 2. With shared registers, IR0 used by cyclic task
1 for example is the same as IR0 used by cyclic task 2.
The setting that determines if registers are independent or shared is made
from the CX-Programmer.
Cyclic task 1
Cyclic task 2
Cyclic task 1
Cyclic task 2
RUN status RUN status
TKON
(820)
Standby
status
Standby
status
TKOF(821)
Task execution will
stop here and the task
will shift to Standby
status.
Task 2