INT 61 - OPTIMA 1024 VGA-Sync - QUERY ZOOM WINDOW
        AX = 0005h
        BX:CX -> buffer for window parameters (see below)
Note:   INT 61h is the default interrupt; the actual interrupt number can be
          obtained by calling INT 16/AH=FFh
SeeAlso: INT 61/AX=0000h"OPTIMA",INT 61/AX=0003h"OPTIMA"

Format of window parameters:
Offset  Size    Description
 00h    WORD    X start of zoom window
 02h    WORD    Y start of zoom window
 04h    WORD    X end of zoom window
 06h    WORD    Y end of zoom window
 08h    WORD    current zoom factor
 0Ah    WORD    zoom offset start X
 0Ch    WORD    zoom offset start Y