Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!wasatch!uplherc!esunix!blgardne
From: blgardne@esunix.UUCP (Blaine Gardner)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Expansion boxes vs 2000 slots
Message-ID: <1427@esunix.UUCP>
Date: 7 Aug 89 14:19:49 GMT
References: <18498@gryphon.COM>
Organization: Evans & Sutherland Computer Corporation
Lines: 41

From article <18498@gryphon.COM>, by rickf@pnet02.gryphon.com (Rick Flower):
> Well, I've had a few people send me messages (you I'm sure know who you are
> (:-) ) about the pals possibly needing to be grounded to make the ToolBox work
> better, and I just wanted to add that they ARE grounded and that didn't help
> much at all.. I'm in the process of having the PAL's completely replaced and
> I will see if that helps at all (I'm suspecting that it won't!).  I must say
> that I'm not too impressed with these "ToolBox" types of hardware...

One more thing to try is swapping the 68000 if it is not a Motorola
part. 

I've had an ASDG Minirack C (unbuffered parital Zorro I box) with a 2M
RAM card on my 1000 for over two years without any problems. Then last
month I added a Spirit Tech. clock (similar design to the Spirit
internal RAM board, but just the clock) and the system became completely
unreliable. It would crash anywhere from Kickstart, all the way up to
running a random application. 

I was ready to toss the clock board in the trashcan, but I gave Spirit a
call, and after hearing my tale of woe, they told me to come down so
they could take a look at my system. They suggested the PAL grounding,
but I'd already done that with no effect. Their next step was to replace
the original Hitachi 68000 with a 10 MHz Motorola part. Surprise! The
crashes went away completely.

The Spirit tech didn't have any good explanation of why the Motorola
part fixed everything, just the observation that they'd had this "fix"
work a number of times in the past. My own guess is that the Hitachi and
Signetics (also supposed to have the same problem) 68000's don't provide
the same kind of fan-out that the Motorola 68000 does.

Now this is obviously a hack and a kludge, not a real solution to the
problem, on the other hand, if it works, it's hard to argue with it. I
was pretty leery of this fix, but I've tried everything I can to crash
the system, and it is still stable. Swapping the CPU will be easier than
swapping the PALs, so you might want to try it first.
-- 
Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
Here: utah-cs!esunix!blgardne   {ucbvax,allegra,decvax}!decwrl!esunix!blgardne
There: uunet!iconsys!caeco!i-core!worsel!blaine  (My Amiga running uucp)
"Nobody will ever need more than 64K."    "Nobody needs multitasking on a PC."