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Version: 8.1


This function is used in Python Scripting.


Asynchronously writes values to tags at specified paths. The script will not wait for the write operation to complete before moving on, but you can provide a callback function to run further code after the write has finished.

For a blocking tag write operation, see system.tag.writeBlocking.

Client Permission Restrictions

Permission Type: Tag Editing

Client access to this scripting function is blocked to users that do not meet the role/zone requirements for the above permission type. This function is unaffected when run in the Gateway scope.


system.tag.writeAsync(tagPaths, values, [callback])


ListtagPathsA List of tag paths to write to. A tag property can be included in the path. If no property is specified in a tag path, the Value property is assumed.
ListvaluesThe values to write to the specified paths.
CallablecallbackA function that will be invoked after the write operation is complete. The function must take a single argument: a List of QualityCode objects corresponding to the results of the write operation. [optional]




Gateway, Vision Client, Perspective Session

Code Examples

Example #1 - Write to Multiple Tags
paths = ["[default]Tag1", "[default]Folder/Tag2"]
values = [10, 10]
system.tag.writeAsync(paths, values)
Example #2 - Using a Callback Function
paths = ["[default]Tag1", "[default]Folder/Tag2"]
values = [10, 10]

def myCallback(asyncReturn):
for result in asyncReturn:
# Do something if a bad qualified value was returned
if not result.good:
print result

system.tag.writeAsync(paths, values, myCallback)


system tag writeAsync, tag.writeAsync