Re: Another Zip story, episode 2...

[o9938156@wsuaix.csc.wsu.edu (mark lyon)]

bazyar@netcom.com (Jawaid Bazyar) writes:
: o9938156@wsuaix.csc.wsu.edu (mark lyon) writes:
: 
: >I then tried just a single sheet of aluminum foil, attached to
: >the back of the board with double-stick tape.  This gave the
: >best results yet (fewest crashes), but the computer would
: >still crash after a while.  Other than that, I don't know
: >how to increase the capacitance further, without finding
: >the offending lines & attaching capacitors to them.  
: 
:   That's a bad idea, since you _want_ motion on data and address
: lines (well, from 0->5 V). Small (.01uF) caps might help here,
: but would really clutter up the board.

I agree.  This would only work if the noise is a couple orders
of magnitude faster than the signals we want, which I doubt,
because if the noise is interference between lines, then
it would be of roughly the same frequency as the signal we
want in the line :(  If I get time, I'll take the GS into
the lab and look with a 'scope, but I'm not too optimistic.
: 
:   It is beginning to look like only low-power SRAMs will do the
: trick on a Zip.. but I'd still like to know why.

I've heard of people having the same sorts of problems with
LP SRAM's, but at 20 MHz!

Mark.

: 
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