Project 2 - Measuring the distance of an object using ultrasonic sensor and also smoothen the sensor data using moving average filter

//MASTER
#include<LiquidCrystal.h> // Header to use LCD functions
#include<Wire.h> // Header to use I2C communication
LiquidCrystal lcd(2,3,4,5,6,7); //pins connected to LCD
int distance; //variable to print the data from slave

void setup()
{
Serial.begin(9600);
Wire.begin(); //To begin I2C communication
lcd.begin(16,2); //To begin LCD display
}

void loop()
{
Wire.requestFrom(8,4); // 8 is address 4 byte
distance=Wire.read(); //To print character by character
lcd.setCursor(0,0); //set position of lcd cursor
lcd.print(distance); //To print the received message from slave 1
lcd.print(" inches"); //To display in LCD
delay(50); //delay
Wire.end(); //To end the I2C transmission
}

//Slave
#include<Wire.h> // Header to use I2C communication

int sig = 2; //Assigning pin2 as sig
int duration, inches, cm; //Declaring as integer type
int avg; //Declaring avg as int type

void setup()
{
Serial.begin(9600);
pinMode(sig,OUTPUT);
Wire.begin(8); //To begin I2C communication with address 8
Wire.onRequest(distance); //Calling function from master
}

void loop()
{
delay(100);
}

void distance()
{
pinMode(sig, OUTPUT); //Declaring pin2 as output
digitalWrite(sig, LOW); //Sensor is triggered by pin2 with delay
delay(5);
digitalWrite(sig, HIGH);
delay(10);
digitalWrite(sig, LOW);

pinMode(sig, INPUT); //Declaring pin2 as input
duration = pulseIn(sig, HIGH); //To read the pulse

inches = (duration/74)/2; //converting time into a distance
Wire.write(inches); //Return value to master
delay(10);
}