Message-ID: <35DA8319.B27A2AD8@geocities.com>
From: Merlin <merlin__ AT geocities DOT com>
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Newsgroups: comp.os.msdos.djgpp
Subject: Re: VESA: hints, clue but no examples
References: <1998081519323200 DOT PAA25189 AT ladder01 DOT news DOT aol DOT com> <35D66C0C DOT 8D8F94C8 AT geocities DOT com> <35D70CC1 DOT BCA4F4EF AT unb DOT ca> <35D93933 DOT 40CF1D5 AT geocities DOT com> <35D98CF1 DOT F906723E AT unb DOT ca>
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Date: Wed, 19 Aug 1998 07:51:18 GMT
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To: djgpp AT delorie DOT com
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Endlisnis wrote:

> Merlin wrote:
>
> > >     To get the 256-byte buffer, you need to use the Transfer Buffer, this is very
> > > well documented in the FAQ. (Section #18.2 How to use buffers with DOS/BIOS
> > > services).
> > ahh..ok thanks...i'll take a look at that...
> > do all vesa 1.2 modes use bank switching?
> >       Merlin.
>
>     Not nessecarily, but yes.  There do exist VESA 1.2 modes, usually card specific ones
> that don't need bank-switching.  My ATI card supports VESA 320x200x256 where bank
> switching isn't nessecary unless you want to do hardware scrolling.

> Some SVGA cards

> (Tridents) also support SVGA Text modes which don't require bank switching, but for all
> intensive purposes, you should expect all VESA 1.2 modes to requires bank-switching.  To
> make things even worse, if you are in a 24-bit mode, a bank can switch in the middle of
> the 24-bits.

banks switch every 64k right?

Where do you think i should start:
using the linear frame buffer in vbe2.0
or
using bank switching in vbe1.2

i suppose i'll eventually hve to learn both (i have a feeling bank switching and vbe1.2 are
still going to be around for a while) but which is better to begin with..ie easier...?

l8r.
    Merlin.