Re: [avr-gcc-list] Best practice for external variable (newbie-ish question)

[Matthew Smith]

Hi

> Behaves with potentiometer but not with real sensor? Then I suggest 
> studying the analog input circuit from the sensor and consider adding 
> filtering.
Sorry - wasn't making myself clear there.  It misbehaves with the pot,
but I can't check with the real sensor as I have no way of generating
enough pressure.  (Blowing in it nearly gave me a hernia just trying to
get a reading; it's a 7 bar sensor...)  I can check the input voltage
with a multimeter anyway.

I'm actually working on a mean value of five samples (or at least the
mean cast as an integer ;-)) to remove glitches.  Haven't got the code
in front of me, but think it's something like the mean reading over 100ms.

I believe that the analogue side is OK - if I use (simulated) pressure
only (timer is not brought into play), it seems to behave, although I'll
do some more thorough testing on that.

Thanks for the debug suggestions - I'll keep those to one side as I may
well be needing them later...

Cheers

M

-- 
Matthew Smith
Work: <http://www.kbc.net.au> | Home: <http://www.mss.cx>

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