Play tones

        Entry:
          AH = 73h
          CX = number of tones to play
          DS:SI -> array of tones (see below)

        Note:   FAKEY is a keystroke faking utility by
                System Enhancement Associates

        Format of tone array entries:

        Offset  Size    Description
         00h    WORD    divisor for timer channel 2
         02h    WORD    duration in clock ticks