Delta Electronics DVP15MC11T Operation Manual page 66

○
3 The controller will execute the system processing if there is no other task after the execution of
E A
the freewheeling task is completed.
○
4 The execution of the freewheeling task continues since the high-priority cyclic task request has
A E A
not arrived.
○
5 The cyclic task interrupts the freewheeling task execution and the controller executes the cyclic
A E A
task because of the arrival of the high-priority cyclic task request during the execution of the
freewheeling task.
○
6 The controller continues to execute the part of the low-priority freewheeling task, which has not
A E A
been executed yet when the execution of the cyclic task is completed.
○
7 When the execution of the freewheeling task is completed, the controller executes the system
A E A
processing due to no other task request.
○
8 When the system processing is completed, the execution of the freewheeling task continues due
A E A
to no high-priority cyclic task request.

When three tasks are executed in mixture (Event task, Cyclic task and Freewheeling task)
P riorit y
Hig h
Task trigg ered by
e ve nt
( )
P rio rit y 1
Task execu tion time
User
F re ewh eelin g task
IO
( ) program
Priority 2
1
Task execution Task execution
condition met finished
Cyclic task
Pause IO
(Priority 3)
Task execution
condition met
Syst em
p ro cessing
Low
○
1 When the conditions for execution of the freewheeling task and cyclic task are both met, the
A E A
freewheeling task is executed first because the priority of the freewheeling task is higher.
○
2 The cyclic task execution starts when the freewheeling task execution is completed.
A E A
○
3 When the cyclic task execution is completed, the controller executes the system processing due
A E A
to no other task request.
○
4 The freewheeling task is executed when the system processing is completed.
A E A
○
5 When the freewheeling task execution is completed, the controller executes the system
A E A
processing due to no other task request.
○
6 The freewheeling task is executed when the system processing is completed.
A E A
○
7 The freewheeling task execution continues because the freewheeling task has a higher priority
A E A
than the cyclic task although the execution condition for the cyclic task is met. And the cyclic task
waits to execute.
The event task has not be en t rig gered
Task execut io n time
User
IO IO
program
Task
2 4 5
Task execution execution
Task execution
condition met finished
condition met
Time int erval between tasks
User
program
3
Task execution
Task execution
finished
System Syste m
processing proce ssin g
Chapter 7 Introduction of Axis Parameters
Task exe cut ion t ime
User
IO
program
8 9
Task execution
Task execution
finished
condition met
Task execution time
User User
Pau se
program program
6
Task execution
finished
Time interval between tasks
P ause
7
condition met
Tas k exec uti on tim e
User
I O
program
1 0 1 2
Task execution
condition met
Time interval between tasks
User
IO
program
1 1
Task execution
finished
System
processing
7-5
7_