Hi Bill,

On Mon, May 29, 2006 at 05:29:43PM -0700, William Chops Westfield wrote:
> 
> I'm assuming that most of my problems are due to the bouncy nature
> of power-on in this circuit (cheap switch or cheaper battery clip.)
> The 12f675 has several robustness features (brown out detect, power
> on timer, watchdog), all of which I have turned off at the moment,
> under the assumption that the basic internal reset would be sufficient.
> Apparently not.  What sort of configuration settings and/or external
> circuitry do people find useful or necessary to ensure clean startup
> in battery-powered circuits subject to messy poweron?

I can't say this with absolute certainty, but I would bet that if you enable
the power on reset feature that you problem may be solved. My last battery
powered circuit uses a 12f629 with POR and I've not had any power-up
problems. Inserting batteries or connecting a battery connector is an
operation that is going to bounce just as a switch would.

I can't think of any reason to not use POR in your situation. A change to
the config word will be all that you need to make and your problem may be
solved.

Take care.

Matthew

-- 
8)   Use common sense in routing cable.  Avoid wrapping coax around sources of
     strong electric or magnetic fields.  Do not wrap the cable around
     flourescent light ballasts or cyclotrons, for example.
-- Ethernet Headstart Product, Information and Installation Guide,
   Bell Technologies, pg. 11
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