The hardware is consists of an Arduino microcontroller (here an Arduino Uno R3) and a pre-wired soil moisture sensor module ... be linked to the little circuit shown below, and use an external 5VDC ...

First of all, note that the circuit ... sensor and converted into a proportional voltage. The output of the ACS712 has a positive slope (>VIOUT(Q)) when an increasing current flows through the primary ...

Instead of using two resistors, [Technoyaki] decides to build an analog circuit ... an Arduino Due, which has a 12-bit A/D converter (almost, because it has a lower reference voltage of 3.3 ...