A capacitive soil moisture sensor that is able to measure changing capacitance caused by fluctuating moisture was developed by David, who wanted to create a solution to the problem of corrosion which occurs when conventional resistive moisture sensors come into direct contact with moist conditions.
The device incorporates an STM32 microcontroller and a small seven-segment e-ink display, both of which are optimised for low-power applications.
The microcontroller only wakes up every 15 minutes to take a measurement and update the display, which shows the gradients of varying types of measurement data.
The contrast of the display can be increased or decreased at any time, but the display will only remain legible for approximately 10-15 minutes before requiring another update.
