From: "Charles Sandmann" <sandmann AT clio DOT rice DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Q: How can I access to HMA with CWSDPMI ?
Date: Sat,  6 Sep 1997 11:23:56
Organization: Aspen Technology, Inc.
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Message-ID: <34113d4c.sandmann@clio.rice.edu>
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>    so trying simply to get a selector, set the base to 0x1a000 and its 
>    limit to above what I need is not enough.
>    I get a page fault when trying to access this memory.

If VCPI is not used to swap modes, CWSDPMI does not map the HMA memory
in the pagetables.  This is a bug.in paging.c.  As a workaround the
memory can be mapped via the DPMI 0x800 call.  I'll fix it in the next
release.