#ifndef Car_Lib_h
#define Car_Lib_h

float ultrasonic_distance(int trigPin, int echoPin);
int potentiometer_Read(int pin);

void motor_forward(int IN1, int IN2, int speed);
void motor_backward(int IN1, int IN2, int speed);
void motor_hold(int IN1, int IN2);


#endif
//car.library.cpp  부분
#include "Arduino.h"

float ultrasonic_distance(int trigPin, int echoPin)
{
    long distance, duration;

    digitalWrite(trigPin, LOW);
    digitalWrite(echoPin, LOW);
    delayMicroseconds(2);

    digitalWrite(trigPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(trigPin, LOW);
    duration = pulseIn(echoPin, HIGH);
    distance = ((float)(340 * duration) / 1000) / 2;

    return distance;
}

int potentiometer_Read(int pin)
{
    int value;

    value = analogRead(pin) / 4; //analogRead(pin)/4의 이유: 
    //analogRead(pin)은 0~1000 범위 하지만 pwm은 0~255까지의 값밖에 못읽기 때문에 /4를 해줌.
    //value = map(value,0,1000,0,255) 이런식으로 바꿔도 좋음

    return value;
}

void motor_forward(int IN1, int IN2, int speed)
{
    analogWrite(IN1, speed); //IN1은 speed 출력 
    analogWrite(IN2, LOW); //IN2는 LOW 출력 = 정방향 회전
}

void motor_backward(int IN1, int IN2, int speed)
{
    analogWrite(IN1, LOW); //IN1은 LOW 출력 
    analogWrite(IN2, speed); //IN2는 speed 출력 = 역방향 회전
}

void motor_hold(int IN1, int IN2)
{
    analogWrite(IN1, LOW);
    analogWrite(IN2, LOW); //IN1,2 모두 LOW는 정지
}

int trig=3;
int echo=2;
long distance;
int analogPin = A5;
int val;
int motorA1=4;
int motorA2=5;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(motorA1, OUTPUT);
  pinMode(motorA2, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:

//  distance=ultrasonic_distance(trig,echo);
//  Serial.print(distance);
//  Serial.println(" mm");
  
  val=potentiometer_Read(analogPin);
  Serial.println(val);
// 개조한 코드
  if(val <= 50)
  {
    motor_hold(motorA1,motorA2);
  }
  else
  motor_backward(motorA1,motorA2,175);
  //개조한 코드 

 /* motor_forward(motorA1,motorA2,val);*/
 //원래 코드
}