INT 33 - MS MOUSE v1.0+ - DEFINE INTERRUPT SUBROUTINE PARAMETERS                
	AX = 000Ch
	CX = call mask (see #03171)
	ES:DX -> FAR routine (see #03172)
SeeAlso: AX=0018h


Bitfields for mouse call mask:
Bit(s)	Description	(Table 03171)
 0	call if mouse moves
 1	call if left button pressed
 2	call if left button released
 3	call if right button pressed
 4	call if right button released
 5	call if middle button pressed (Mouse Systems/Logitech/Genius mouse)
 6	call if middle button released (Mouse Systems/Logitech/Genius mouse)
 7-15	unused
Note:	some versions of the Microsoft documentation incorrectly state that CX
	  bit 0 means call if mouse cursor moves


(Table 03172)
Values interrupt routine is called with:
	AX = condition mask (same bit assignments as call mask)
	BX = button state
	CX = cursor column
	DX = cursor row
	SI = horizontal mickey count
	DI = vertical mickey count
Notes:	some versions of the Microsoft documentation erroneously swap the
	  meanings of SI and DI
	in text modes, the row and column will be reported as a multiple of
	  the character cell size, typically 8x8 pixels
                                                                                

INT 33 - CuteMouse 2.1b4+ - Define User Interrupt Routine                       
        AX = 000Ch

Notes:  on entry, bit 7 of CX (call mask) indicates that the user routine
        will be called on a wheel movement.
        the user routine will be called with BH holding the 8-bit signed
        counter of wheel movement since the last call to the routine.