Model callbacks are sequences entry point sequences call and client sequence files can override. Use Model callbacks to customize the behavior of a process model for each client sequence file that uses the process model. By defining one or more Model callbacks in a process model file, you specify the set of process model operations you can customize from a client sequence file.

Complete the following steps to define a Model callback.

1. Add a sequence to the process model file.
2. Select Edit»Sequence Properties to launch the Sequence Properties dialog box.
3. Click the Model tab.
4. Select Callback from the Type ring control.
5. Click OK.
6. Call the new sequence you just created from the process model.

You can override a callback in the process model sequence file by using the Sequence File Callbacks dialog box to create a sequence with the same name but different functionality in the client sequence file. Select Edit»Sequence File Callbacks to launch the Sequence File Callbacks dialog box.

Some Model callbacks, such as the TestReport callback in the default process model, are sufficient for handling specific types of operations. Other Model callbacks are placeholders you override with sequences in the client sequence file. For example, the MainSequence callback in the default process model file is a placeholder for the MainSequence callback you create in the client sequence file.

A primary process model file can directly call model callbacks in a secondary process model file. At run time, if the client sequence file of the primary file implements a callback defined in the secondary process model file, TestStand invokes the callback in the client sequence file, even if the primary process model file does not define the callback. You must add a copy of the callback to the primary model file for the callback to appear in the Sequence File Callbacks dialog box for the client sequence file.