Omron Sysmac NX1P2-10 1 Series, User Manual

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Additional Information
A refreshing task maintains concurrency of the value of a global variable from all tasks that ac-
cess that global variable. This is achieved by specifying a single task that can write to that glob-
al variable and not allowing any other task to write to that global variable.
For details on refreshing tasks, refer to the
NJ/NX-series CPU Unit Software User's Manual
(Cat. No. W501) .
Maintaining Concurrency in the Tag Data in a Tag Set
To maintain concurrency in the values of multiple tags in a tag set, the tags (variables with a Network
Publish attribute) must satisfy the following four conditions.
a. The tags must be assigned to the same tag set (connection).
b. A refreshing task must be set for network variables assigned to the tags, and the refreshing task
must be the same for all the tags in the tag set.
*1
c. For NX102, NX1P2, and NJ-series CPU Units, a tag with an AT specification must not be included
in the tag set.
d. The variable access time set for each task must be set to a higher value than is required to transfer
the tag data.
Refer to
15-3-3 Relationship between Task Periods and Packet Intervals (RPIs) on page 15-25 for
details on the variable access time and data transfer.
*1. If you set a refreshing task for network variables, you must set a variable access time to allocate enough time
to access the network variables from outside of the Controller.
• Setting Refreshing Tasks for Tags (Network Variables)
Concurrency of the tags in the tag set is maintained.
NJ/NX-series Controller NJ/NX-series Controller
Connection
Tag data links updated.
Refreshing task Refreshing task
EtherNet/IP
10
10
10
Value of variable
100 " 10
100 " 10
100 " 10
Value of variable
Variable c
Variable b
Variable a
Variable c
Variable b
Variable a
Tag set
Variable f
Variable e
Variable d
Tag set
The values of the
tags in the tag set
are refreshed at
the same time.
Additional Information
For NX102, NX1P2, and NJ-series CPU Units, you do not need to set a refreshing task for vari-
ables (tags) with AT specifications since they are updated in the primary periodic task.
• Not Setting Refreshing Tasks for Tags (Network Variables)
Concurrency of the tags in the tag set is not maintained.
7 Tag Data Link Functions
7-13
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User’s Manual (W506)
7-1 Introduction to T
ag Data Links
7
7-1-7
Concurrency of T
ag Data Link Data