Button Debounce 21

Filter switch bounce with clean state transitions.

/*
  Roboda verified Arduino sample 0519
  Feature: Button Debounce
  Generated for online build, classroom practice, and hardware upload testing.
*/

const byte buttonPin = 2;
const byte ledPin = 13;
bool stableState = HIGH;
bool lastReading = HIGH;
unsigned long lastChange = 0;

void setup() {
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);
}

void loop() {
  bool reading = digitalRead(buttonPin);
  if (reading != lastReading) {
    lastChange = millis();
    lastReading = reading;
  }
  if (millis() - lastChange > 40) {
    stableState = reading;
  }
  digitalWrite(ledPin, stableState == LOW ? HIGH : LOW);
}

How it works

Practice this Arduino feature with a verified Roboda sketch.

1. Read the constants at the top of the sketch.
2. Wire the pins exactly as listed in the pin map.
3. Upload or compile once before changing values.
4. Change one value at a time and watch Serial Monitor or the output device.

Connections