#include <LiquidCrystal.h>
#include "Button.h"

Button incrementButton(A0);
Button decrementButton(A1);
Button resetButton(A2);
LiquidCrystal lcd(12, 11, 10, 9, 8, 7);

int counter = 0;    

const int relaySwitch = 3;  

void setup() {
  pinMode(relaySwitch, OUTPUT);
  lcd.begin(16, 2);
  lcd.print("WELCOME");
  delay(500);
}

void loop() {
    if (incrementButton.pressed()) {
      counter++;
      lcd.clear();
      lcd.print(counter);
    }

    if (decrementButton.pressed()) {
      counter--;
      if(counter<0){
        counter = 0;
      }
      lcd.clear();
      lcd.print(counter);
    }

    if (resetButton.pressed()) {
      counter=0;
      lcd.clear();
      lcd.print(counter);
    }

    if(counter==10){
      digitalWrite(relaySwitch, HIGH);
    } else {
      digitalWrite(relaySwitch, LOW);
    }
}

lcd1602.ino

diagram.json

/*
	Button - a small library for Arduino to handle button debouncing

	MIT licensed.
*/

#ifndef Button_h
#define Button_h
#include "Arduino.h"

class Button
{
	public:
		Button(uint8_t pin, uint16_t debounce_ms = 100);
		void begin();
		bool read();
		bool toggled();
		bool pressed();
		bool released();
		bool has_changed();
		uint16_t repeat_count();
		void set_repeat(int16_t delay_ms, int16_t repeat_ms);

		const static bool PRESSED = LOW;
		const static bool RELEASED = HIGH;

	private:
		uint16_t repeats_since_press();

		uint8_t  _pin;
		uint16_t _delay;
		bool     _state;
		uint32_t _ignore_until;
		bool     _has_changed;
		uint16_t _reported_repeats;
		int16_t  _repeat_delay_ms;
		int16_t  _repeat_ms;
};

#endif


Button.h

/*
	Button - a small library for Arduino to handle button debouncing

	MIT licensed.
*/

#include "Button.h"
#include <Arduino.h>

Button::Button(uint8_t pin, uint16_t debounce_ms)
:  _pin(pin)
,  _delay(debounce_ms)
,  _state(HIGH)
,  _ignore_until(0)
,  _has_changed(false)
,  _reported_repeats(0)
,  _repeat_delay_ms(-1)
,  _repeat_ms(-1)
{
}

void Button::begin()
{
	pinMode(_pin, INPUT_PULLUP);
}

//
// public methods
//

bool Button::read()
{
	// ignore pin changes until after this delay time
	if (_ignore_until > millis())
	{
		// ignore any changes during this period
	}

	// pin has changed
	else if (digitalRead(_pin) != _state)
	{
		_state = !_state;

		if (_state == RELEASED)
		{
			_reported_repeats = repeats_since_press();
		}

		else
		{
			_reported_repeats = 0;
		}

		_ignore_until = millis() + _delay;
		_has_changed = true;
	}

	return _state;
}

// has the button been toggled from on -> off, or vice versa
bool Button::toggled()
{
	read();
	return has_changed();
}

// mostly internal, tells you if a button has changed after calling the read() function
bool Button::has_changed()
{
	if (_has_changed)
	{
		_has_changed = false;
		return true;
	}
	return false;
}

// how many repeated press events occured since the button was pressed
uint16_t Button::repeat_count()
{
	return _state == PRESSED ? repeats_since_press() : _reported_repeats;
}

// has the button gone from off -> on or pressed repeatedly
bool Button::pressed()
{
	if (read() == PRESSED)
	{
		uint16_t old_repeats = _reported_repeats;
		_reported_repeats = repeats_since_press();
		return (has_changed() || old_repeats != _reported_repeats);
	}
	else
	{
		return false;
	}
}

// has the button gone from on -> off
bool Button::released()
{
	return (read() == RELEASED && has_changed());
}

void Button::set_repeat(int16_t delay_ms, int16_t repeat_ms)
{
	_repeat_delay_ms = delay_ms > _delay ? delay_ms - _delay : 0;
	_repeat_ms = repeat_ms;
}

uint16_t Button::repeats_since_press()
{
 	if (_repeat_delay_ms == -1 || millis() < _ignore_until + _repeat_delay_ms)
	{
		return 0;
	}

	if (_repeat_ms <= 0)
	{
		return 1;
	}

	uint32_t press_time = millis() - _ignore_until;
	return 1 + (press_time - _repeat_delay_ms) / _repeat_ms;
}


Button.cpp

# Wokwi Library List
# See https://docs.wokwi.com/guides/libraries

# Automatically added based on includes:
LiquidCrystal
# ---
