I2C example

The Slave Code

Below is the code for the Slave Arduino, which receives and processes data from the Master.

#include <Wire.h>

int LED = 13;

void setup() {

  pinMode(LED, OUTPUT);             // Set LED pin as output

  Wire.begin(6);                    // Join I2C bus with address #6

  Wire.onReceive(receiveEvent);     // Register receive event

  Serial.begin(9600);               // Start Serial Monitor for output

}

void loop() {

  delay(100); // Wait for data from Master

}

void receiveEvent(int howMany) {

  while (1 < Wire.available()) {    // Loop through all but the last byte

    char c = Wire.read();           // Receive byte as a character

    Serial.print(c);                // Print the character to Serial Monitor

    digitalWrite(LED, HIGH);        // Turn LED on

    delay(1000);

    digitalWrite(LED, LOW);         // Turn LED off

    delay(500);

  }

  int x = Wire.read();              // Receive the last byte as an integer

  Serial.println(x);                // Print the integer to Serial Monitor

}

Explanation:

1. The Wire.begin(6) function assigns address 6 to the Slave.

2. The Wire.onReceive(receiveEvent) function registers receiveEvent as the callback for received data.

3. The receiveEvent function processes incoming data:

• Characters are printed to the Serial Monitor.

• The LED blinks with each received message.

• The last byte (an integer) is printed separately.

Simulation in Proteus

1. Set Up the Components:

• Place two Arduino Uno boards in Proteus.

• Connect the SDA (A4) and SCL (A5) pins of both boards.

• Add a virtual terminal to display Serial Monitor output by rightclicking and selecting PLace > Virtual instrument > Virtul terminal

  
  
  

• Connect an LED to pin 13 of the Slave Arduino.

1. Load the Codes:

   • Load the Master and Slave codes into the respective Arduinos.

2. Run the Simulation:

• Start the simulation in Proteus.

• Observe the data being sent from the Master to the Slave.

• Watch the LED blink on the Slave and verify the output in the Serial Monitor.

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