Omron Sysmac NJ-series User Manual

7-15
7 Tag Data Link Functions
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User’s Manual (W506)
7-1 Introduction to Tag Data Links
7
7-1-7 Concurrency of Tag Data Link Data
 Synchronizing the Update Timing of Network Variables (Tags) with the User
Program Execution Period
To have the values of network variables (tags) updated to the latest tag data values each time the
user program that accesses those network variables is executed, set the refreshing task for the net-
work variables (tags) to the same type of the task as for the user program that accesses the network
variables (tags).
The difference between the operation of tags with a refreshing task that is the same as the user pro-
gram and tags without a refreshing task is described below.
• Tag (network variable) with a refreshing task
The tag is refreshed each time the program with the task that is set as the refreshing task is exe-
cuted.
• Tag (network variable) without a refreshing task
The tag is refreshed by the system service.
Refreshing is not synchronized to the execution timing of the program.
The diagram shows the refreshing timing of network variables for each CPU Unit.
• NX701 CPU Units
• The tag data link service is executed without being affected by the tasks and system services.
• The system services are executed at the required time without being affected by the tasks
and tag data link service.
UPG
IO
IO UPG MC
UPG
IO
IO
UPG MC
IO
UPG MC
IO
UPG MC
IO
UPG MC
UP
G
Execution
priority
Primary period
High
Low
Primary
periodic task
Priority-16
periodic task
Priority-17
periodic task
(1) (2) (1) (2)
(2)
(1) (2) (1) (2) (1) (2)
*: Refreshed during system common processing 2 in the task processing.
(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
System service
(3)
(3)
Task
p
eriod
Tag data is read
from the tag set.
Task
p
eriod
Pausing
Tag data link
service
System services are executed any time when there is no
influence from tasks and tag data links.

Omron Sysmac NJ-series Specifications

General

Brand	Omron
Model	Sysmac NJ-series
Category	Computer Hardware
Language	English