// the setup funtion runs once when you press reset and or power the board
void setup() {
  //Define Pins
  #define pwm = D7; // PWM on pin D7

  //set pin D7 as an OUTPUT
  pinMode(pmw,OUTPUT);
}

// the loop funtion runs over and over again forever
void loop() {
  //writes the duty cycle with value between 0 and 255
  analogWrite(pmw,50);
  delay(1000);
  analogWrite(pmw,100);
  delay(1000);
  analogWrite(pmw,150);
  delay(1000);
  analogWrite(pmw,200);
  delay(1000);
}