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VESA vs VGA

Posted: Thu Feb 05, 2009 11:14 am
by BPearl
Hi friends,
I want to develop a video driver for protected mode.
My doubts are the following:

1. Can we use VGA functions in P-Mode?
2. What is the difference between VGA and VESA?
3. Is there any difference between a VESA and a video driver?

Thanks in advance for reply

Re: VESA vs VGA

Posted: Thu Feb 05, 2009 11:33 am
by gzaloprgm
Can we use VGA functions in P-Mode?
Not directly. Indeed, you can reprogram video controller to enter some mode. Check "Video registers" in the wiki: http://wiki.osdev.org/VGA_Hardware
2. What is the difference between VGA and VESA?
VESA is the company. VGA is the resolution.

With VBE (vesa bios extension) you can have higher resolutions (AFAIK up to 1440 x something) while vga is 640x480x16colors.
3. Is there any difference between a VESA and a video driver?
A vesa?!

Cheers
Gonzalo

Re: VESA vs VGA

Posted: Thu Feb 05, 2009 11:34 am
by Combuster