RPM this is an RPM Measuring using Arduino by Arduino Timers first u need to install timer.h library you can download from this link https://github.com/brunocalou/Timer Second one for STM32 + OLED 0.96 and use these libraries for this one https://github.com/adafruit/Adafruit_SSD1306 https://github.com/adafruit/Adafruit-GFX-Library