Although it is somewhat of a nuisance to buy (because it is not available in many internet stores), I find it necessary to discuss STM32 L432KC. This chip deserves special affection, as it is ULTRA LOW POWER. However, for those who do not own the STM32, it can be replaced in this project by the Arduino Uno. To do this, simply change the pin of the Interrupt input.
Let’s then create an RPM meter using the STM32 L432KC and an infrared sensor. This same program can also be used to measure wind speed. The low-power feature of this microcontroller is perfect for IOT.”