#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define SOUND_SPEED 0.034
#define TIMEOUT 30000 

const int trigPinL = 2;
const int echoPinL = 3;

const int trigPinR = 7;
const int echoPinR = 8;  

long durationL, durationR;
float distanceCmL, distanceCmR;

LiquidCrystal_I2C lcd(0x27, 16, 2); 

void setup() {
  Serial.begin(115200); 
  pinMode(trigPinL, OUTPUT);
  pinMode(echoPinL, INPUT);
  pinMode(trigPinR, OUTPUT);
  pinMode(echoPinR, INPUT);
  lcd.init();       // initialize the LCD
  lcd.clear();      // clear the LCD display
  lcd.backlight();  // Make sure backlight is on
  lcd.setCursor(0, 0);
  lcd.print("Starting...");
  lcd.clear();
  delay(1000);

}

void loop() {
 
  digitalWrite(trigPinL, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPinL, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPinL, LOW);

  durationL = pulseIn(echoPinL, HIGH, TIMEOUT);
  distanceCmL = (durationL > 0) ? (durationL * SOUND_SPEED / 2) : -1;  

  delay(50);

  digitalWrite(trigPinR, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPinR, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPinR, LOW);

  durationR = pulseIn(echoPinR, HIGH, TIMEOUT);
  distanceCmR = (durationR > 0) ? (durationR * SOUND_SPEED / 2) : -1;

  Serial.println("Distance (cm):");
  Serial.print("Right: ");
  Serial.println(distanceCmR);
  Serial.print("Left: ");
  Serial.println(distanceCmL);

char buffer[7]; 

lcd.setCursor(0, 0);
lcd.print("L:");
dtostrf(distanceCmL, 6, 2, buffer); 
lcd.setCursor(3, 0);
lcd.print(buffer);
lcd.setCursor(10, 0);
lcd.print("cm");

lcd.setCursor(0, 1);
lcd.print("R:");
dtostrf(distanceCmR, 6, 2, buffer);
lcd.setCursor(3, 1);
lcd.print(buffer);
lcd.setCursor(10, 1);
lcd.print("cm");


  delay(200);

}