> How about a driver (possibly DISPLAY 2.0 ;-)) that replaces CON, and does
> this hook the int10h, and implement all the text mode stuff in graphics
> mode?
> It might work...

Except with (very common) applications that write directly to the video
adapter memory. For these, a virtual screen using 386+ paging mechanism
would be required: accesses to text mode video memory cause page faults,
translated to graphics mode (Unicode) character reads or writes by a
suitable fault service routine. And for (probably much less common)
applications that use CRTC registers instead of BIOS for setting cursor
position and shape, etc., one would also have to virtualize CRTC I/O
ports using I/O permission bitmaps. Plus everything needed to fool the
applications (like BIOS variables) and make them think they operate in
text mode. Like a "windowed" DOS session.

Michal

--
BTTR Software (http://www.bttr-software.de/)



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