  * @author "Yusuke Doi"
  * @param msg This param is msg object of the motor_driver topic.
  */
-void steerCb(const geometry_msgs::Twist& msg) {
+void steerCb(const geometry_msgs::Twist& msg)
+{
   int time = msg.angular.x * 10;
   if (msg.angular.z < 0 && time > 50) gen_pluse(LEFT, time); // Minus mean CCW or right.
   else if (msg.angular.z > 0 && time > 50) gen_pluse(RIGHT, time); // Plus mean CW or left.

/* Define pulse width time of the stepping motor. */
#define PULSE_WIDTH_MICRO_SECOND 500

enum {
  LEFT,
  RIGHT,
  KEEP
};

enum {
  cw_plus = 3,
  cw_minus,
  ccw_plus,

ros::NodeHandle nh; // The nodeHandle.
ros::Subscriber<geometry_msgs::Twist> sub("steer_ctrl", &steerCb); // Set subscribe the motor_driver topic.

void setup()
{
  /* Set pins Mode. */
  for (int i = cw_plus; i < ccw_minus + 1; i++)
  { // 3: CW+, 4: CW-, 5: CCW+, 6:CCW-
    pinMode(i, OUTPUT);
    digitalWrite(i, LOW); // Default pin status is LOW.
  }
