//Nome: Estrela José Marcolino
 
 #define DIR  19
 #define STEP 20
 #define PUSH 28

void setup() {
 pinMode(DIR, OUTPUT);
 pinMode(STEP, OUTPUT);
 pinMode(PUSH, INPUT_PULLUP);
}

void loop(){
  digitalWrite(DIR, LOW);
  if(digitalRead(PUSH)==0)
     digitalWrite(STEP, HIGH);
  else
    digitalWrite(STEP, LOW);
  delay(1);
}