Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!asuvax!mcdphx!mcdchg!documail!rich
From: rich@documail.UUCP (Rich McCallister)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Q: AMAZ. COMP. A1000 RAM EXPANSION HACK
Summary: Kickstart mod and addmem mod
Message-ID: <316@documail.UUCP>
Date: 20 Mar 91 15:19:15 GMT
References: <7229.27ca4872@cc.curtin.edu.au> <307@documail.UUCP> <10677.27de9c8f@zeus.unomaha.edu>
Organization: Bell & Howell DocuMail Division, Evanston, Ill.
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    The 1.3 Kickstart disk can be modified to both
      1) Work with the Chris Erving / Amazing Computing memory hack, and
      2) Boot off DF1:

    For a while, I was booting my 1000 with the Chris Erving memory (at
80000 to fffff hex) off DF1:. I simply applied the patches for the DF1: boot
to my Kickstart disk that was already modified to boot safely with the Chris
Erving memory. I was lucky, in that the two patches happened to not patch
the same location twice!
    The same kickstart patch I use should work for you. That's because it
basically tells the system that CHIP RAM is on the range 0 to 7ffff only,
rather than the normal 0 to 1fffff. Thus, it places both my memory (at
80000 to fffff) and yours (at 100000 to 17ffff, if I recall) outside of
CHIP RAM, which is what we want.
     When you boot with such a patched Kickstart disk, the system thinks it
has 512K of CHIP RAM, and doesn't know at all about your Chris Erving memory.
Thus, you need to use addmem to add it to the system list of free memory.
I THINK you can use the normal addmem for this; I believe it just adds the
memory to the FAST RAM free list. (I'm not positive at the moment about this.
I've always used a custom addmem that did not do any memory diagnostics,
because I used to use a recoverable RAM disk. Regular addmem would write into
some or all of the memory, wiping out my recoverable RAM disk. Out of inertia,
I think I still use the modified version.)
     If you need them, I have
        1) the instructions for patching Kickstart to ignore CHIP RAM above 512K
        2) the name of the Kickstart DF1: patch I am using
        3) the source for the modified addmem (which I think you don't need)
and I'll be happy to dig these out of my mounds of rubbish at home.
    By the way, I fell funny about using "Chris Erving" as an adjective. It is
a bit of an honor, tho, just as "Ward Christiansen" protocol is.