Specifications Of Tasks - Omron NJ-series User Manual

5 Designing Tasks
Guidelines for Separating Tasks
All programs must be assigned to one of the tasks. Use the guidelines in the following table to deter-
mine which tasks to assign your programs to based on the requirements of the programs.
Task
Primary periodic task
Priority-16 periodic task
Priority-17 or priority-18 periodic
task
Event Task
5-2-2

Specifications of Tasks

The specifications of tasks are given in the following table.
Item
Type of task
Numbers of tasks
Number of programs per
task
Task period of the primary
periodic task
Task periods of periodic
tasks
*1 There can be no more than one task with each of the following execution priorities: 16, 17, and 18.
*2 There can be up to 32 tasks with each of the following priorities as long as there are no more than a total of 32
tasks with these priorities: 8 and 48.
*3 With the NJ301-, you can use this setting with unit version 1.03 or later.
 Valid Task Periods for Periodic Tasks
Task period of the primary periodic task
500 µs*
1 ms
2 ms
4 ms
* With the NJ301-, you can use this setting with unit version 1.03 or later.
5-6
Programs that are suitable for this task
• Programs that require I/O refreshing at an exact execution period.
• Programs that require the highest execution priority.
• Programs that include motion control processing.
• Programs that require I/O refreshing.
• Programs with a relatively low execution priority that must be executed
periodically.
• Programs that contain motion controls with a relatively low execution pri-
ority.
• Programs with a relatively low execution priority that must be executed
periodically.
• Programs that are executed only when specified conditions are met.
Specification
• Primary periodic task
• Periodic task (priority 16, 17, or 18)
• Event task (priority 8 or 48)
• Primary periodic task: 1
• Periodic tasks: 0 to 3 tasks
*2
• Event tasks: 0 to 32 tasks
128 max.
500 s
*3
, 1 ms, 2 ms, or 4 ms
Set the task period of each periodic task to an integer multiple of the task period of
the primary periodic task. Refer to the table of valid task periods for periodic tasks
that is given below.
Task periods that you can set for periodic tasks
1 ms, 2 ms, 3 ms, 4 ms, 5 ms, 8 ms, 10 ms, 15 ms, 20 ms, 25 ms,
30 ms, 40 ms, 50 ms, 60 ms, 75 ms, or 100 ms
1 ms, 2 ms, 3 ms, 4 ms, 5 ms, 8 ms, 10 ms, 15 ms, 20 ms, 25 ms,
30 ms, 40 ms, 50 ms, 60 ms, 75 ms, or 100 ms
2 ms, 4 ms, 8 ms, 10 ms, 20 ms, 30 ms, 40 ms, 50 ms, 60 ms, or
100 ms
4 ms, 8 ms, 20 ms, 40 ms, 60 ms, or 100 ms
*1
NJ-series CPU Unit Software User's Manual (W501)