INT 10 - VIDEO - MSHERC.COM - GET VIDEO ADAPTER TYPE AND MODE
        AH = EFh
Return: DL = video adapter type
            00h original Hercules
            01h Hercules Plus
            02h Hercules InColor???
        DH = memory mode byte
            01h "half" mode
            03h "full" mode
Program: MSHERC.COM is a support program for the Microsoft Quick languages which
          makes their graphics libraries compatible with a Hercules card by
          adding video modes 08h and 88h, and supporting text in the new
          graphics modes.
Notes:  while in mode 08h or 88h, INT 10 supports the Hercules card much like
          a CGA.
        MSHERC performs an installation check by setting DL=FFh and testing
          whether it has been changed on return
Index:  installation check;MSHERC

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