Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!oliveb!amiga!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Memory Woes
Message-ID: <8856@cbmvax.UUCP>
Date: 6 Dec 89 20:32:56 GMT
References: <2646@caesar.cs.montana.edu>
Distribution: usa
Organization: Commodore Technology, West Chester, PA
Lines: 30

in article <2646@caesar.cs.montana.edu>, icsu8212@caesar.cs.montana.edu (Stone) says:

> I recently bought a SupraRam 2000 w/2MB ... All the rolling bits tests and 
> They indicate an error in data bit D1 bad bit 00000000  00000010 for both
> boards and every configuration of ram chips in every slot.  Supra
> suggested (after getting the same results with two different boards) that
> I probably have a problem with my Agnes chip.  

I certainly wouldn't suspect Agnus.  She's not in the data path.  If you're
saying that in every single test, every memory location, etc. you're seeing a
D1 high, my first guess would be that you have a rather persistent short on
the D1 line in the expansion bus, possibly directly to +5V.  If you had only
tested one Supra board, I would be real sure that the board itself had this
short.  If you have other expansion devices that work well, I'd start to
suspect Supra's manufacturing, since that would tend to point to two boards
each with the D1 short.  If you have nothing else in the expansion bus, my
guess would that there's a D1 short on your motherboard.  I've never heard of
this happening before, but I suppose there's a first for everything.  Note that
the board would still configure with that short -- autoconfig only uses D15-D8
for most boards.  If you have something like an autoboot hard disk controller
out there, you can be sure there's no short on the bus.  In any case, it 
wouldn't hurt to try a different memory board in the bus, maybe you could just 
borrow one from someone.  Every 2000 is supposed to be tested with memory and
other cards on the production line.

>   ///         Mike Stone        |          Nothing can possibly go wrong.
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
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                    Too much of everything is just enough