Arduino: DigitalButton - Button library with click and long-press detection

A comprehensive button handling library with debouncing, click detection, and long-press support for Arduino. Perfect for reliable button input with minimal configuration.

Features

• Click and long-press detection with configurable timing
• Automatic debouncing (eliminates mechanical noise)
• Support for INPUT and INPUT_PULLUP modes
• Simple API with minimal setup

Installation

Arduino IDE Library Manager

1. Open Arduino IDE
2. Go to Sketch → Include Library → Manage Libraries
3. Search for "DigitalButton"
4. Click Install

Manual Installation

1. Download this repository as ZIP
2. In Arduino IDE: Sketch → Include Library → Add .ZIP Library
3. Select the downloaded ZIP file

Quick Start

#include <DigitalButton.h>

// Create button instance (pin 2, use internal pull-up)
DigitalButton button(2, true);

void setup() {
  Serial.begin(9600);
  button.begin();  // Initialize button
}

void loop() {
  button.update();  // Update button state (must be called every loop)

  // Detect short press and release
  if (button.isClicked()) {
    Serial.println("Button clicked!");
  }

  // Detect long press (held for 1000ms by default)
  if (button.isLongPressed()) {
    Serial.println("Button long pressed!");
  }

  delay(10);
}

Examples

See the examples/ directory for complete usage examples:

• Basic: Simple button usage with all detection methods
• CustomTiming: Custom debounce and long-press timing configuration
• ExternalPullDown: Using external pull-down resistor instead of internal pull-up
• MultipleButtons: Handling multiple buttons simultaneously

API Reference

Constructor

DigitalButton(uint8_t pin, bool useInputPullUp, unsigned long debounceDelay = 20, unsigned long longPressDelay = 1000)

Create a new button instance.

Parameters:

• pin: Arduino pin number connected to the button
• useInputPullUp: true to enable internal pull-up resistor (button connects to GND), false for external pull-down (button connects to VCC)
• debounceDelay: Debounce time in milliseconds (default: 20ms)
• longPressDelay: Long-press threshold in milliseconds (default: 1000ms)

Example:

// Button on pin 2, internal pull-up, 20ms debounce, 1s long-press
DigitalButton button(2, true);

// Button on pin 3, external pull-down, 50ms debounce, 2s long-press
DigitalButton button(3, false, 50, 2000);

Methods

void begin()

Initialize the button pin and internal state. Must be called in setup().

Example:

void setup() {
  button.begin();
}

void update()

Update button state. Must be called regularly in loop() to detect state changes.

Example:

void loop() {
  button.update();
  // ... check button states
}

bool isPressed()

Check if button is currently pressed.

Returns: true if button is pressed, false otherwise

Example:

if (button.isPressed()) {
  Serial.println("Button is currently pressed");
}

bool isClicked()

Check if button was clicked (pressed and released quickly, not a long-press).

Returns: true for one loop iteration after a click is detected, false otherwise

Note: This returns true only once per click event. You must call it in every loop iteration to catch the event.

Example:

if (button.isClicked()) {
  Serial.println("Button was clicked!");
  clickCount++;
}

bool isLongPressed()

Check if button was long-pressed (held longer than longPressDelay).

Returns: true for one loop iteration after a long-press is detected, false otherwise

Note: This returns true only once per long-press event. You must call it in every loop iteration to catch the event.

Example:

if (button.isLongPressed()) {
  Serial.println("Button was held for a long time!");
  resetSettings();
}

Default Values

• Debounce Delay: 20 milliseconds
• Long-press Delay: 1000 milliseconds (1 second)

These values work well for most mechanical buttons but can be adjusted in the constructor:

// Custom timing: 50ms debounce, 2s long-press
DigitalButton button(2, true, 50, 2000);

Supported Platforms

This library is compatible with all Arduino platforms:

• Arduino UNO, Nano, Pro Mini
• Arduino Mega
• Arduino Leonardo, Pro Micro
• ATtiny 85, etc.
• And any other Arduino-compatible platform

License

MIT License - see LICENSE file for details.

Contributing

Pull requests and issues are welcome on GitHub.