How to prevent counter increment when holding the button

Question

I am a newbie and also a noobie. Kindly assist this poor boy over here. I am looking for a way to increment a variable by one each time a button is pressed. Current approach is the following :

void buttonLoop() {
 int win = 0;
 while (win ==0) {
 display.setCursor(0, 0);
 //getButtons() function can be used to test if any button is pressed, or used like:
 //getButtons(TSButtonUpperLeft) to test a particular button, or even like:
 //getButtons(TSButtonUpperLeft|TSButtonUpperRight) to test multiple buttons
 //results are flipped as you would expect when setFlip(true)
 if (display.getButtons(TSButtonUpperLeft)) {
 display.println("Pressed!");
 score++;
 updateScore();
 } else {
 display.println(" ");
 }
 display.setCursor(0, 54);
 if (display.getButtons(TSButtonLowerLeft)) {
 display.println("Pressed!");
 score++;
 updateScore();
 } else {
 display.println(" ");
 }
 display.setCursor(95 - display.getPrintWidth("Pressed!"), 0);
 if (display.getButtons(TSButtonUpperRight)) {
 display.println("Pressed!");
 score++;
 updateScore();
 } else {
 display.println(" ");
 }
 display.setCursor(95 - display.getPrintWidth("Pressed!"), 54);
 if (display.getButtons(TSButtonLowerRight)) {
 display.println("Pressed!");
 score++;
 updateScore();
 } else {
 display.println(" ");
 }
}
}

In my case, the counter will keep increasing if I do not let go of the button. How do I make it so that the counter will only increase by 1 even if i continue holding onto the button.

Thank you for all the kind souls in this society :)

• VE7JRO: Look for the Bounce2 library in the IDE library manager.
• jsotola: check to see if the button was released before allowing the counter to increment again

Answer 1

See my answer in this thread:

How to connect Big Dome Button with arduino

That thread explains how to wire up a switch and write code that increments a counter each time a button is pressed.

The bits you care about:

Connect one lead of the switch to a digital input, and the other lead to ground.

Then set your switch pin to INPUT_PULLUP mode. Now your switch will read HIGH until it's pressed, then it will read LOW.

create a variable at the top of your code called buttonState:

byte buttonState = HIGH;

Also define an unsigned long variable nextReadMillis:

unsigned long nextReadMillis = 0;

and a pressCount variable:

unsigned int pressCount = 0;

And define a debounceTime:

#define debounceTime 50

In your loop, do something like this:

void loop() {
 //Get the new millis(value)
 unsigned long newMillis = millis();
 //only look at the new button value if enough time has elapsed.
 if (newMillis >= nextReadMillis) {
 byte newButtonState = digitalRead(buttonPin);
 //Only do something if the button state has changed
 if (buttonState != newButtonState) {
 buttonState = newButtonState;
 nextReadMillis = newMillis + debounceTime;
 //If the button is now in the pressed (LOW) state, increment the count
 if (buttonState == LOW) {
 pressCount++;
 }
 }
 }
}

That's pseudo-code. It likely has syntax errors. It's not meant to be copy/pasted. Use it as a guide for your project.

The code using millis() is a version of "software debouncing." Electrical switches tend to "jitter" or "bounce" between their on and off states very rapidly when they are first pressed/released. By only checking for state changes after a brief delay, you ignore the jitter in the readings.

You can adjust the value of debounceTime up or down a little. A value of 50 is 1/20th of a second, which should make your button presses quite responsive, but still debounce the switch well. If you find your count sometimes increases by more than one for a button press, you can increase the value to 100 or even 500, although at 500 (1/2 second) the button won't respond to really rapid presses