Bitfields for general mouse driver information:
Bit(s)	Description	)
 15	driver loaded as device driver rather than TSR
 14	driver is newer integrated type
 13,12	current cursor type
	00 software text cursor
	01 hardware text cursor (CRT Controller's cursor)
	1X graphics cursor
 11-8	interrupt rate (see #03176)
 7-0	count of currently-active Mouse Display Drivers (MDD), the newer
	  integrated driver type