title: Arduino stepper
body: <p>I am building a system with the <a href="http://arduino.cc/en/Main/ArduinoBoardUno" rel="noreferrer">Arduino Uno</a>, a power shield (<a href="http://www.dfrobot.com/wiki/index.php?title=Arduino_Motor_Shield_%28L298N%29_%28SKU:DRI0009%29" rel="noreferrer">REf to model</a>) and a bipolar stepper motor.</p>
  
  <p>I cannot initiate the motor using the stepper library from Arduino. I instantiate my stepper with</p>
  
  <pre><code>Stepper myStepper(motorSteps, motorPin1,motorPin2m motorPin3,motorPin4);
  </code></pre>
  
  <p>And keep on with the example code provided with the Arduino.</p>
  
  <p>When I launch the code on the Arduino, the motor emits some sounds, but it does not turn.</p>
  
  <p>How can determine the right motor pins to use? On the power shield, which mode is to be used, <a href="http://en.wikipedia.org/wiki/Pulse-width_modulation" rel="noreferrer">PWM</a> or <a href="http://en.wikipedia.org/wiki/Phase-locked_loop" rel="noreferrer">PLL</a>?</p>