INT 2fH ad83H: Query KEYB.COM Country Flag

                                                         Compatibility: 5.0+ 
 Expects: AX    ad83H
 Returns: BL    flag: 00H = default keyboard
                      ffH = alternate keyboard
    Info: When KEYB.COM is active and the KEYBOARD.SYS has been installed,
          you can toggle between one keyboard layout an another via
          Ctrl+Alt+F1 and Ctrl+Alt+F2.

          The return value, in BL, identifies which keyboard layout is
          currently active. BL=00H indicates that the Ctrl+Alt+F1 (default)
          is active and BL=ffH indicates that the Ctrl+Alt+F2 (secondary)
          layout is active.

See Also: INT 2fH adxxH: KEYB.COM Functions
          INT 2fH: Multiplex Interrupt
          DOS Functions