#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET);

const int buttonPin = 2;

volatile bool buttonPressed = false;

void handleButtonInterrupt() {
  buttonPressed = true;
}

void setup() {
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.display();
  delay(50);
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(WHITE);
  

  pinMode(buttonPin, INPUT_PULLUP);

  attachInterrupt(digitalPinToInterrupt(buttonPin), handleButtonInterrupt, FALLING);
}

void loop() {
  if (buttonPressed) {
    display.clearDisplay();
    display.setCursor(10, 10);
    display.print('@');
    display.display();

    buttonPressed = false;
  }
}