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Protected mode setting of video modes(without BIOS)
https://forum.osdev.org/viewtopic.php?f=8&t=19210		 Page 1 of 1
Author:  earlz [ Thu Feb 19, 2009 2:31 pm ]
Post subject:  Protected mode setting of video modes(without BIOS)
Hi, I was very surprised when I went to look at drawing in protected mode http://wiki.osdev.org/Drawing_In_Protected_Mode

It is missing setting video modes without VBE or BIOS(and therefore without messy VBE crap and without real mode)

Well, I happen to have quite a bit of code for setting the video mode by writing directly to the VGA registers. Included is
[*]40x25-text
[*]40x50-text
[*]80x25-text
[*]80x50-text
[*]90x30-text
[*]90x60-text
[*]640x480x2 colors
[*]320x200x4 colors(this is not mode 0x05! there is some differences..)
[*]640x480x16 colors
[*]720x480x16 colors
[*]320x200x256 colors
[*]320x200x256 colors-mode X(I don't remember what that means though)

I also have code for modifying the font used in text modes as well as a 8x16 bitmap font(in C code) and 8x8 bitmap font.

Should I try to add this in the protected mode drawing page or make a new page?

edit:
Btw, this code was adapted from some other source. It was originally designed for real-mode, I changed it so it would work in protected mode.. I think it might be John Fine's or another one of those old OS gurus
Author:  JohnnyTheDon [ Thu Feb 19, 2009 3:47 pm ]
Post subject:  Re: Protected mode setting of video modes(without BIOS)
That stuff is on the VGA page: http://wiki.osdev.org/VGA_Hardware
Author:  Combuster [ Thu Feb 19, 2009 5:42 pm ]
Post subject:  Re: Protected mode setting of video modes(without BIOS)
I added a link and updated the page - apparently "writing a driver" was assumed to be too obvious to mention.

As for Mode X - it has two (mixed) meanings. It either refers to
- Any planar 256 color mode (i.e. unchained with access to 256k video memory)
- Specifically the 320x240x8 mode, again unchained
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