Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!haven!umd5!matthews
From: matthews@umd5.umd.edu (Mike Matthews)
Newsgroups: comp.sys.atari.st
Subject: Re: help with DEAD atari
Message-ID: <6174@umd5.umd.edu>
Date: 26 Feb 90 23:49:51 GMT
References: <5429@crdgw1.crd.ge.com> <1990Feb22.171852.1512@ns.network.com>
Reply-To: matthews@umd5.umd.edu (Mike Matthews)
Organization: University of Maryland, College Park
Lines: 27

In article <1990Feb22.171852.1512@ns.network.com> logajan@ns.network.com (John Logajan) writes:
[stuff deleted]
>However, later versions of the 520ST and none of the 1040's and
>Mega's have Sam's for them.  I guess Atari decided to keep it
>all secret.  Still, except for blitters, etc, the general chip
>set is the same (I presume) so the 520ST schematics might be
>a good starting off point for other versions.
>
Actually, Atari really diversified with chips.  I've seen several different	DMA chips and floppy controllers (anybody else have a VLSI1772 FC, as opposed
to the "standard" WD1772?).  All the chips are not 100% compatible, either...
Actually, I can't say that with 100% certainty.  My first DMA chip refused to
work with Spectre 128/ICD/Seagate 251/Adaptec 4000, but worked fine with every-
thing else.  The "new" DMA chip (actually an older model) worked fine with that
setup, but *something* is mighty unhappy when I try to use a Seagate 296N with
an ICD host adaptor and a Conner CP340 with a BMS200 HA online at the same
time. (yes, the SCSI IDs are not the same)

There are also four? versions of the blitter chip.

Plus, there's this new talk of SIMMs or SIPPs (SIPs?), depending on which is
cheaper...
>
>-- 
>- John Logajan @ Network Systems; 7600 Boone Ave; Brooklyn Park, MN 55428
>- logajan@ns.network.com, john@logajan.mn.org, 612-424-4888, Fax 424-2853

Mike