From:	"Rob van Berkel" <rvberkel AT EuroNet DOT NL>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: HELP: VESA Mapping Linear frame buffer in inline assembler
Date:	8 May 1998 10:41:36 GMT
Organization:	EuroNet Internet
Lines:	20
Message-ID:	<6iunh0$1ev@news.euro.net>
References:	<6iubuf$6ir$1 AT news DOT cowan DOT edu DOT au>
NNTP-Posting-Host:	i049.ztm.euronet.nl
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

I guess you should first allocate a descriptor. Maybe this examplecode I use
helps...

if ((ldt_sel = __dpmi_allocate_ldt_descriptors(1)) == -1)
    usage("error allocating ldt_descriptor");
memset(&mi,0,sizeof(mi));
mi.address = MMIOBase;
mi.size = MMIOSize;

if (__dpmi_physical_address_mapping(&mi) == -1)
    usage("error mapping physical address");
if (__dpmi_lock_linear_region(&mi) == -1)
    usage("error locking ldt_descriptor");
if (__dpmi_set_segment_base_address(ldt_sel, mi.address) == -1)
    usage("error setting ldt segment base");
if (__dpmi_set_segment_limit(ldt_sel, mi.size - 1) == -1)
    usage("error setting ldt segment limit");

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