Path: utzoo!attcan!uunet!mcvax!ukc!reading!bru-cc!ralph
From: ralph@cc.brunel.ac.uk (Ralph Mitchell)
Newsgroups: comp.os.minix
Subject: Re: EXTENDED/EXPANDED Memory on PC's
Message-ID: <533@Terra.cc.brunel.ac.uk>
Date: 16 Jan 89 09:30:11 GMT
References: <6470@louie.udel.EDU> <4054@omepd.UUCP>
Reply-To: ralph@ccs.brunel.ac.uk (Ralph Mitchell)
Organization: Brunel University, Uxbridge, UK
Lines: 22

In article <4054@omepd.UUCP> pcm@iwarpj.UUCP (Phil C. Miller) writes:
 [discussion deleted...]
>
>In both cases, the user has the 16Mb of memory available for use; with
>expanded memory, operating systems which run in REAL mode (most notably
>DOS and MINIX) can have access to more than 640k.
>
>Phil Miller


What about the case where a PC has 3x256K ram chips.  Surely the whole
768K is contiguous memory, at least in the chips.  Are you saying that
the address selection hardware is deliberately stopping access above
640K and that there's some more hardware to map the remaining 128K
elsewhere ??  Sounds like the designer had a bad day...

Ralph Mitchell
-- 
 From:  Ralph Mitchell at Brunel University, Uxbridge, UB8, 3PH, UK
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