A digital dice with a 7-segment display, shake animation, and multiple dice modes (D6, D12, D20) — triggered by a push button.
A 7-segment display has 7 LED segments (a–g). We control each segment to form digits 0–9.
// 7-segment pin mapping (common cathode display)
// Segments: a=2, b=3, c=4, d=5, e=6, f=7, g=8, DP=9
const int SEG[] = {2,3,4,5,6,7,8};
// Digit encoding: which segments are ON for each digit 0-9
// Segments: a b c d e f g
const bool DIGITS[10][7] = {
{1,1,1,1,1,1,0}, // 0
{0,1,1,0,0,0,0}, // 1
{1,1,0,1,1,0,1}, // 2
{1,1,1,1,0,0,1}, // 3
{0,1,1,0,0,1,1}, // 4
{1,0,1,1,0,1,1}, // 5
{1,0,1,1,1,1,1}, // 6
{1,1,1,0,0,0,0}, // 7
{1,1,1,1,1,1,1}, // 8
{1,1,1,1,0,1,1}, // 9
};
void setup() {
for (int i = 0; i < 7; i++) pinMode(SEG[i], OUTPUT);
}
void showDigit(int n) {
if (n < 0 || n > 9) return;
for (int i = 0; i < 7; i++)
digitalWrite(SEG[i], DIGITS[n][i]);
}
void loop() {
for (int d = 0; d <= 9; d++) { showDigit(d); delay(500); }
}Press the button to roll. The display shuffles through random numbers before landing.
const int BUTTON = 12;
const int MAX_FACE = 6; // D6 — change to 12 for D12, 20 for D20
void showDash() {
for (int i = 0; i < 7; i++) digitalWrite(SEG[i], i == 6 ? HIGH : LOW); // only segment g
}
int rollDice() {
return random(1, MAX_FACE + 1);
}
void animateRoll() {
// Shuffle animation: rapidly show random digits
int shuffleCount = random(10, 20);
for (int i = 0; i < shuffleCount; i++) {
showDigit(random(1, 10));
delay(50 + i * 8); // gradually slow down
}
}
void setup() {
randomSeed(analogRead(A5)); // seed from floating pin
for (int i = 0; i < 7; i++) pinMode(SEG[i], OUTPUT);
pinMode(BUTTON, INPUT);
showDash();
Serial.begin(9600);
}
void loop() {
if (digitalRead(BUTTON) == HIGH) {
delay(50); // debounce
if (digitalRead(BUTTON) == HIGH) {
animateRoll();
int result = rollDice();
if (result <= 9) {
showDigit(result);
} else {
// Flash two-digit result for D12/D20
for (int flash = 0; flash < 6; flash++) {
showDigit(result / 10); delay(300);
showDigit(result % 10); delay(300);
}
showDigit(result % 10); // leave last digit showing
}
Serial.print("Rolled: "); Serial.println(result);
while (digitalRead(BUTTON) == HIGH); // wait for release
}
}
}A satisfying physical gadget in 50 lines of code. The same button-debounce + display pattern is used in digital scoreboards, combination locks, and number entry keypads.
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