Hi, Lawrence


> "Crazy" is so far the best technical term I have to describe this
> phenomenon.  On the same line of thinking that you are using, I could
> arrange a circuit that would keep it in reset for a long time on power up
> until things got more stable....?
>
> --Lawrence

    Not really :-( It maybe a hardware problem with some sort of "small
latchup" or something like that. Please keep in mind that it is just an
"hyphotesis". You may try to keep reset longer and that will show you one of
the possible problems, but it is not a substitute for a different and clean
power supply. You would be testing 2 different possibilities. If you have no
possibility of a software glitch you will have to make tests and eliminate
the possible problems. Some of the problems that come to mind are:

    Brownout with reset problems. Keep the reset on for a longer time.
    Latch-up somewhere in the chip. The clean supply would at least make
sure that it is not coming from the supply lines.
    Temperature problems. Easy to test, take the board away from the heat.
    Noise induced from the input and output lines. That is a hard one to
debug ! Let's hope it is not the case. Anyway put some varistors on the
lines and see if it gets any better.

Best regards,
Alexandre Guimaraes

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