#include <Adafruit_SSD1306.h> // Include the library for controlling the OLED display
#define BUTTON_PIN 3 // Define  pin 3 as the pin connected to  the button
#define SYMBOL "\x7F" //  non-alphanumeric symbol to display is defined here

// Create an Adafruit_SSD1306 object to control the display
Adafruit_SSD1306 display(128, 32, &Wire, -1);
//  a volatile bool variable is created to monitor whether the button has been pressed
volatile bool buttonPressed = false;

//  when button is pressed interrupt is set to true
void buttonInterrupt() {
  buttonPressed = true;
}

void setup() {
  Serial.begin(9600); // serial communication is initialized
  pinMode(BUTTON_PIN, INPUT_PULLUP); // the button pin is set as an input with a pull-up resistor
  attachInterrupt(digitalPinToInterrupt(BUTTON_PIN), buttonInterrupt, FALLING);
  //attach the interrupt to the button pin
  display.begin(SSD1306_SWITCHCAPVCC); // Initialize the OLED display
  display.clearDisplay(); // Clear the display
}

void loop() {
  if (buttonPressed) { 
    // this is to Check if the button has been pressed
    display.clearDisplay(); 
    // Clear the display
    display.setTextSize(3); 
    //the text sixze and color is set
    display.setTextColor(WHITE); 
   // Set the cursor position to be on top of the OLED display
    display.setCursor(0, 0); 
    display.print(SYMBOL); // Display the non-alphanumeric symbol
    display.display(); // Update the display
    buttonPressed = false; // Reset the buttonPressed flag
  }
}