Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!pt.cs.cmu.edu!sei!bwb
From: bwb@sei.cmu.edu (Bruce Benson)
Newsgroups: comp.sys.ibm.pc
Subject: Re: >640k Memory question
Message-ID: <7347@fy.sei.cmu.edu>
Date: 28 May 90 16:04:38 GMT
References: <15007@reed.UUCP>
Reply-To: bwb@sei.cmu.edu (Bruce Benson)
Organization: Software Engineering Institute, Pittsburgh, PA
Lines: 41

In article <15007@reed.UUCP> minar@reed.bitnet (Nelson Minar) writes:
>
>Following my having to get my el-cheapo clone maker to put RAM chips fast
>enough for my AT in, I find myself the proud owner of an extra 384K on my AT
>clone.
>
>My question is, what do I do with this oh-so-wonderful extra memory?

Unless you have something like the Chips and Technology chip set, this extra
memory is just plain extended memory.  It is mapped at 1Meg thru 1.384 Meg.

>what programs support it? I'm aware of QEMM, which loads TSRs into this
>upper space.  I also have several disk cache programs that use this space,

Any program that will use extended memory: disk cache, EMS emulator, XMS
driver, DOS extenders, etc.  If your chipset supports use of this memory
as hardware EMS, than you should have gotten a software driver for this. Check
the manuals/doc that came with your clone (I'm assuming you just got this
machine, in which case you may have a modern chipset).

>what is the name for AT memory > 640k? Its the standard on-the-motherboard
>stuff. Does anyone use the other type of memory any more?

As per above, it may be on the motherboard, but it is mapped to over 1 Mb or
is EMS hardware and hence mappable to any area including 640K to 1Mb.  If
this memory was really hardwired from 640K to 1Mb than it would conflict
with your display ram/rom and system rom chips.  I doubt your machine would 
run at all.

>From the programmer end of things -
>
>how do I address it? Are there any good references on using this memory for
>data space?

Anything on use of EMS, extended memory, XMS standard will be useful.  See
you local computer oriented books store.

Conclusion: this is not some kind of special ram, but just the same old
ordinary stuff you always here about.  Find out what kind it is.

Bruce