Re: Physical addresses in protected mode?

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#7323

From: Steve Resnick
Date: Tue, 25 Jun 1991 17:49

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In article <1991Jun25.023154.16683@maytag.waterloo.edu> dmurdoch@watstat.waterloo.edu (Duncan Murdoch) writes:
>In article <4948@gumby.Altos.COM> rcollins@altos.COM (Robert Collins) writes:
>>
>>If you are in V86 mode, then give it up because you are executing at IOPL=3
>>which makes it impossible to get the physical address.
>
>If running under VCPI, there's a call to find the physical address corresponding
>to any V86 address.  This is done by calling INT 67h with AX=0DE06h, CX=the
>linear V86 address shifted right 12 bits.  It returns with EDX holding the
>physical address of the page.  I imagine DPMI has a similar service, but
>I don't have the spec.

DPMI Does support a virtual-to-physical address translation. I don't have the
spec here, but I will dig it up if someone wants the info.... Let me
know via mail ....


Steve



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Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!elroy.jpl.nasa.gov!decwrl!netcomsv!resnicks
From: resnicks@netcom.COM (Steve Resnick)
Newsgroups: comp.os.msdos.programmer
Subject: Re: Physical addresses in protected mode?
Message-ID: <1991Jun25.174941.8081@netcom.COM>
Date: 25 Jun 91 17:49:41 GMT
References: <cchapman.677508274@msd> <4948@gumby.Altos.COM> <1991Jun25.023154.16683@maytag.waterloo.edu>
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