const int redPin = 11;
const int bluePin = 10;
const int greenPin = 9;

int val;

void setup() {
   pinMode(redPin, OUTPUT);
   pinMode(bluePin, OUTPUT);
   pinMode(greenPin, OUTPUT);
   Serial.begin(9600);
}

void loop() {
   for (val = 255; val> 0; val--) {
      analogWrite(11, val);
      analogWrite(10, 255 - val);
      analogWrite(9, 128 - val);

      Serial.println(val, DEC);
      delay(5);
   }
   for (val = 0; val <255; val ++) {
      analogWrite(11, val);
      analogWrite(10, 255 - val);
      analogWrite(9, 128 - val);

      Serial.println(val, DEC);
      delay(5);
   }
}