Table Of Contents

Write Tag (G Dataflow)

Version:
Last Modified: October 2, 2017

Writes a data value to a tag, or to a tag proxy if it is configured to have write access.

connector_pane_image
datatype_icon

tag/proxy ref in

The reference to the tag endpoint, or tag proxy endpoint if configured to have write access, to which to write a data value.

datatype_icon

value

The data value that this node writes to the tag or tag proxy.

Data Type of value

tag/proxy ref in
datatype_icon

timestamp

The timestamp you want to associate with the data value that this node writes to the tag.

This input is available to associate a timestamp with the data only if you enable the Has Timestamps? property of the tag.

If you do not wire this input and Has Timestamps? is enabled, this node automatically generates the current timestamp and associates it with the data value in the tag.

datatype_icon

error in

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

Default: No error

datatype_icon

tag/proxy ref out

The reference to the tag endpoint or tag proxy endpoint to which this node wrote a data value.

datatype_icon

error out

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.

error in does not contain an error error in contains an error
If no error occurred before the node runs, the node begins execution normally.

If no error occurs while the node runs, it returns no error. If an error does occur while the node runs, it returns that error information as error out.

If an error occurred before the node runs, the node does not execute. Instead, it returns the error in value as error out.

What Is a Tag?

A tag is single-point, latest value data that you can access from multiple documents within a project. A tag can store a single value of any data type that represents the state of a process. Tags are similar to global variables in text-based programming languages.

You can create a tag either dynamically, using the Configure and Create Tag node on the diagram, or statically, in the shared resource collection file.

You can create a tag to access the same data from multiple VIs within a project.

What Is a Tag Proxy?

A tag proxy is a reference that is local to part of the application that mirrors the value of the actual tag to which it is linked in another location in the application. You use a tag proxy to access data that is in another location in the application. You can read from and optionally write to a tag proxy only after the tag proxy links to a tag.

Where This Node Can Run:

Desktop OS: Windows

FPGA: This product does not support FPGA devices

Web Server: Not supported in VIs that run in a web application


Recently Viewed Topics