how-to-build-an-arduino-powered-led-dice

how-to-build-an-arduino-powered-led-dice.js

/* Define the GPIO pins each LED is connected to */
int leftTop = 2;
int leftMiddle = 3;
int leftBottom = 4;
int middleMiddle = 5;
int rightTop = 6;
int rightMiddle = 7;
int rightBottom = 8;

/* Save them in an array so we can easily iterate all of them. */
int ledPins[] = {
 leftTop,
 leftMiddle,
 leftBottom,
 middleMiddle,
 rightTop,
 rightMiddle,
 rightBottom
};

int numLedPins = 7;

/* Create arrays that hold which pins are part of which dice rolls. */
int one[] = { middleMiddle };
int two[] = { leftTop, rightBottom };
int three[] = { leftTop, middleMiddle, rightBottom };
int four[] = { leftTop, leftBottom, rightTop, rightBottom };
int five[] = { leftTop, leftBottom, middleMiddle, rightTop, rightBottom };
int six[] = { leftTop, leftMiddle, leftBottom, rightTop, rightMiddle, rightBottom };

/* All possible rolls. */
int* rolls[] = { one, two, three, four, five, six };

/* The pin the button is connected to. */
int buttonPin = 12;

void setup() {
  /* Setup the button as an input. */
  pinMode(buttonPin, INPUT);

  /* Set all LED pins as outputs. */
  for(int i = 0; i < numLedPins; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
}

/* These are all used for debouncing the button.
 * From here: https://www.arduino.cc/en/Tutorial/Debounce
 */
int currentButtonState = 0;
int buttonState = 0;
int lastButtonState = 0;
long debounceDelay = 50;
long lastDebounceTime = 0;

/* the loop function runs over and over again forever */
void loop() {

  currentButtonState = digitalRead(buttonPin);

  if(currentButtonState != lastButtonState) {
    lastDebounceTime = millis();
  }

  if((millis() - lastDebounceTime) > debounceDelay) {

    if(currentButtonState != buttonState) {
      buttonState = currentButtonState;

      if(buttonState == HIGH) {
        shuffle();
        roll();
      }
    }
  }

  lastButtonState = currentButtonState;
}

/*
 * Rolls a dice by randomly choosing a number and
 * lighting up the appropriate LEDs.
 */
void roll() {

  /* Randomly pick a dice roll. */
  int number = random(0, 6);

  /* Grab the pins that make up this roll. */
  int* rollPins = rolls[number];

  /* Turn off all LEDs. */
  for(int i = 0; i < numLedPins; i++) {
    digitalWrite(ledPins[i], LOW);
  }

  /* Turn on the LEDs that repesent the dice roll. **
  for(int i = 0; i < number + 1; i++) {
    digitalWrite(rollPins[i], HIGH);
  }
}
/*
 * Animates the dice by rolling them several times.
 */
void shuffle() {
  for(int i = 0; i < 25; i++) {
    roll();
    delay(40);
  }
}