Path: utzoo!attcan!uunet!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!cunews!bnrgate!bwdls56!fortinp
From: fortinp@bwdls56.bnr.ca (Pierre Fortin)
Newsgroups: comp.sys.atari.st.tech
Subject: Re: Upgrading Mega 2 to 4.
Summary: Works fine for me...
Message-ID: <1990Oct2.192928.8948@bnrgate.bnr.ca>
Date: 2 Oct 90 19:29:28 GMT
References: <1599@kielo.uta.fi>
Sender: news@bnrgate.bnr.ca (USENET News System)
Organization: Bell-Northern Research, Ltd. Ottawa Ontario CANADA
Lines: 34

In article <1599@kielo.uta.fi>, jackin@vehka.uta.fi (Markku M{enp{{) writes:
> I have a Mega ST 2 which I am planning to update to 4 MB.
> 
> I have now 16 empty sockets available, but putting 80ns
> chips didn't work. It was quite expectable original chips
> being 150ns.

I installed 70ns chips which run just fine.

> 
> Do 120ns chips work or do I need 150ns (rare in 1MB chips) ?
> Is there anything else to do apart putting chips in and 
> soldering capasitators (as is done in original 2 MB) ?

YES!!  You need to add 3 resistors (33 ohm) in the area surrounded by the
existing RAMs, ROMs and the boards edge; somewhere around R61 if I remember
correctly.  There are at least 3 missing resistors there...
> 
> I wanna see my Spectre work with 4MB !!!!
> 
> Thanks,
> Markku
> 
> --
> Markku M{enp{{ 
> email : jackin@vehka.uta.fi
> phone : 358 31 561 575 (in Finland (931) 561 575)

Cheers,
Pierre
Pierre Fortin       Bell-Northern Research     I know, my postings are
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