Omron SYSMAC CS Series Programming Manual page 165

Using Tasks
Task 3
Disabled
ask Flag for task 3
Initial Task Execution Flag
(A20015)
nitial Task Execution Flag
Task Error Flag (A29512)
Cycle
READY
Note Task Flags are used only with cyclic tasks and not with interrupt tasks. With
an interrupt task, A44115 will turn ON if an interrupt task executes after the
start of operation, and the number of the interrupt task that required for maxi-
mum processing time will be stored in two-digit hexadecimal in A44100 to
A44107.
The Initial Task Execution Flag will turn ON when cyclic tasks shift from Dis-
abled to READY status, the tasks obtain the right to execute, and the tasks
are executed the first time. It will turn OFF when the first execution of the tasks
has been completed.
Task n
Disabled
The Initial Task Execution Flag tells whether or not the cyclic tasks are being
executed for the first time. This flag can thus be used to perform initialization
processing within the tasks.
Note Even though a Standby cyclic task is shifted back to READY status through
the TKON(820) instruction, this is not considered an initial execution and the
Initial Task Execution Flag (20015) will not turn ON. The Initial Task Execution
Flag (20015) will also not turn ON if a cyclic task is shifted from Disabled to
RUN status or if it is put in Standby status by another task through the
TKOF(821) instruction before the right to execute actually is obtained.
The Task Error Flag will turn ON if one of the following task errors occurs.
• No cyclic tasks are READY during a cycle.
• The program allocated to a cyclic task does not exist. (This situation will
not occur when using the CX-Programmer or a Programming Console.)
• No program is allocated to an activated interrupt task.
Cycle
READY
Cycle
READY
RUN
Tasks executed in sequential
order starting at the lowest
number.
Initial Task Execution Flag
Initializing
processing
Section 4-2
Cycle
Standby
145