#include <Stepper.h>

const int stepsPerRevolution = 200;

Stepper s(stepsPerRevolution, 8,9,10,11);

void setup() {
  s.setSpeed(60);
}

void loop() {
  s.step(stepsPerRevolution);
  delay(0);

  s.step(-stepsPerRevolution);
  delay(0);
}