From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: VBE 2.0 Pmode Bank Switching...
Date:	Fri, 14 Feb 1997 20:06:51 +0000
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nikki writes:
>erm. isn't the whole point of vbe2 so you can use linear access and not
>have to use that nasty bank switching thing anymore? :)

True, but the problem is that a lot of cards still don't support linear
access. It can be faked with the virtual memory hardware, but that
requires functions that aren't available in DPMI 0.9. So until all the
world gets new graphics cards that support linear addressing, or
Microsoft gets off their asses and makes Windows support DPMI 1.0, we
have to support banked graphics modes as well as linear ones. And along
with the linear framebuffer support, VBE 2.0 provides a protected mode
bank switching mechanism that's a _lot_ faster than VESA 1.x...

/*
 *  Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
 *  Ghoti: 'gh' as in 'enough', 'o' as in 'women', and 'ti' as in 'nation'.
 */

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