The Soil Moisture Sensor Module (Resistance) consists of two probes that are used to measure the volumetric content of water. The two probes allow the current to pass through and then it gets the resistance value to measure the moisture value. However, the major issue with resistive soil moisture sensors is the corrosion of the sensor probes. it is because it is in contact with the soil while there is also a DC current flowing which causes electrolysis of the sensors.
DO: digital output (0 and 1)
AO: analog output
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