> industrial
> envoiroment,which means it is subject to be bothered by line
> noises.Hence,I thought the WDT might be the solution for
> that.

Some other folks will probably post about how to implement WDT.  I
don't think, though, that a WDT will help much in a noisy
environment.  Watchdog timer will mostly protect you against software
loops hanging, perhaps waiting for an input.  If your power is flaky,
your processor might not even RUN, and the watchdog will be useless.

In a noisy environment, I use two things - heavily filtered power
supply, and brownout protection.  Some of the newer PICS have
built-in brownout circuits.  Use 'em.   Then make sure your power
supply is really clean.  Use all the normal tricks to prevent hash
from coming in through your peripherals such as analog inputs,
potentiomenters, etc.


-- Lawrence Lile

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