Soil Moisture Sensor

Hi all, I’m trying to use a Soil moisture sensor with a Samr21-xpro and RIOT os. The sensor used is as follows :

I have 4 soil jars (with different moisture concentrations) that i’m gonna use for testing, i’ve already tried to get moisture values with Arduino Uno and they seem to be acceptable. For both, i used the built in ADC with 10 bits of resolution.

But when i try to use the samr21, it gets me always 330 as value (10 bits ADC). For the SAMR21 i used the default parameters for ADC_0.

There is a way to rectify the readings, or some kind of calibration to do?

Thanks a lot,

Hi Alessandro,

what are the default values for ADC_0 on the samr21-xpro board and which driver did you use?

Best Peter

Start with measuring the voltage value? Try giving some different analog input less than 3.3V