Communication drivers
Use communication drivers to establish connections with controllers and import tags. Use controller tags to design application logic.
Communication driver objects
Each communication driver consists of the following objects hierarchy:
- Communication driver. Represents a communication protocol.
- Communication station. Represents a physical controller.Communication drivercan contain multipleCommunication stationobjects.
- Tags. Contains tags imported from the controller.Each imported tag creates a corresponding Tag project variable. The values and data types of Tag variables remain synchronized with the values of the tags on the controller at runtime in read mode and in write mode. Tags can contain folders and other tags.TIP: When the controller Tag Data Type does not match an OPC UA standard Data Type, the most relevant OPC UA Data Type is set for the variable.
- Types. Contains types imported from the controller.
- TagImporter. Depending on theCommunication driver, allows you to import tags from controllers in the online or offline mode.Use the offline mode to import a file with tags exported from the controller. Use the online mode to establish a connection with the controller in the network and import tags from the controller.
You can communicate with controllers that support custom protocols through the serial interface by using the
Serial port
communication driver. For advanced implementations, you can use dedicated C# APIs. See C# API reference.Runtime communication
Keep the values and data types of the imported tags synchronized with the controller. Tags synchronize at regular intervals based on the
Dynamic variables polling time
value of Presentation Engines.To optimize read/write operations,
FactoryTalk Optix Studio
synchronizes the tags displayed or written through the active graphical objects. To save bandwidth, controller tag values update at runtime only when FactoryTalk Optix Applications
display the tags values.