Introduction To Tag Data Links; Tag Data Links - Omron CJ1W-EIP21 Operation Manuals

7 Tag Data Link Functions
7-1

Introduction to Tag Data Links

7-1-1

Tag Data Links

Tag data links enable cyclic tag data exchanges on an EtherNet/IP network between Controllers or
between Controllers and other devices. Variables are assigned to tags. (You can also assign I/O mem-
ory addresses to tags.) The settings for tag data links are made with the Network Configurator. Refer to
7-2 Setting Tag Data Links for information on how to make the settings.
With a tag data link, one node requests the connection of a communications line to exchange data with
another node. The node that requests the connection is called the originator, and the node that receives
the request is called the target.
NJ-series CPU Unit (Built-in EtherNet/IP port)
Var_In_a
I/O refreshed. I/O refreshed.
Var_In_b
Var_In_c
Var_Out_d
Var_Out_e
I/O refreshed. I/O refreshed.
Var_Out_f
Controller status
For communications between Controllers, the connection information is set in the EtherNet/IP Unit of
the Controller that receives (consumes) the data (i.e., the originator).
Additional Information
For communications between a Controller and an I/O device, the connection information is set in
the EtherNet/IP Unit that is the originator. If an I/O device is used, the Network Configurator must
have an EDS file installed that includes connection information for the I/O device. Refer to A-2
EDS File Management for the installation procedure.
The output words and input words for each node for which data is exchanged are set in the connection
information. These words are called the output tag set and input tag set. A tag set must specify at least
one tag. The size of the data for data exchange is the total size of the tags included in the tag set. The
size of the output tag set and the size of the input tag set must match.
7-2
Input
Connection
Tag set name: ABC
• Var_In_a
Input tags Output tags
• Var_In_b
• Var_In_c
Originator
Output
Connection
Tag set name: XYZ
• Var_Out_d
Input tags
Output tags
• Var_Out_e
• Var_Out_f
Target
EtherNet/IP EtherNet/IP
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)
EtherNet/IP Unit
NJ-series CPU Unit
Outputs
Tag set name: OUT1
Var-Out1
• Var-Out1
• Var-Out2 Var-Out2
• Var-Out3 I/O refreshed. I/O refreshed.
Var-Out3
Target
Input
Var_In_d
Var_In_e
Tag set name: IN1
I/O refreshed. I/O refreshed. Var_In_f
• Var_In_d
• Var_In_e
• Var_In_f
Originator
Controller status