Int 10h, 1000h          Set Palette Register                         EGA, VGA

    Sets one of the 16 palette registers ("EGA registers").

        Entry   AX = 1000h
                BL = Palette register (00h..0Fh)
                BH = Color value

        Return  Nothing

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    Each of the 16 palette registers can take on 1 of 64 values. the
    value in BH is formatted as follows:

          Bit 7 - Reserved
          Bit 6 - Reserved
          Bit 5 - Secondary Red
          Bit 4 - Secondary Green
          Bit 3 - Secondary Blue
          Bit 2 - Red
          Bit 1 - Green
          Bit 0 - Blue

    The secondary colors have an intensity of 1/3, while the normal
    colors have an intensity of 2/3. For example, BH = 02h will
    produce green, BH = 10h will produce a dim green, and BH = 12h
    will produce a bright green.

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    The default values for the palette registers are defined below:

        Palette
        Register        Color value         Color
          00h               00h             Black
          01h               01h             Blue
          02h               02h             Green
          03h               03h             Cyan
          04h               04h             Red
          05h               05h             Magenta
          06h               14h             Brown
          07h               07h             White
          08h               38h             Dark Gray
          09h               39h             Light Blue
          0Ah               3Ah             Light Green
          0Bh               3Bh             LIght Cyan
          0Ch               3Ch             Light Red
          0Dh               3Dh             Light Magenta
          0Eh               3Eh             Yellow
          0Fh               3Fh             Bright White