wkoch / debounce

Arduino library for button debouncing.

Debounce

Really small Arduino library for button Debouncing. It's basically the Debounce example found on http://arduino.cc/en/Tutorial/Debounce wrapped as a library.

Really easy to use, with examples included.

Tested on an Arduino Due only.

Instructions

Include the library in your sketch:

#include <Debounce.h>

Constructor

Use one of this constructors, the default delay works great and is the recommended constructor.

Debounce Button With Default Delay

Create a Debounce object for your button, with a default delay of 50ms:

Debounce Button(4); // 4 is the pin, could be a variable too.

Debounce Button With a Custom Delay

Create a Debounce object for your button, with a custom delay:

Debounce Button(4, 80); // 4 is the pin, 80 is the delay, in ms.

Debounce Button With a Custom Delay and INPUT_PULLUP

Create a Debounce object for your button, with a custom delay and INPUT_PULLUP:

Debounce Button(4, 80, true); // 4 is the pin, 80 is the delay in ms, true for INPUT_PULLUP.

Note: This constructor will change the button input pin to INPUT_PULLUP.

Functions

Debounce has only a few easy to use functions.

read()

Inside your code, Button.read(); reads your button state and returns HIGH or LOW after debouncing it. It should always return HIGH when the button is pressed, and LOW otherwise.

This will turn the led on pin 13 ON when the button is pressed and debounced, it stays on until you release the button.

void loop() {
  digitalWrite(13, Button.read());
}

count()

Returns the counter of changes ocurred to the button. The counter will increase by 1 each time you press the button for longer than the debounce time. It will also increase by 1 when you release the button after it was debounced.

This will turn the led only when the button has been pressed and released 5 times. Turns Off after another 5 press-and-releases.

if (Button.count() == 10) {
  digitalWrite(13, HIGH);
} else {
  digitalWrite(13, LOW);
}

resetCount()

Resets the counter for the button changes.

debounce's Issues

Examples don't match with invert

With the addition of the invert, the examples with a custom delay no longer work as this has become ambiguous. When a custom delay is wanted, I guess this makes the extra parameters required?

From one of the examples:
Debounce Button2(button2, 70); // Button2 debounced, custom 70ms delay.
This now generates an error:
call of overloaded 'Debounce(byte&, int)' is ambiguous

This would work though:
Debounce Button2(button2, 70, false, false);

wrong constructor in README for INPUT_PULLUP

The example constructor for "Debounce Button With a Custom Delay and INPUT_PULLUP" shown in README.md is missing the third boolean argument.

Button Off Time (High) is same as delay time

Debounce Button1(button1, 30000,false,false);
//if delay is 30 seconds then led will turn on after 30 seconds but it will remain on for another 30 seconds after button is release.

INPUT_PULLUP is inconstant to the readme

In the readme, it appears that only if you put the 3rd variable in the Debounce Button(2,80,true) that it appears that the pull_down is default, where the default is true.

It might be best to change Debounce.h from
25 Debounce(byte button, unsigned long delay = 50, boolean pullup = true);

to
25 Debounce(byte button, unsigned long delay = 50, boolean pullup = false);