#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd (0x27, 16, 2);

#define ECHO_PIN 3
#define TRIG_PIN 2
#define pinBuzzer 5

#include <Servo.h>

byte LED = 12;
Servo myservo;
int rotasi = 90;
int interval = 0;

float readDistanceCM(){
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int duration = pulseIn(ECHO_PIN, HIGH);
  return duration * 0.034/2;
}

void soundBuzzerLed(){
  lcd.setCursor(0,0);
  lcd.print("Servo Diturunkan");
  digitalWrite(LED, HIGH);
  if(interval < 500){
    tone(pinBuzzer, 400);
  }else
  digitalWrite(LED, LOW);
  if(interval > 500){
    tone(pinBuzzer, 500);
  };

}

void setup(){
  lcd.begin(12,2);
  pinMode(LED, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  Serial.begin(115200);
  pinMode(pinBuzzer, OUTPUT);
  myservo.attach(9);
  myservo.write(90);
}

void loop(){
  tutupPalang();
  interval +=100;
  if(interval>1000) interval = 0;
}

void tutupPalang(){
  float jarak = readDistanceCM();
  if(jarak > 0 && jarak < 100 ){
    soundBuzzerLed();
    tutup();
  }else{
    buka();
    noTone(pinBuzzer);
  }
}

void tutup(){    
  if(rotasi <= 90){
    myservo.write(rotasi);
    delay(100);
    rotasi--;
  }
  if(rotasi <= 0 ) rotasi = 0;

}

void buka(){
  if(rotasi <= 90){
    myservo.write(rotasi);
    delay(100);
    rotasi+=4;
  }
  if(rotasi >= 90 ) rotasi = 90;
}