[Tinyos-help] MSP430 ADC first reading

[Dimas Abreu Dutra]

Eric,

I'm not positive it isn't the hardware, but I am POSITIVE I have the voltage
that should return around 0x0916 adc counts. I also have run this on two
different motes (both invent) and noticed the same thing on adaptations that
Urs Hunkeler did of the original tmote invent drivers.

It can be some hardware feature (capacitor transients, etc) but if it was,
the ADC drivers should start it on the boot sequence, so the first readings
would not be erroneous. I can solve this on my own, with a dummy reading
just to clear that, but it wouldn't be a very elegant solution and this can
be a problem to more people on the future. I did read some of the msp430
datasheet, but there is too much detail and complicated state machines, and
the code of the msp adc modules are very complicated too. I can inspect
more, but I think that maybe it should be clearer for people who had more
hands-on contact with the adc.

~Dimas~

On Wed, Jun 18, 2008 at 1:55 PM, Eric Keller <eekeller at psu.edu> wrote:

> Are you positive it isn't hardware?  What version of TinyOS are you
> running?
> Eric
>
>
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