One possibility is that the ADC needs a certain settling/sampling time prior to each conversion and after channel changes. Perhaps the timing is off the first time around...
MS Dimas Abreu Dutra wrote: > 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 <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> wrote: > > Are you positive it isn't hardware? What version of TinyOS are you > running? > Eric > > > > ------------------------------------------------------------------------ > > _______________________________________________ > Tinyos-help mailing list > [email protected] > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
