I’m waiting for some more parts to build my bike computer so I figured I should play around with the parts I got with my Arduino. Here I used a potentiometer to control some LEDs. The output from the pot is connected to an analog pin, and each LED is hooked up to a digital pin. Code: int sensorPin = A0; // select the input pin for the potentiometer int sensorValue = 0; // variable to store the value coming from the sensor int mappedValue = 0; void setup() { // declare the LED pins as OUTPUTs: pinMode(2, OUTPUT); pinMode(3, OUTPUT); pinMode(4, OUTPUT); pinMode(5, OUTPUT); Serial.begin(9600); //for testing } void loop() { // read the value from the sensor: sensorValue = analogRead(sensorPin); // map the sensor range (0-1023) to the number of LEDs (4, plus one for off) mappedValue = map(sensorValue, 0, 1023, 0, 4); // for testing Serial.println(sensorValue); Serial.println(mapped); // loop through all of the pins for(int i = 0; i <= 4; i++){ // if a pin is within the mapped sensor value, turn it on if(i < mappedValue){ // +2 because pins 0 and 1 are for serial I/O digitalWrite(i+2, HIGH); // if a pin is outside sensor value, turn it off } else { digitalWrite(i+2, LOW); } } }