Date: Sun, 23 Nov 1997 15:17:15 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Fabrice ILPONSE <fabrice AT asim DOT lip6 DOT fr>
cc: djgpp users group <djgpp AT delorie DOT com>
Subject: Re: DJGPP too slow!
In-Reply-To: <34755A66.1845@trash.lip6.fr>
Message-ID: <Pine.SUN.3.91.971123151656.19570P-100000@is>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
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On Fri, 21 Nov 1997, Fabrice ILPONSE wrote:

> 		- switch to video mode 320x200x256
> 		- loop
> 			- change color 0 to red
> 			- BLIT
> 			- change color 0 to black
> 			- wait retical retrace
> 
> 	I've got a 486 DX2 66.
> 
> 	Results:
> 		- BC 16 bits red takes  40% of screen height
> 		- BC 32 bits 45 - 50%
> 		- DJGPP      90 - 95%

Sorry, these numbers are meaningless for me.  Please post the program
(I hope it's not too large) and the gcc command line used to compile
and link it.  Without that, I cannot even understand what does ``red
takes 40% of screen height'' mean, let alone judge the differences
(why is 95% worse than 45%?).

Testing on different hardware and software configurations would also
make the data more reliable (e.g., it could be a bug in your video
adapter).

> 	Protected mode perhaps!

Protected mode should have no impact on accessing a given address.
Such accesses don't require a mode switch (unless you run under
something other than plain DOS, in which case please describe your
platform).