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

//master arduino
//I2C Communication between two arduino

//library for I2C communication function
#include
#include
//Define LCD module pins

LiquidCrystal lcd1(2,7,8,9,10,11);
byte MasterSend;

void setup()
{
Wire.begin();//Begin I2C communication at A4,A5

Serial.begin(9600);//Begin Serial communication at 9600 band rate
}
void loop()//using loop function
{
//
Wire.requestFrom(11,1);//request 1 byte from slave arduino(2)

byte MasterReceive = Wire.read();//receive a byte from the slave arduino and store in masterReceived

float value = analogRead(A0); //read analog value from value

byte MasterSend = map(value,0,1023,0,127);//convert digital value (0 -1023) to (0 -127)

Wire.beginTransmission(11); //start transmit to slave arduino

Wire.write(MasterSend);//send one byte converted value to slave

Wire.endTransmission();

lcd1.begin(16,2);//intialize LCD display size 16x2

lcd1.setCursor(0,0);

lcd1.print("");

lcd1.setCursor(0,1);

lcd1.print("slave value :");

lcd1.print(MasterReceive);

//print in serial monitor
Serial.print("\n master from slave");

Serial.println(MasterReceive);

delay(1000);

}

//I2C SLAVE CODE

//I2C Communication between Two Arduino

//CircuitDigest

//Pramoth.T

#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

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

Wire.onRequest(requestEvent); //Function call when Master request value from Slave

}

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

}

void requestEvent() //This Function is called when Master wants value from slave

{

int potvalue = analogRead(A0); // Reads analog value from POT (0-5V)

byte SlaveSend = map(potvalue,0,1023,0,127); // Convert potvalue digital value (0 to 1023) to (0 to 127)

Wire.write(SlaveSend); // sends one byte converted POT value to master

}