INT 4A - TI Professional PC - KEYBOARD - GET KEYPRESS

	AH = 00h
Return: AX = keystroke (AH=00h for ASCII keys -- no scan code)
SeeAlso: AH=01h,AH=02h,AH=03h,AH=04h,AH=05h,INT 16/AH=00h
SeeAlso: INT 47"TI Professional",INT 48/AH=00h"TI Professional"
SeeAlso: INT 49/AH=01h"TI",INT 4C"TI Professional",INT 4D/AH=00h
SeeAlso: INT 5B"TI Professional"