Int 10 Fn 44  - Video - Hercules Grafix - "level" - Select Drawing Functi  [V]

   AH = 44h
   AL = drawing function
       00h clear pixels
       01h set pixels
       02h invert pixels

Return: nothing
Desc:  specify how graphics output will change the display

See Also: AH=45h,AH=46h,AH=4Ch,AH=4Dh