int grados = 0, step = 0;
int IN1 = 33;
int IN2 = 23;
int IN3 = 18;
int IN4 = 15;
int del = 5;
int cont = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);
  pinMode(IN3, OUTPUT);
  pinMode(IN4, OUTPUT);

}

void loop(){
  grados = 250;
  step = 0.0;
  int r1 =0, g1 = 255, b1 =0;
  for(int i=0; i<512; i++){
    digitalWrite(IN1, LOW);
    digitalWrite(IN2, LOW);
    digitalWrite(IN3, LOW);
    digitalWrite(IN4, HIGH);
    delay(del);
    //PULSO 2
    digitalWrite(IN1, LOW);
    digitalWrite(IN2, LOW);
    digitalWrite(IN3, HIGH);
    digitalWrite(IN4, LOW);
    delay(del);
    //PULSO 3
    digitalWrite(IN1, LOW);
    digitalWrite(IN2, HIGH);
    digitalWrite(IN3, LOW);
    digitalWrite(IN4, LOW);
    delay(del);
    //PULSO 4
    digitalWrite(IN1, HIGH);
    digitalWrite(IN2, LOW);
    digitalWrite(IN3, LOW);
    digitalWrite(IN4, LOW);
    delay(del);
    step = step + 1;
  }
}