Al, With my old Semiconductor Company (ahem) we noticed an odd behaviour of inputs that didn't have enough filtering on them. Basically a ESD zap, or a low ground bounce would cause the registers to "loose their data". Solution was to add additional filtering. The 1000pf cap may cause other issues, but a simple 100 to 1K ohm series resistor with a smaller cap is enough to filter to prevent the issue. Worst time it ever appeared was at SAE Convergence! We had metal topped (stainless steel) display tables. Carpet was a huge static generator. Anyone someone shuffled across the carpet, and touched the ungrounded table top all the displays would reset. Mad dash to the store for fabric softener resolved the issue. That and I no longer attached standoffs to the ground plane. :) Tom From: "Al Gietzen" <ALVentures@cox.net> Subject: RE: [FlyRotary] Re: EC2 question Date: Thu, 10 May 2007 14:39:57 -0800 On Thu, 10 May 2007 09:31:30 -0800 "Al Gietzen" wrote:
>
> BTW; preliminary results indicate that the issue I've had with the
> spontaneous changes of settings has been resolved.
> Al
>
What was causing it?
Bob W.
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Don't know exactly. Added additional filtering on the circuit board :
1000pf capacitors were added to:
All fuel injector signals
All ignition control signals
RX input
TX output
47uf, 16V tantalum were added to each processor
Pin 8 of connector is now grounded.
Pin 28 of connector is now grounded.
Al
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