Date:	Fri, 23 May 2003 21:33:59 +0300
From:	"Eli Zaretskii" <eliz AT elta DOT co DOT il>
Sender:	halo1 AT zahav DOT net DOT il
To:	rogers AT westmont DOT edu
Message-Id:	<9003-Fri23May2003213358+0300-eliz@elta.co.il>
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CC:	djgpp AT delorie DOT com
In-reply-to:	<89ce6cc3.0305212135.6f123d8@posting.google.com>
	(rogers AT westmont DOT edu)
Subject:	Re: Trouble accessing DOS upper memory
References:	<89ce6cc3 DOT 0305212135 DOT 6f123d8 AT posting DOT google DOT com>
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> From: rogers AT westmont DOT edu (wfrogers)
> Newsgroups: comp.os.msdos.djgpp
> Date: 21 May 2003 22:35:44 -0700
> 
> I am trying to access 0xD000 using a simple C program compiled with
> DJGPP and am getting
> 
> Exiting due to signal SIGSEGV
> General Protection Fault at eip=0000362a
> 
> When I access video memory at 0xB800, no problem.  When I try 0xD0000,
> I either get the error, or if it works, I get data which is the same
> no matter what offset I use.  The purpose is to access data being
> written by an ISA data aquisition card.

See sections 18.4 and 18.7 of the DJGPP FAQ list, they explain these
issues.  If you have already read that and your code is supposed to do
what the FAQ suggests, please post the relevant parts of your code
here, and please post the full text of the crash message (the things
after "Gener Protection Fault...."), as that message contains
important information we need to see to help you fix your code.

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