On Aug 29, 2013, at 9:55 AM, David Woodhouse <[email protected]> wrote:
>> >> Then there are problems with getting the hardware into the correct >> state. Like needing a BIOS Option ROM to get the video controller in >> VGA mode (DOS code can poke the video memory directly). > > Well, if your app really assumes VGA hardware and was broken with > EGA/MDA/etc then yes, that'll suck. But if you have a proper video BIOS > for the hardware, or if you can just use ask UEFI for a linear > framebuffer and then provide INT 10h services using that, you may be > able to achieve something useful. EGA, good old 1984 technology from my collage days... The 80x25 text mode buffer at 0xB8000–0xBFFFF goes all the back to Black and White Hercules days. Back in the 1980's the UI would be slow if you did INT 10, so best practice was to have your 16-bit real mode assembly code poke the text mode frame buffer directly. I wrote some BIOS serial redirection code back in the 1990's and I had to track the deltas in the video buffer and send those deltas out as PCANSI escape sequences. So INT 10 by its self is not enough. I'm also guessing that this magic DOS program is some kind of diagnostic or manufacturing tool, so running it under an OS VM may not let it touch hardware like it needs to. Thanks, Andrew Fish ------------------------------------------------------------------------------ Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! Discover the easy way to master current and previous Microsoft technologies and advance your career. Get an incredible 1,500+ hours of step-by-step tutorial videos with LearnDevNow. Subscribe today and save! http://pubads.g.doubleclick.net/gampad/clk?id=58040911&iu=/4140/ostg.clktrk _______________________________________________ edk2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/edk2-devel
