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

Aim :

To implement  this project 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).

Main code :

#include
#include // Header to use I2C communication
LiquidCrystal lcd(2,3,4,5,6,7);

void setup()

{
lcd.begin(16,2); //Initilize LCD display
lcd.setCursor(0,0); //Sets Cursor at first line of Display
lcd.print("Starting"); //Prints STARTING in LCD
lcd.setCursor(0,1); //Sets Cursor at second line of Display
lcd.print("I2C 1 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
//lcd.print(analogRead(A0));
Serial.println("Master Received From Slave");//Prints in Serial Monitor
Serial.println(MasterReceive);
delay(500);
lcd.clear();

}

//Slave code.
#include
#include // Header to use I2C communication
LiquidCrystal lcd(2,3,4,5,6,7);
byte SlaveReceived = 0;

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 into digital value
//(0 to 1023) to (0 to 127)
Wire.write(SlaveSend); // sends one byte converted POT value to master
}

 void setup()

{
lcd.begin(16,2); //Initilize LCD display
lcd.setCursor(0,0); //Sets Cursor at first line of Display
lcd.print("Starting"); //Prints STARTING in LCD
lcd.setCursor(0,1); //Sets Cursor at second line of Display
lcd.print("I2C 2 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();

}