Category: BIOS

INT 16 - KEYBOARD - GET EXTENDED SHIFT STATES (enh kbd support only)

	AH = 12h
Return: AL = shift flags 1 (same as returned by AH=02h) (see #00587)
	AH = shift flags 2 (see #00588)
Notes:	AL bit 3 set only for left Alt key on many machines
	AH bits 7 through 4 always clear on a Compaq SLT/286
	INT 16/AH=09h can be used to determine whether this function is
	  supported, but only on later model PS/2s
	many BIOSes (including at least some versions of Phoenix and AMI) will
	  destroy AH on return from functions higher than AH=12h, returning
	  12h less than was in AH on entry (due to a chain of DEC/JZ
	  instructions)
SeeAlso: AH=02h,AH=09h,AH=22h,AH=51h,INT 17/AH=0Dh,MEM 0040h:0017h