void setup() {
  // put your setup code here, to run once:
pinMode(9,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
for(int a=0;a<=255;a++)
{
analogWrite(9,a);
Serial.println(a);
delay(10);
}
for(int a=255;a>=0;a--)
{
  analogWrite(9,a);
  Serial.println(a);
Serial.println(a);
}
}