Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!gatech!uflorida!haven!uvaarpa!virginia!kesmai!dca
From: dca@kesmai.COM (David C. Albrecht)
Newsgroups: comp.sys.amiga
Subject: Re: A2000 DMA SCSI disk controllers: What's the final word?
Message-ID: <217@kesmai.COM>
Date: 2 Jun 89 18:15:50 GMT
References: <2639@shlump.dec.com>
Organization: Kesmai Corporation, Charlottesville, VA
Lines: 34

In article <2639@shlump.dec.com>, kaye@FSCORE.dec.com writes:
> Finally had a friend bring his A2000 + 2090A + 2058 over. Found ECO on the 
> 4.4 motherboard (a resistor on U604). Installed a same resisitor on my machine
> & everything works fine. Called CBM & they confirmed the ECO as required if 
> expansion slots are used. Machine has been solid ever since. 
Could you be more specific please?  I have an A2000 with a rev 4.2
motherboard and a Micron 2M board.  The Micron board and the 2090 have
never played well together.  I can run diagnostics on the Micron board
till I'm blue in the face and they never fail but, just try and use
MRBackup to back the disk up and GURU.  I cranked max transfer down
quite a bit and it makes it better but not perfect.  If this could fix
my problems with the Micron board it would be great.  On my system
U604 is a SN74LS245N, a twenty pin dip, like so:

   Back of A2000
   +---+
1  |o  | 20
2  |   | 19
3  |   | 18
4  |   | 17
5  |   | 16
6  |   | 15
7  |   | 14
8  |   | 13
9  |   | 12
10 |   | 11
   +---+
   Front of A2000

between which pins is the resistor?  what value of resistance is it?

Thanx in advance.

David Albrecht