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0040h:00A8h           Double-Word Pointer to Video Parameters for the EGA

    Length: 4 bytes

    This double-word pointer points to a list of pointers that contain
    various parameters and overrides for the Enhanced Graphics Adapter
    (EGA).

    ------------------------------------------------------------------
    Table Pointed to by Double-Word at 0040h:00A8h

      Offset  Size (bytes)  Description
      00h         4        Video Parameter Table Pointer
      04h         4        Dynamic Save Area Pointer
      08h         4        Alpha Mode Auxiliary Character Generator Pointer
      0Ch         4        Graphics Mode Auxiliary Character Generator Pointer
      10h         4        Reserved (always 00:00h)
      14h         4        Reserved (always 00:00h)
      18h         4        Reserved (always 00:00h)

    ------------------------------------------------------------------
    Video Parameter Table Pointer (Double-Word)

    This double-word pointer is initialized to point to the BIOS video
    parameter table.

    ------------------------------------------------------------------
    Dynamic Save Area Pointer (Double-Word)

    This double-word pointer is optional, hence it is initialized to
    00:00h. When used, this pointer points to a RAM table where
    specific dynamic values are saved. Currently the values are
    defined as follows:

        Offset  Size (bytes)    Description
        00h     16              16 EGA palette register values
        10h     1               Overscan value
        11h     239             Reserved

    ------------------------------------------------------------------
    Alpha Mode Auxiliary Character Generator Pointer (Double-Word)

    This double-word pointer is optional; hence it is initialized to
    00:00h. When used, this pointer points to a table as defined
    below:

    Offset    Size (bytes)      Description
    00h            1            Bytes per character
    01h            1            Block to load (0=normal operation)
    02h            2            Count to store (256=normal operation)
    04h            2            Character offset (0=normal operation)
    06h            4            Double-word pointer to Font Table
    0Ah            1            Maximum displayable rows (If FFh,
                                maximum rows calculated)
    0Bh            n            'n' bytes consisting of different
                                mode values for this font.
                                (0FFh is terminator)

    ------------------------------------------------------------------
    Graphics Mode Auxiliary Character Generator Pointer (double-word)

    This double-word pointer is optional; hence it is initialized to
    00:00h. When used, this pointer points to a table as defined
    below:

        Offset    Size (bytes)      Description
        00h            1            Displayable rows
        01h            2            Bytes per character
        03h            4            Double-word pointer to Font Table
        07h            n            'n' bytes consisting of different
                                    mode values for this font.
                                    (0FFh is terminator)