Tasks; Overview Of Tasks - Omron CJ2 CPU - REV 10-2010 User Manual

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Tasks

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Overview of Tasks

Concept of Tasks
Tasks are used to divide a program into large units and specify the order in which to execute each unit
or programming. Instructions in any one task can be used to enable or disable the execution of other

tasks.

This means that several program components can be assembled as different tasks, and that only spe-
cific tasks can then be executed as needed for the current product model or process being performed.
This enables switching between different tasks for different processes. Therefore performance (cycle
time) is greatly improved because only required programs will be executed as needed.
Program with no tasks
One continuous
subprogram
I/O refreshing
A program without tasks is like reading an entire scroll form the beginning, while a program with tasks is
like reading cards individually. Each card can enable or disable other cards. Reading disabled cards will
be skipped.
Scroll-type program:
Program with no tasks
The entire program is read.
CJ2 CPU Unit Software User's Manual
Program divided into tasks
Task 1
Allocation
Task 2
Task 3
I/O refreshing
Card-type Program:
Program divided into tasks
Only the required cards are read.
5 Understanding Programming
It is possible
to pause any
task.
Task 1
Task 2
Task 3
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