Int 49 Fn 0001  - Magic V1.16+ - Turn On Magnification                     [a]

   AX = 0001h

Return: AX = status (see below)
   BX,CX,DX destroyed
Program: MAGic (MAGnification In Color) is a TSR by Microsystems Software, Inc.
     providing 2x2 text and graphics magnification on VGA, XGA, and SVGA

Note:  INT 49 is the default, but may be overridden on the commandline.  The
     actual interrupt in use may be found by searching for the signature
     "MAGic" or "xMAGic" (for the deluxe version) immediately preceding
     the interrupt handler (this is also the installation check).  MAGic
     uses CodeRunneR, which places the signature "RT" at offset 0000h in
     the interrupt handler's segment, followed by MAGic's TSR ID of
     "VMAG".

See Also: AX=0002h,AX=0003h,AX=0004h,AX=0008h
Index: installation check;MAGic

Values for status:
 0000h cannot magnify current video mode
 0002h magnified (text mode)
 0003h magnified (graphics mode)
 FFFDh function works only in magnified mode
 FFFFh MAGic busy, retry later