On Fri, May 30, 2014 at 11:09 AM, András Bíró <andras.b...@ucmote.com> wrote:
> Hi, > > Think about what the ADC reading means. It's a 10 bit adc. You have a > maximum amplitude of 14. That's 3*14/4096=0.01V. That's not much, you > probably don't need more precision. > > The reason of this can be faulty measure, yes. The ADC in these MCUs are > usually better than this, but the wiring might get some noise from the > surrounding circuit. However, this might not be a measuring error at all. > The voltage of the battery depends on current and temperature (and > temperature depends on ambient temperature and current). I think 0.1V > oscillation is acceptable. > I meant 0.01V here. > > Andris > > > On Tue, May 27, 2014 at 7:58 PM, Guilherme Politta < > guilhermepoli...@gmail.com> wrote: > >> I did a experiment with a micaz node. x-axis (in hours) is time, y-axis >> is voltage. >> Looks reliable. >> >> >> 2014-05-27 2:32 GMT-03:00 Premkumar Arumugam <psgp...@aol.com>: >> >>> Hello all, >>> >>> I am using TelosB motes, and I used VoltageC to know the battery status. >>> I have plugged the fresh batteries and I was checking the battery status. >>> >>> I used two motes, one mote read the battery status for every one minute >>> and send the read value to another mote which display the ADC count. >>> >>> Initially at the beginning of the experiment, I received the ADC count >>> value of 4096 and it was stable for few readings. >>> Once the experiments ran for few hours, the ADC level was strange. >>> >>> for.e.g >>> >>> 132 minute =4003 >>> 133 minute =4010 >>> 134 minute=4009 >>> 135 minute=3998 >>> 136 minute =4012 >>> >>> The value kept on oscillating. Shouldn't be a decrease/or at-least >>> stable ADC value when motes consumption time increases. >>> >>> I wanted to know, was this type of measuremnt is relaible? do we have >>> any other alternative measurement? >>> >>> Experts, please share your views. >>> >>> Thanks, >>> Prem >>> >>> >>> >>> _______________________________________________ >>> Tinyos-help mailing list >>> Tinyos-help@millennium.berkeley.edu >>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >>> >> >> >> >> -- >> Guilherme Politta >> >> _______________________________________________ >> Tinyos-help mailing list >> Tinyos-help@millennium.berkeley.edu >> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >> > >
_______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
