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

#include    //Library for I2C Communication functions
#include    //Library for LCD display function
LiquidCrystal lcd(2, 7, 8, 9, 10, 11);

//Define LCD Module Pins (RS,EN,D4,D5,D6,D7)

void setup()

{
lcd.begin(16,2);

//Initilize LCD display

lcd.setCursor(0,0);

//Sets Cursor at first line of Display
lcd.print("CYIENT");

//Prints CIRCUIT DIGEST in LCD
lcd.setCursor(0,1);

//Sets Cursor at second line of Display
lcd.print("I2C MASTER ARDUINO");

//Prints I2C ARDUINO in LCD
delay(5000);                               

 //Delay for 5 seconds
lcd.clear();

//Clears LCD display
Serial.begin(9600);

//Begins Serial Communication at 9600 baud rate
Wire.begin();

//Begins I2C communication at pin (A4,A5)
}

void loop()

{
Wire.requestFrom(8,1);

// request 1 byte from slave arduino (8)
byte MasterReceive = Wire.read();

// receive a byte from the slave arduino and store in MasterReceive
int potvalue = analogRead(A0);

// Reads analog value from POT (0-5V)
byte MasterSend = map(potvalue,0,1023,0,127);

//Convert digital value (0 to 1023) to (0 to 127)

Wire.beginTransmission(8);

// start transmit to slave arduino (8)
Wire.write(MasterSend);

// sends one byte converted POT value to slave
Wire.endTransmission();

// stop transmitting
lcd.setCursor(0,0);

//Sets Currsor at line one of LCD
lcd.print(">> Master <<");

//Prints >> Master << at LCD
lcd.setCursor(0,1);

//Sets Cursor at line two of LCD
lcd.print("SlaveVal:");

//Prints SlaveVal: in LCD
lcd.print(MasterReceive);

//Prints MasterReceive in LCD received from Slave
Serial.println("Master Received From Slave");

//Prints in Serial Monitor
Serial.println(MasterReceive);
delay(500);
lcd.clear();

}

SLAVE:-

#include //Library for I2C Communication functions
#include //Library for LCD display function
LiquidCrystal lcd(2, 7, 8, 9, 10, 11);

//Define LCD Module Pins (RS,EN,D4,D5,D6,D7)

byte SlaveReceived = 0;

void setup()

{
lcd.begin(16,2);

//Initilize LCD display
lcd.setCursor(0,0);

//Sets Cursor at first line of Display
lcd.print("CYIENT");

//Prints CIRCUIT DIGEST in LCD
lcd.setCursor(0,1);

//Sets Cursor at second line of Display
lcd.print("I2C SLAVE ARDUINO");

//Prints I2C ARDUINO in LCD
delay(5000);

//Delay for 5 seconds
lcd.clear();

//Clears LCD display
Serial.begin(9600);

//Begins Serial Communication at 9600 baud rate
Wire.begin(8);

//Begins I2C communication with Slave Address as 8 at pin (A4,A5)
Wire.onReceive(receiveEvent);

//Function call when Slave receives value from master
}

void loop(void)
{
lcd.setCursor(0,0);

//Sets Currsor at line one of LCD
lcd.print(">> Slave <<");

//Prints >> Slave << at LCD
lcd.setCursor(0,1);

//Sets Cursor at line two of LCD
lcd.print("MasterVal:");

//Prints MasterVal: in LCD
lcd.print(SlaveReceived);

//Prints SlaveReceived value in LCD received from Master
Serial.println("Slave Received From Master:");

//Prints in Serial Monitor
Serial.println(SlaveReceived);
delay(500);
lcd.clear();

}

void receiveEvent (int howMany) /

/This Function is called when Slave receives value from master
{
SlaveReceived = Wire.read();

//Used to read value received from master and store in variable SlaveReceived
}