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From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: DMA Problem?
Message-ID: <1293@lpami.wimsey.bc.ca>
Date: 23 Mar 90 20:49:29 GMT
Lines: 31
Return-Path: <lpami!lphillips>
To: van-bc!rnews

In <106724@pyramid.pyramid.com>, eric@pyramid.pyramid.com (Eric Bergan) writes:
>	I have an Amiga 2000, with an original 2090 controller and a
>Micron 2 Meg board. I seem to be experiencing frequent guru's (all 3's)
>at random intervals, but normally during accesses to my disk drive.
>(Seems to happen equally on reads and writes. Of course, on writes, I
>have to recover the disk..)
>
>	When I pull the 2 Meg board, I don't seem to have the problems.
>Now, first, does anyone know if there are problems between the 2090 and
>the Micron board? Both are probably early rev's. If anyone has heard of
>a problem, is the offending piece the memory board, or the controller?
>
>	If anyone knows a definitive solutions for this (particularly one
>not involving replacing one board or the other), I will be very greatful.

Sounds a lot like a problem I was having, which was a matter of either timing
or loading on the Zorro bus.  I tried adding the pullup resistor to bring my
4.4 motherboard up to 4.6, which did nothing, and replacing all 6 bus drivers,
which helped quite a bit. I ended up replacing the Buster chip, and things are
working well now. This was on a machine with a 2630, 2090A, Micron 8 meg memory
board (2 megs in it), and a HardFrame.

-larry

--
Entomology bugs me.
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|   //   Larry Phillips                                                 |
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