void setup() { // initialize serial communications (for debugging only): Serial.begin(9600); } void loop() { // read the sensor: int sensorReading = analogRead(A0); // print the sensor reading so you know its range Serial.println(sensorReading); // map the analog input range (in this case, 400 - 1000 from the photoresistor) // to the output pitch range (120 - 1500Hz) // change the minimum and maximum input numbers below // depending on the range your sensor's giving: int thisPitch = map(sensorReading, 400, 518, 120, 1500); // play the pitch: tone(3, thisPitch, 1000); delay(100); // delay in between reads for stability }