// The library for I2C communication
#include <Wire.h>

// Slave address
#define SLAVE_ADDRESS 0x55
// Button pin
#define BUTTON_PIN 8

void setup() {
  // Initializing the communication
  Wire.begin();
  // Initializing the serial port
  Serial.begin(115200);
  // Initializing the button as INPUT
  pinMode(BUTTON_PIN, INPUT);
}

void loop() {
  // It checks the last state of the button
  static bool lastButtonState = HIGH;
  // It reads if the button is high or low
  bool buttonState = digitalRead(BUTTON_PIN);

  // If button is Low(PUSH) and the last state of the button
  if (buttonState == LOW && lastButtonState == HIGH) {
    // Initializes the communication with the slave
    Wire.beginTransmission(SLAVE_ADDRESS);
    // It sends a '1' to the slave
    Wire.write('1');
    // Ends the communication
    Wire.endTransmission();
    // Delay for the button debounce
    delay(100);
  }
  // It updates the state of the button
  lastButtonState = buttonState;
}