INT 62 u - FGDRIVER v1.10 - "FG_GETRGB" - GET VIDEO DAC REGISTER CONTENTS
        AX = 001Ch
        ES:BX -> variable pointer record (see below)
        CX = DAC register number
Return: variables updated
Note:   this call is ignored in text modes and CGA/EGA video modes (since
          they do not use DAC registers)
SeeAlso: AX=001Dh,AX=00A4h

Format of variable pointer record:
Offset  Size    Description
 00h    WORD    segment of WORD buffer for red component of DAC register
 02h    WORD    offset of WORD buffer for red component
 04h    WORD    segment of WORD buffer for green component of DAC register
 06h    WORD    offset of WORD buffer for green component
 08h    WORD    segment of WORD buffer for blue component of DAC register
 0Ah    WORD    offset of WORD buffer for blue component