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From: dwl10@amdahl.amdahl.com (Dave Lowrey)
Newsgroups: comp.sys.cbm
Subject: Re: 1750 & C-Power 128
Message-ID: <15298@amdahl.amdahl.com>
Date: Mon, 28-Sep-87 16:23:44 EDT
Article-I.D.: amdahl.15298
Posted: Mon Sep 28 16:23:44 1987
Date-Received: Tue, 29-Sep-87 07:09:58 EDT
References: <467@polyslo.UUCP>
Reply-To: dwl10@amdahl.amdahl.com (Dave Lowrey)
Organization: Amdahl Corporation, Houston TX
Lines: 43

In article <467@polyslo.UUCP> jchikin@polyslo.UUCP (Chikin Joe) writes:
>Does anyone know if the 1750 REU can be used in conjunction with
>C-Power 128 as a ramdisk or external drive?  I have C-Power and it
>makes no reference to the 1750 as a possible device.  I noticed that
>someone modified their shell, compiler, and linker to accomodate the
>1581 drive.  Can the same be done to the C-Power 128?  Has anyone done
>it yet?  If not, does anyone have any experience with the shell's 
>programming structure?  I'll try to modify it as a last resort but
>I hope someone has rewritten the shell to be compatible with the 1750.
> 

There is a very big problem you encounter when trying to modify
the C-Power shell (at least on the 64, but I would imagine it to be
the same on the 128) is that there is very little memory avaliable
to put new code into the shell.

C-Power's shell resides in memory from $0801 to $17ff. Programs that
run under the shell are loaded starting at $1800. No room to add
any code. It wouldn't be too hard to modify the shell to load starting
at a higher address, and you can easily modify link.sh to relocate
starting at that address. But, you would then have to re-locate
cc.sh, compiler, translator, link.sh, and any other utilities that
you don't have source for to the new address. That is not easy!

Sooooo, adding anything like an REU to the shell is not an easy
thing to do. I guess if you wanted to do overlays.........

Now, it would be possible to do library routines to allow the programs
you write to have access to the REU, but that is another matter.

-- 
-------------------------------------------------------------------

                  "Familiarity breeds attempt"

                          Dave Lowrey
                          Amdahl Corp.
                          Houston, Texas
                          (713)-850-8828
                         ...!{ihnp4,cbosgd,hplabs,oliveb}!amdahl!dwl10

[ The opinions expressed <may> be those of the author and not necessarily
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