void setup() {
  // put your setup code here, to run once:
#define LED_PIN 11
  pinMode(LED_PIN, OUTPUT);
  analogWrite(LED_PIN, 102);
}


void loop() {
  // put your main code here, to run repeatedly:

 for (int i = 0; i <= 255; i++) {
    analogWrite(LED_PIN, i);
    delay(1);
  }
  
  for (int i = 255; i >= 0; i--) {
    analogWrite(LED_PIN, i);
    delay(1);
  }

}