Pushbutton Debouncing Filter Help

Using Arduino Programming Questions
1

I'm new to Arduino, and I'm trying to implement a debouncing code function that will be used in a pushbutton circuit I have that is using a 7 segment display to count every pushbutton press from 0 to 9.

The problem I'm having is when I run the code, my display is stuck on 0, and won't recognize any presses. Any help would be appreciated!!

I'm using the Uno R3 Arduino

const int a=2;
const int b=3;
const int c=4;
const int d=5;
const int e=6;
const int f=7;
const int g=8;
const int buttonPin = 9; 
int validButtonPress = 0;
int count = 0;
int buttonPress = 0;
int buttonState = 0;  
int lastButtonState = 0;
long lastDebounceTime = 0;
long debounceDelay = 50;

void setup() 
{
  //Designating input/output pins
pinMode(buttonPin, INPUT); 
pinMode(a, OUTPUT);
pinMode(b, OUTPUT);
pinMode(c, OUTPUT);
pinMode(d, OUTPUT);
pinMode(e, OUTPUT);
pinMode(f, OUTPUT);
pinMode(g, OUTPUT);
}
void loop()
{
  if (readButton(buttonPin) == 1)
      
  buttonState = digitalRead(buttonPin);
  //Checking for a button press
  if  (validButtonPress == 1)
  {
   if (buttonState != lastButtonState)
     //counting function
   {
    if (buttonState == 1)
    {
     count++;
      
    }

    else 
    {
    }
    }
  }
      
  
lastButtonState = buttonState;

  //Switch case for incrementing LED counter
switch(count)
  {
    case 0:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, LOW);
    digitalWrite(f, LOW);
    digitalWrite(g, HIGH);
    break;

        case 1:
    digitalWrite(a, HIGH);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, HIGH);
    digitalWrite(e, HIGH);
    digitalWrite(f, HIGH);
    digitalWrite(g, HIGH);
    break;

        case 2:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, HIGH);
    digitalWrite(d, LOW);
    digitalWrite(e, LOW);
    digitalWrite(f, HIGH);
    digitalWrite(g, LOW);
    break;
        case 3:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, HIGH);
    digitalWrite(f, HIGH);
    digitalWrite(g, LOW);
    break;
  
        case 4:
    digitalWrite(a, HIGH);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, HIGH);
    digitalWrite(e, HIGH);
    digitalWrite(f, LOW);
    digitalWrite(g, LOW);
    break;

        case 5:
    digitalWrite(a, LOW);
    digitalWrite(b, HIGH);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, HIGH);
    digitalWrite(f, LOW);
    digitalWrite(g, LOW);
    break;
  
        case 6:
    digitalWrite(a, LOW);
    digitalWrite(b, HIGH);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, LOW);
    digitalWrite(f, LOW);
    digitalWrite(g, LOW);
    break;

       case 7:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, HIGH);
    digitalWrite(e, HIGH);
    digitalWrite(f, HIGH);
    digitalWrite(g, HIGH);
    break;

        case 8:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, LOW);
    digitalWrite(f, LOW);
    digitalWrite(g, LOW);
    break;
  
        case 9:
    digitalWrite(a, LOW);
    digitalWrite(b, LOW);
    digitalWrite(c, LOW);
    digitalWrite(d, LOW);
    digitalWrite(e, HIGH);
    digitalWrite(f, LOW);
    digitalWrite(g, LOW);
    break;
  
 default: count=0; break; 
  } 

}
//Attempted debouncing code
int readButton(int buttonPin)
{
  int validButtonPress = 0;
  int reading = digitalRead(buttonPin);
  if (reading != lastButtonState)
    lastDebounceTime = millis();
  if ((millis() - lastDebounceTime) > debounceDelay)
    if (reading != buttonState)
  {
    buttonState = reading;
    if (buttonState == HIGH)
      validButtonPress = 1;
  }
  lastButtonState = reading;
  return validButtonPress;
}
2

Here's one way to handle debouncing. After a button is pressed, you set up a counter which is decremented each time you successfully detect that the button is released. If you detect a press, you start over counting.

/*
This is Arduino polling code for pin D4 as button A, low when pressed.
It reacts immediately to a button press, but then requires the button
to be released continuously for 100mS before another press is recognized.
*/


//in setup:

int newCount = 100;
int button_A_count = 0;
unsigned long newMilli_A;
unsigned long oldMilli_A;
int buttonApin = 4;


// in loop:

if (button_A_count) {
  newMilli_A = millis();
  if (oldMilli_A_ != newMilli_A) {
    oldMilli_A = newMilli_A;
    button_A_count--;
    if (digitalRead(buttonApin) == LOW) button_A_count = newCount;
  }
}

else if (digitalRead(buttonApin) == LOW) {
  button_A_count = newCount;
  oldMilli_A = millis();
  .
  .
  .
  whatever you want to do in response to a button_A press
  .
  .
  .
}

// same setup and loop code for button B, button C, etc.
3

for such a simple case, why not just add a 10 ms delay?

4

Have a read of Buttons and other electro-mechanical inputs (introduction) - General Electronics - Arduino Forum

5

You can use my DebouncedSwitch library. See the tutorial for examples and the code.

6

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