From:	Myke AT cyberdude DOT com (Ricardo Cunha)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Vesa 2.0 is slower than 1.2 on my video card !!!!!
Date:	Thu, 24 Jul 1997 20:14:07 GMT
Message-ID:	<33d79d82.403618@news1.telepac.pt>
References:	<199707221500 DOT IAA26318 AT adit DOT ap DOT net> <h9b6bEAOrn1zEwLf AT netbook DOT demon DOT co DOT uk>
NNTP-Posting-Host:	ep3-p10.telepac.pt
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

>No SIR!
>VESA is a software API. SDD >is< VESA 2.0, not an emulation.
>The difference between SDD and your card is that SDD goes TSR, but your
>card is in ROM from the start.
>
>Guess why it's in ROM, folks.. it's software :)
>VESA is an API, which means that instead of having a gazillion different
>calls to put a pixel on a screen, you only do one, and VESA picks the
>right one for your video card.
>
>VESA translates, but not from 2.0 > 1.2 - it translates VESA calls to
>direct hardware writes.

That's right but...

When a board suports Vesa 2 Vesa calls to direct hardware writes but a
board only supports Vesa 1.2 and we use a emulator then the emulator
translates Vesa 2 Calls to Vesa 1.2 and send the information to the
board that calls direct hardware calls. As you see the emulator spends
time converting from Vesa 2 to Vesa 1.2

P.S: Sorry for may lausy english
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Ricardo Cunha
myke AT cyberdude DOT com
http://www.geocities.com/Area51/Cavern/7471
ICQ: 2217830
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