int led = 9;
int brightness = 255; // run 1 time in code
int d = 1000;
void setup() {
  pinMode(led,OUTPUT);


}

void loop() {
  brightness = 255;
  analogWrite(led,brightness);
  delay(d);
  brightness = 127;
  analogWrite(led,brightness);  
  delay(d);
  brightness = 64;
  analogWrite(led,brightness);  
  delay(d);
 
}