Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!ncar!ames!amdcad!pepsi!ching
From: ching@pepsi.amd.com (Mike Ching)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Remapping AT memory
Message-ID: <1990May31.061805.15760@bach.amd.com>
Date: 31 May 90 06:18:05 GMT
References: <1255.26634CFE@gisatl.FIDONET.ORG>
Sender: usenet@bach.amd.com (NNTP Posting)
Organization: Advanced Micro Devices; Sunnyvale, CA
Lines: 24

In article <1255.26634CFE@gisatl.FIDONET.ORG> david@gisatl.FIDONET.ORG (David Deitch) writes:
>In a message of <May 28 17:06> Mike Ching (ching@pepsi.amd.com ) writes:
>
> > My AT has forgotten how to map memory from 640K-1M to extended
> > memory. Can anybody help?
> > 
> > disaster. Help!
[ most of my original post deleted]
>
>     Mike, most likely you have accidentally reset the base system memory 
>switch on your motherboard.  Check your docs and make sure it is set for 
>640K system memory.
>

Sadly I've already tried setting memory to 640K (out of desperation) and
it turns the memory to a total of 640K with the other 384K ignored. I
KNOW the mapping feature can be enabled/disabled, just not how to do
it. The C&T data sheets only address hardware and say nothing about
programming the chips. I guess it's not necessary to publish anything
if there are only a handful of BIOS programmers who need to know. I
guess memory is cheap enough to throw away 384K but it's annoying to
know it's there and SHOULD be available.

Mike Ching