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From: alun@neabbs.UUCP (ALUN SAUNDERS)
Newsgroups: comp.sys.ibm.pc
Subject: Protected mode and PC/XT cards
Message-ID: <158322@neabbs.UUCP>
Date: 1 Jun 89 21:27:20 GMT
Organization: NEABBS multi-line BBS +31-20-717666 (13x), Amsterdam, Holland
Lines: 14

Can anyone tell me what happens to memory on 8-bit PC/XT add-on cards
installed in a 286 or 386 machine, say video RAM, when that machine is
running in protected mode ?  Since the card is only seeing the bottom
20 bits of the 24 address lines, won't the offending lump of memory
appear all over the memory map at 1Mbyte intervals and cause address
conflicts ?  This question came up in connection with a problem a
colleague of mine has adressing an encryption card under XENIX-386,
but I would have thought OS/2 would have the same problem.
 
Please excuse me if this is a silly question, or has been asked
before, but its been bugging me for a day or two.
 
Alun Saunders
NEABBS Amsterdam Holland