Use the Call Stack menu on the main window to do the following:

  Action               Function
  -------              ---------

  None                 Identifies the routine whose source code is
                       executing in the source view.

  Pull-down            Identifies the sequence of routines on the
     menu              call stack.

  Click on             Sets the context (scope) for source display,
     routine           instruction display, register display,
     name              and symbol searches to any routine on the
                       call stack.