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From: benefiel@wyse.wyse.com (Daniel Benefiel xtmp x2531 dept234)
Newsgroups: comp.windows.ms.programmer
Subject: Low-Level Operations in Windows
Message-ID: <3203@wyse.wyse.com>
Date: 24 Jun 91 18:19:14 GMT
Organization: Wyse Technology, San Jose
Lines: 24

I'm building a Windows utility which will be run very infrequently.

The program must do some software INTs to call BIOS routines.  The BIOS
routines, in turn, will do some I/O to devices built into the chipset.
Also, either the application or a BIOS routine will need to read from
the BIOS data segment at 400h.

The first, small, problem, is that I need to link-in an assembly
routine similar to MSC's INT86 (I need to modify BP before the INT, and
check it after).  I can probably figure out how to combine C and assembly,
but if you'd like to comment...

The second, bigger problem is that Windows in protected mode won't like
this low-level stuff.  How, then, is it done?  I suppose drivers are given
I/O privilege and a segment descriptor to access all of RAM directly,
but is this what I have to do?

Since this is my first Windows application (outside of book examples) I
haven't gotten into DLLs or drivers yet, but if they have some bearing,
please explain.

Thanks!

Dan