Serial.print("010C\r"); // Send the "01 0C" command to the OBD-II adapter // Wait for a response from the OBD-II adapter delay(100); // Wait for 100 milliseconds to allow the OBD-II adapter to respond ...

This Arduino based little digital tachometer was originally created for counting the speed of turntables and fidget spinners. There is another application to consider – a rear wheel tachometer for ...