Category: BIOS

INT 16 - KEYBOARD - CHECK FOR KEYSTROKE

	AH = 01h
Return: ZF set if no keystroke available
	ZF clear if keystroke available
	    AH = BIOS scan code
	    AL = ASCII character
Note:	if a keystroke is present, it is not removed from the keyboard buffer;
	  however, any extended keystrokes which are not compatible with 83/84-
	  key keyboards are removed by IBM and most fully-compatible BIOSes in
	  the process of checking whether a non-extended keystroke is available
	some (older) clone BIOSes do not discard extended keystrokes and manage
	  function AH=00h and AH=10h the same
	the K3PLUS v6.00+ INT 16 BIOS replacement doesn't discard extended
	  keystrokes (same as with functions 10h and 20h), but will always
	  translate prefix E0h to 00h. This allows old programs to use extended
	  keystrokes and should not cause compatibility problems
SeeAlso: AH=00h,AH=11h,AH=21h,INT 18/AH=01h,INT 09,INT 15/AH=4Fh