Session States

Stopped

The session initially is created in the stopped state. In the stopped state, the session does not transfer frame values to or from the interface.

While the session is stopped, you can change properties specific to this session. You can set any Session property except those in the Interface category (refer to Stopped in Interface States).

While the session is Started, you cannot change properties of objects in the database, such as frames or signals. The properties of these objects are committed when the session is created.

Started

In the started state, the session is started, but is waiting for the associated interface to be started also. The interface must be communicating for the session to exchange data on the network.

For most applications, the Started state is transitory in nature. When you call the XNET Read, Write, or Start VI (LabVIEW) or the appropriate nxRead or nxWrite function or nxStart using defaults (C), the interface is started along with the session. Once the interface is communicating, the session automatically transitions to communicating without interaction by your application.

If you call the XNET Start VI or nxStart function with the scope of Session Only, the interface is not started. You can use this advanced feature to prepare multiple sessions for the interface, then start communication for all sessions together by starting the interface (XNET Start VI or nxStart with scope of Interface Only).

Communicating

In the Communicating state, the session is communicating on the network with remote ECUs. Frame or signal values are received for an input session. Frame or signal values are transmitted for an output session. Your application accesses these values using the appropriate or XNET Read or Write VI or function.