From: jbs30000 AT aol DOT com (Joel)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Mapping DOS base memory under 1 meg
Date: 1 Aug 2003 22:04:41 -0700
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To: djgpp AT delorie DOT com
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Martin Str|mberg <ams AT speedy DOT ludd DOT luth DOT se> wrote in message news:<3f2a2474$0$171$cc7c7865 AT news DOT luth DOT se>...
> Joel <jbs30000 AT aol DOT com> wrote:
> : I'm writting some SVGA code which uses banked modes if a linear mode
> : is not availible.  Now, I had an idea of, when using _farpokeb instead
> : of adding segment << 4 to the offset, which is usually A0000 + offset,
> : I would make a selector for the A000 - AFFF graphics memory buffer. 
> 
> ...
> 
> : So, is there a reliable way to make a base memory selector other than
> : just using the __djgpp_nearptr_enable() ?
> 
> You already have a selector for conventional memory in _dos_ds (or
> perhaps __dos_ds). I think this one covers addresses 0 to 1MiB+64kiB.
> 
> 
> Right,
> 
> 						MartinS

Thanks, but actually, the point of making my own descriptor is so that
the base memory starts at the graphics buffer.  That way, when using
_farpokeb for example, I don't have to add the segment << 4 to the
offset each time.