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

Aim:

Interfacing a 16*2 LCD with Arduino using I2C protocol.

Overview of the Project:

In this project implementing the Code for "Interfacing a 16*2 LCD with two Arduino's (one for Master and one for Slave) using Inter-Integrated Circuit (I2C) communication protocol" by sending the message to LCD using I2C communication protocol and display the message on LCD screen.

Goals:

• Communication between Arduino and 16*2 LCD using I2C protocol.
• Displaying the message sent by Master and received by slave i.e. LCD display.

Key Highlights of the Project:

• Using the inter-integrated circuit communication protocol, transferring the data i.e. the message we want to display is sent to the LCD.
• Two Arduino's connected to the LCD display and the communication is executed using I2C protocol between Arduino and the LDC display.

Deliverables of this project:

• Communication between the Arduino's and LCD using I2C.
• The message passed from master to slave and displayed on the 16*2 LCD.

Expected Outcomes:

• Students will get the Knowledge of I2C communication Protocol and the Arduino.
• The Hardware connection of all components used in this project.
• Displaying the message sent by master (Arduino) and received by the slave (16*2 LCD display).

Code:

//I2C MASTER CODE

#include <Wire.h> //Library for I2C Communication functions
#include <LiquidCrystal.h> //Library for I2C Communication functions
LiquidCrystal lcd(2,7,8,9,10,11); //Define LCD Module Pins (RS,EN,D4,D5,D6,D7)

void setup()
{
lcd.begin(16,2); //Initialize LCD display
lcd.setCursor(0,0); //Sets Cursor at first line of display
lcd.print("Circuit Digest"); //Print 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 sec
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 MasterRecieve = Wire.read(); //Recieved a byte from the slave arduino and store in MasterRecieves
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); //Set Cursor 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("MasterRecieves"); //Prints MasterRecieve in LCD recieved from slave
Serial.println("Master Recieved From Slave"); //Prints in Serial Monitor
Serial.println("MasterRecieves");
delay(500);
lcd.clear();
}

//I2C SLAVE CODE

#include<Wire.h> //Library for I2C Communication functions
#include<LiquidCrystal.h> //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("Circuit Digest"); //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
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
}

Circuit Module:

Output:

The message passed from master to slave and displayed on the 16*2 LCD:

When Varrying the potentiometer of master ,Slave recived from Master 40