I'm not sure what you mean by "engineering units",
but if you have "ADC counts" they are the raw data
from the converter. These are exactly equivalent
to voltage, since that is what is being converted:
volts = count/MAX * Vref
Where:
volts is the signal voltage;
count is the "ADC counts" result you have;
MAX is the ADC maximum range (10 bits == 1024 for the atmega);
Vref is the ADC reference voltage (nominally 3.3v for most)
For acoustic data, from a microphone, what you are getting
is the instantaneous signal voltage when the sample is made.
This will vary over the entire range of the ADC since you are
sampling a fast changing AC signal, usually at a very slow rate.
MS
Omar Bouzid wrote:
> Hi All,
>
> By looking to the displayed data in MoteView most of them are displayed
> in engineering units which are unlikely to give any sense, in
> particularly the acoustic data that are captured by mts310's microphone.
> Thus, I would like to know if someone have any experience to convert
> them to voltage units.
>
> Cheers, OMB
>
>
> _______________________________________________ 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
