Manual Tag Reads
Reading from a Single Tag
Reading a Tag from a script is accomplished with the
system.tag.read() function, which requires the Tag path you wish to read from. Note, that this function returns a 'Qualified Value', this object is more than just the value. A Qualified Value is the Tag value that has three attributes; Value, Quality, and TimeStamp. If you are getting multiple attributes, make sure to read the Tag once and not once for each attribute.
Reading from Multiple Tags
In the event you need to read from a large number of Tags, it is more efficient to use
system.tag.readAll() instead which reads a Python List of Tag Paths.
Relative Tag Paths
Like elsewhere in Ignition, relative paths may be used from within a script. This is especially useful when writing a Tag Event script inside of a UDT, as you can specify relative members in the same UDT with "[.]".
Manual Tag Writes
Writing to a Single Tag
Writing to a Tag with the
system.tag.write() function requires the Tag path, as well as the value you wish to write to the Tag.
Writing to Multiple Tags
Writing to multiple Tags from a single script should use the
system.tag.writeAll() function, as it is more efficient than several