Int 10 Fn 0C  - Video - Write Graphics Pixel                               [V]

   AH = 0Ch
   BH = page number
   AL = pixel color (if bit 7 set, value is xor'ed onto screen)
   CX = column
   DX = row
Desc:  set a single pixel on the display in graphics modes

Notes: valid only in graphics modes
   BH is ignored if the current video mode supports only one page

See Also: AH=0Dh,AH=46h