Additional programming information on the gameport device can be found in
the include files and the Autodocs for the gameport and input devices.
Both are contained in the Amiga ROM Kernel Reference Manual: Includes and
Autodocs.

                       Gameport Device Information
                   -----------------------------------
                   INCLUDES       devices/gameport.h
                                  devices/gameport.i
                                  devices/inputevent.h
                                  devices/inputevent.i

                   AUTODOCS       gameport.doc