Category: mouse/pointing device

INT 33 - MS MOUSE - RESET DRIVER AND READ STATUS

	AX = 0000h
Return: AX = status
	    0000h hardware/driver not installed
	    FFFFh hardware/driver installed
	BX = number of buttons
	    0000h other than two
	    0002h two buttons (many drivers)
	    0003h Mouse Systems/Logitech three-button mouse
	    FFFFh two buttons
Notes:	since INT 33 might be uninitialized on old machines, the caller
	  should first check that INT 33 is neither 0000h:0000h nor points at
	  an IRET instruction (BYTE CFh) before calling this API
	to use mouse on a Hercules-compatible monographics card in graphics
	  mode, you must first set 0040h:0049h to 6 for page 0 or 5 for page 1,
	  and then call this function.	Logitech drivers v5.01 and v6.00
	  reportedly do not correctly use Hercules graphics in dual-monitor
	  systems, while version 4.10 does.
	the Logitech mouse driver contains the signature string "LOGITECH"
	  three bytes past the interrupt handler; many of the Logitech mouse
	  utilities check for this signature.
	Logitech MouseWare v6.30 reportedly does not support CGA video modes
	  if no CGA is present when it is started and the video board is
	  later switched into CGA emulation
SeeAlso: AX=0011h,AX=0021h,AX=002Fh,INT 62/AX=007Ah,INT 74