Calibration

*/
// These constants won’t change:
const int sensorPin = A0;    // pin that the sensor is attached to
const int ledPin = 9;        // pin that the LED is attached to
// variables:
int sensorValue = 0;         // the sensor value
int sensorMin = 1023;        // minimum sensor value
int sensorMax = 0;           // maximum sensor value
void setup() {
  // turn on LED to signal the start of the calibration period:
  pinMode(13, OUTPUT);
  digitalWrite(13, HIGH);
  // calibrate during the first five seconds
  while (millis() < 5000) {
    sensorValue = analogRead(sensorPin);
    // record the maximum sensor value
    if (sensorValue > sensorMax) {
      sensorMax = sensorValue;
    }
    // record the minimum sensor value
    if (sensorValue < sensorMin) {
      sensorMin = sensorValue;
    }
  }
  // signal the end of the calibration period
  digitalWrite(13, LOW);
}
void loop() {
  // read the sensor:
  sensorValue = analogRead(sensorPin);
  // apply the calibration to the sensor reading
  sensorValue = map(sensorValue, sensorMin, sensorMax, 0, 255);
  // in case the sensor value is outside the range seen during calibration
  sensorValue = constrain(sensorValue, 0, 255);
  // fade the LED using the calibrated value:
  analogWrite(ledPin, sensorValue);
}
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One thought on “Calibration

  1. What happen in this situation is when I put my figure on the Light Sensor, the light on the LED will turn off and when I move my figure away from the light sensor, the light on the LED will turn on. The input of this project is the figure touch the light sensor or no and the output of this project is the light on LED turn on or not.

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