code: function start()
  {
      if (motor)
      {
          // configure it, for this example, we'll assume 200 steps per rev
          motor.configStepper(200);
          motor.setStepperSteps(100);
          // start it going at 10 RPM
          motor.enableStepper(mdObj.MD.STEP_DIR_CW, 10);
      }
  }
docs: This example demonstrates using the MD to drive a stepper motor