//L293D
//Motor A (left)
const int motorPin1  = 9;  // Pin 2 of L293
const int motorPin2  = 10;  // Pin 7 of L293
//Motor B (right)
const int motorPin3  = 11; // Pin  10 of L293
const int motorPin4  = 12;  // Pin  15 of L293

#define TIME_WAIT 7200 //10sec

void setup() {
  //Set pins as outputs
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
  pinMode(motorPin3, OUTPUT);
  pinMode(motorPin4, OUTPUT);
}

void motor_a_stop() {
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, LOW);
}

void motor_a_forward() {
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, HIGH);
}

void motor_a_backward() {
  digitalWrite(motorPin1, HIGH);
  digitalWrite(motorPin2, LOW);
}

void motor_b_stop() {
  digitalWrite(motorPin3, LOW);
  digitalWrite(motorPin4, LOW);
}

void motor_b_forward() {
  digitalWrite(motorPin3, LOW);
  digitalWrite(motorPin4, HIGH);
}

void motor_b_backward() {
  digitalWrite(motorPin3, HIGH);
  digitalWrite(motorPin4, LOW);
}

void left_stop() {
  motor_a_stop();
}

void right_stop() {
  motor_b_stop();
}

void stop() {
  left_stop();
  right_stop();
}

void left_forward() {
  motor_a_backward();
}

void left_backward() {
  motor_a_forward();
}

void right_forward() {
  motor_b_forward();
}

void right_backward() {
  motor_b_backward();
}

void forward() {
  left_forward();
  right_forward();
}

void backward() {
  left_backward();
  right_backward();
}

void left_rotate() {
  left_backward();
  right_forward();
}

void right_rotate() {
  left_forward();
  right_backward();
}

void left_circle() {
  left_stop();
  right_forward();
}

void right_circle() {
  right_stop();
  left_forward();
}

void wait() {
  delay(TIME_WAIT);
  stop();
}

void loop() {
  forward();
  wait();
  backward();
  wait();
  left_rotate();
  wait();
  right_rotate();
  wait();
  left_circle();
  wait();
  right_circle();
  wait();
  stop();
  delay(1800);
}