Read Real-time Tags Synchronously

  • SyncReadTags method is a simple call you can use to read any number of Tags with a blocking call.
  • This is a blocking call and should only be called one at a time.
  • The subscription method using AddTags and the ValuesChangedAll event listed above is more efficient for reading Tag values on a continuous basis.
  • This SyncReadTags method does not make a synchronous call to the OPC Servers, it makes a temporary subscription to the OAS Services and receives the current values of the Tags.
  • No features in Open Automation Software make synchronous calls to OPC Servers, as it often causes high CPU usage and poor performance.