#include <LiquidCrystal_I2C.h>
 
LiquidCrystal_I2C lcd(0x27,20,4);

#define LED_PIN 13
#define BTN_PIN A3

int last_btn_value = LOW;
int btn_counter = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(LED_PIN, OUTPUT);
  pinMode(BTN_PIN, INPUT);

  lcd.init();
  lcd.backlight();

  lcd.print("BTN COUNTER");
}

void loop() {
  int current_btn_value = digitalRead(BTN_PIN);
  if (current_btn_value != last_btn_value) {
    if (current_btn_value == HIGH) {

    digitalWrite(LED_PIN, HIGH);

    } else {
          btn_counter++;
    lcd.setCursor(0,3);
    lcd.print(btn_counter);
    digitalWrite(LED_PIN, LOW);

    }
    last_btn_value = current_btn_value;
  } 

  delay(50);
}