Concurrency Of Tag Data Link Data - Omron CJ1W-EIP21 Operation Manuals

7 Tag Data Link Functions
When you use multiple connections to communicate with one specific node, the information in the Con-
troller status is stored in the following variables if the Controller status is specified in the input tags and
the output tags for all connections.
Controller status
Target Node PLC Operat-
ing Flags
Additional Information
Even if you specify including the Controller status in the output (produce) tags, you do not neces-
sarily need to include it in the input (consume) tags. If you do not include the Controller status in
an input (consume) tag, the contents of the Controller status is not updated in the Target Node
PLC Operating Flags and Target Node PLC Error Flags variables, but it is sent in the input (con-
sume) tag. Therefore, you can use the Controller status data that was received in the input (con-
sume) tag as receive data.
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Concurrency of Tag Data Link Data

To maintain the concurrency of data in a tag data link, you must set a refreshing task for each network
variable that is assigned to a tag.
• Maintain concurrency in the tag data in a tag set.
• The timing of updating network variables that are assigned to tags is synchronized with the execution
period of the program that accesses the network variables.
Additional Information
A refreshing task maintains concurrency of the value of a global variable from all tasks that
access that global variable. This is achieved by specifying a single task that can write to that glo-
bal variable and not allowing any other task to write to that global variable. For details on refresh-
ing tasks, refer to the NJ-series CPU Unit Software User's Manual (Cat. No. W501).
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Variable name
*_TargetPLCMdSta (Tar-
get Node PLC Operating
Flags)
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)
Description of operation
This variable shows the operation information of the Controller at
the target node.
When the EtherNet/IP Unit Is the Originator of the Connection
The array element that corresponds to the target ID at the target
is TRUE when all information for all connections of the relevant
target node is shows operating status. You can change the target
ID of the IP address from the Network Configurator. This status
information is enabled when the Controller status is included in
the communications data in both the originator and target node.
This variable is updated when necessary.