INT 10 - VIDEO - SELECT DRAWING FUNCTION (Hercules GRAFIX)
        AH = 44h
        AL = drawing function
            00h clear pixels
            01h set pixels
            02h invert pixels
Desc:   specify how graphics output will change the display
SeeAlso: AH=45h,AH=46h,AH=4Ch,AH=4Dh

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