Electronic dice on an LED bar

Parts in this circuit

Wiring, pin by pin

Red = 5 V, orange = 3.3 V, black = GND, other colours = signals. “Pin” is the position on the 40-pin header; the GPIO number is what the code uses. Power the Pi from a 5.1 V supply and wire with the power off.

Python code (gpiozero)

from gpiozero import Button, LEDBarGraph
from random import randint
from time import sleep

button = Button(27)
bar = LEDBarGraph(5, 6, 13, 19, 26)

print("Press the Roll button")
while True:
    button.wait_for_press()
    for _ in range(12):                       # a quick "rolling" animation
        bar.value = randint(1, 5) / 5
        sleep(0.08)
    number = randint(1, 5)
    bar.value = number / 5                    # number of LEDs lit = the roll
    print("You rolled a", number)
    button.wait_for_release()

How the code works

• randint(1, 5) gives a whole number from 1 to 5.
• The loop shows 12 random numbers very quickly, which looks like a rolling die.
• bar.value = number / 5 lights that many LEDs out of five.

Parts to buy

The links open a search on each store, so you see what is in stock today. Check the model, voltage and price before you order.