> -----Original Message-----
> From: fernteix [SMTP:fernteix@TELEWEB.PT]
> Sent: Friday, May 26, 2000 12:22 PM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Re: usart to usart
>
> Hi
>
>
> <Anyway, the point is, the 877's freak out when I touch
> >the case or RB3 with my finger.  It skips lines of code, things ground
> out.
> >LED's go off.  buzzers go on...   Swap a 774 into the circuit's ZIF, and
> all the
> >flaky stuff goes away.
>
> But more interesting, why the
> >ceramic package itself does this also?
>
> I all this happened in analog world, without reading other details, I
> would
> think in electric field produced by a finger not grounded ! , injecting
> current in high impedance inputs;  and the effect of  humidity lowering
> the
> high impedance of ceramic surface
> Is a possibility only, of course.
>
> Fernando
>
An analog engineer once siad: "all electronics are analog.  Digital stuff is
just analog that's driven too hard"

Mike