INT 15 - V20-XT-BIOS - JOYSTICK SUPPORT                                         
	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 #00496)
	CF clear if successful
Program: V20-XT-BIOS is a ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware.  The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. replacement with extensions by Peter
	   Koehlmann / c't magazine
SeeAlso: AH=84h"PSIBM PS/2, any model",INT 10/AH=0Eh/CX=ABCDh