INT 14h,  0Dh    Keyboard read without wait

      Entry:  None

      Exit:   AX         IBM-style scan code (Character available)
                         FFFFh               (Character not available)

    Return in  AX the  next character  (non-destructive read ahead)  from the
    keyboard; if nothing is currently in the keyboard buffer, return FFFFh in
    AX.   Use IBM-style  function  key mapping  in the high order byte.  Scan
    codes for non-"function" keys  are not specifically required,  but may be
    included. Function keys return 00h in AL and the "scan code" in AH.