Omron sysmac NX102-9 Series Owner's Manual page 185

• NJ-series CPU Units
• Execution of the tag data link service is given priority over execution of the priority-17 periodic
task. However, execution of the primary periodic task and priority-16 periodic task is given
even higher priority.
• The system services are executed in the unused time between execution of all of the tasks
and tag data link service.
Execution
Primary period
priority
High
Primary
periodic task
Priority-16
periodic task
Tag data link
service
Priority-17
periodic task
System service
Low
Additional Information
If a program needs to access a network variable with an AT specification, set the program in the
primary periodic task so that it matches the refresh timing of the network variable that uses an
AT specification. (This applies to the NX102 CPU Unit, NX1P2 CPU Unit, and NJ-series CPU
Unit.)
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506)
(1) Execution timing of the program
(2) Refresh timing of network variables (tags) with the primary periodic task set as the refreshing task*
(3) Refresh timing of network variables (tags) that do not have the primary periodic task set as the refreshing task
(1) (2) (1) (2)
IO UPG MC IO UPG MC
Task period
IO UPG
(2)
(3)
Tag data is read
UPG
from the tag set.
*: Refreshed during system common processing 2 in the task processing.
7 Tag Data Link Functions
(1) (2) (1) (2)
IO UPG MC IO UPG MC
Task period
Pausing
(1) (2)
IO UPG MC
IO UPG
(3)
.....
The system service is executed
during free time between task
execution.
7-17
7