Int 15 Fn 84  - V20-xt-bios - Joystick Support                             [b]

   AH = 84h
   DX = subfunction
       0000h read joystick switches

       Return: AL bits 7-4 = switch settings
       other: read positions of joysticks as indicated by bits 0-3

       Return: AX = X position of joystick A (if DX bit 0 set)
           BX = Y position of joystick A (if DX bit 1 set)
           CX = X position of joystick B (if DX bit 2 set)
           DX = Y position of joystick B (if DX bit 3 set)

Return: CF set on error
       AH = status (see #0422)
   CF clear if successful
Program: V20-XT-BIOS is a ROM BIOS replacement with extensions by Peter
      Koehlmann / c't magazine

See Also: AH=84h"PS",INT 10/AH=0Eh/CX=ABCDh