Path: utzoo!attcan!uunet!mcvax!unido!tub!tmpmbx!netmbx!hase
From: hase@netmbx.UUCP (Hartmut Semken)
Newsgroups: comp.sys.atari.st
Subject: Re: Upgrading over 4 megs
Message-ID: <2115@netmbx.UUCP>
Date: 17 Jul 88 23:14:54 GMT
References: <880714032327.837790@HIS-PHOENIX-MULTICS.ARPA>
Reply-To: hase@netmbx.UUCP (Hartmut Semken)
Organization: netmbx Public Access Unix, Berlin
Lines: 19

In article <880714032327.837790@HIS-PHOENIX-MULTICS.ARPA> Friesen%PCO@BCO-MULTICS.ARPA writes:
>Ok, now we know it is possable, but could some kind soul tell us how.  

I'll try.

I did it. It's not that hard if you have a RAM board you can access like
static RAM (a SRAM board or a DRAM board with local refreshing
circurit).
Just connect that to the adress and data bus, and provide DTACK to the
DTACK line, so the GLUE chip will not issue a BUSERR.

The tricky bit is the software. GEMDOS can use 4 MB, not more. The
cusrom chips are the same, they can't use the RAM behind 400000 Hex
(right, Atari?). A patched OS/9 works just fine.

hase
-- 
Hartmut Semken, Lupsteiner Weg 67, 1000 Berlin 37 hase@netmbx.UUCP
High on a rocky promontory sat an Electric Monk on a bored horse. (D. Adams)