DataChange
Occurs with connected objects when the VALIDATE method of one of the objects in any process managing the same data name is used to update the current data values. The new data replaces the previous one, and can then be accessed using the READ method. The old data can no longer be accessed, whether or not it has been processed.
This event does not occur during the connection procedure, and does not occur if the EventReception parameter was *FALSE at the time of connection.
When executed, if the process related to the event has not ended by the time the next event occurs, the new event is placed in a queue and run as soon as the current process ends. If a backlog of events develops, processing them can give the user the impression that the interface has frozen.