Project 1 - Interfacing a 16*2 LCD with Arduino using I2C protocol

Embedded c - Offline batch 2 - Kirubhakaran

//master code
#include  //library for I2C protocol
#include  //library for LCD display

LiquidCrystal lcd(12, 11, 2, 3, 4, 5);//initialize the LCD

byte x=0;//global variable declaration

void setup()
{
  lcd.begin(16, 2);
  //to begin the LCD display
  lcd.print("Master Arduino");
  //to denote the master in lcd
  delay(2000);
  lcd.clear();
  
  Wire.begin();
  //to begin the I2C Comunication from master
}

void loop()
{
  Wire.requestFrom(1, 1);
  //to request data from slave
    x=Wire.read();
  	//to read data from the slave
  
  	Wire.beginTransmission(1);//to send data to the slave
  	float temp = analogRead(A0);
  	byte tmp = map(temp,0,1023,0,127);
      Wire.write(tmp);
  	Wire.endTransmission();//to stop transmitting data to slave
  	
    lcd.setCursor(0, 0);
  	//set cursor in first column first row
  	lcd.print("data frm slave");
  	//to print in the LCD display
  	lcd.setCursor(0, 1);
  	//set cursor in first column second row
  	lcd.print(x);
  	//to print the data from slave 
  delay(500);
  	lcd.clear();
  	//to clear the LCD screen  	
}

//slave code

#include //library for I2C protocol
#include //library for LCD display

LiquidCrystal lcd(12, 11, 2, 3, 4, 5);//initialize the LCD

byte y=0;//global variable declaration

void setup()
{
  lcd.begin(16, 2);
  //to begin the LCD display
  lcd.print("Slave Arduino");
  //to denote the slave in LCD
  delay(2000);
  lcd.clear();
  Wire.begin(1);
  //to begin the I2C Comunication from slave
  Wire.onRequest(rqst);//to send data to master when called
  Wire.onReceive(rcv);//to recieve data from master when given
}

void loop()
{
    lcd.setCursor(0, 0);
  	//set cursor in first column first row
  	lcd.print("data frm master");
  	//to print in the LCD display
  	lcd.setCursor(0, 1);
  	//set cursor in first column second row
  	lcd.print(y);
  	//to print the data from master
  delay(500);
  	lcd.clear();
  	//to clear the LCD screen
}

void rcv(int value)
{
  y=Wire.read();
}//to receive data from the master

void rqst()
{
 	float temp = analogRead(A0);
  	byte tmp = map(temp,0,1023,0,127);
      Wire.write(tmp);
  //to write the data to the masters call.
}