vesa text modes

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neon
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vesa text modes

Post by neon »

Hey everyone,

Is vesa text modes not as wide supported as graphics modes? I tested quite a few of different types of modes (graphical and textual) in both Bochs and VirtualPC. All graphics modes that I have tested seem to work fine. It seems any other text mode (Besides 0, 1, 2, 3, and 7) does not get set :/ Is this common? I just kind of find it odd so I wanted to ask here.

I decided to post this here as its for my protected mode boot loader.

Thanks for any responses :)
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Re: vesa text modes

Post by neon »

Little update...

Im still not sure what is going on with vesa text modes, but I decided to just use vga to set a new font. Its working fine with VirtualPC right now, but not Bochs (Its rendering garbage)...have to find out why though.

Im posting here to let everyone know that I have used a different method of obtaining the solution that I wanted (a different text mode), but I am still interested at what is going on with vesa though if anyone has any ideas. If not, thats okay ;)
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jal
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Re: vesa text modes

Post by jal »

neon wrote:Im still not sure what is going on with vesa text modes, but I decided to just use vga to set a new font. Its working fine with VirtualPC right now, but not Bochs (Its rendering garbage)...have to find out why though.
Probably a problem with switching back to the right plane access if you just have 80x25, or otherwise some bad CRT register values. There have been some recent and less recent threads (the latter ones mentioned in the recent ones) that explain how to do that stuff.
Im posting here to let everyone know that I have used a different method of obtaining the solution that I wanted (a different text mode), but I am still interested at what is going on with vesa though if anyone has any ideas. If not, thats okay ;)
When I used VESA text modes, they were readily available in all graphics cards (132x60 etc.), but that was ten years ago probably. I could imagine there's little support for them in modern cards.


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Re: vesa text modes

Post by neon »

Probably a problem with switching back to the right plane access if you just have 80x25, or otherwise some bad CRT register values. There have been some recent and less recent threads (the latter ones mentioned in the recent ones) that explain how to do that stuff.
Surprisingly the problem was none of those--It was inportb() always returning 0xff. ugh...That really missed up alot of the code. Its working fine now (for the most part) in bochs and virtual PC. Thanks for your help :D
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char c[2]={"\x90\xC3"};int main(){void(*f)()=(void(__cdecl*)(void))(void*)&c;f();}
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