From:	"Mark Allanson" <mallanso AT echidna DOT stu DOT cowan DOT edu DOT au>
Newsgroups:	comp.os.msdos.djgpp
Subject:	HELP: VESA Mapping Linear frame buffer in inline assembler
Date:	Fri, 8 May 1998 15:23:53 +0800
Organization:	Edith Cowan University
Lines:	34
Message-ID:	<6iubuf$6ir$1@news.cowan.edu.au>
NNTP-Posting-Host:	whtstump.stu.cowan.edu.au
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Im having trouble mapping the Linear Frame buffer for VESA video modes, i
set the video mode fine but when i try and map the physical address of the
linear frame buffer to a linear address i am stuck! :(

i tried using the __dpmi_physical_address_mapping  function but alas with no
success.. i want to try it in assembler, my only problem is that i cant
figure out how to use inline assembler properly! any help there would be
appreciated..

here is an example of what i am trying to do


/* CUT */

   __dpmi_meminfo lfbmap;                      // mem info struct

   lfbmap.size = 4096*1024;                     // size of the memory in
bytes.. 4M
   lfbmap.address = LFBmapping.PhysBasePtr;           // the phys address to
map
   return(__dpmi_physical_address_mapping(&lfbmap));

/* CUT */

the structure   LFBmapping is the structure returned by vesa get mode info
call.. PhysBasePtr is the address of the LFB

should this work? i know its not, can anyone please shed some light as to
why?

Regards, Mark

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