Inspired by Les Pounder’s hacking, I spent a quid on some LED pumpkin lights and thought I’d make something fun for the trick-or-treaters this year. I wanted the lights to come on and a spooky sound effect to play when a button is pressed on my little box of horrors.

Halloween lights

As Les suggested I removed the battery box from the LEDs, and then extended the wires with some hook up wire. I also found and edited some nice spooky sfx, which I saved onto the Zero.

The Raspberry Pi Zero has no audio output, so I added a pHAT DAC from Pimoroni; remembering to use extended headers so I could later add a ProtoZero board to tidily solder the wires onto.

Halloween lights

For the first prototype I connected the LEDs to a GPIO pin and the ground pin and started by writing some code that just made them come on and then go off again after a few seconds. Next I added a button which switched the lights on. Finally I used Pygame mixer to play the audio file at the same time as the lights come on.

The code looks like this:

# Import Python libraries
import RPi.GPIO as GPIO
import time
import pygame
# Set the GPIO caming convention
GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
# Set the GPIO pins for button input and LED output
GPIO.setup(3, GPIO.IN, pull_up_down = GPIO.PUD_DOWN)
GPIO.setup(24, GPIO.OUT)
pygame.mixer.init()
pygame.mixer.load(Laugh.wav)
while True:
if(GPIO.input(3) ==0):
GPIO.output(24, GPIO.HIGH)
pygame.mixer.music.play()
time.sleep (10)
GPIO.output(24, GPIO.LOW)
GPIO.cleanup

I went back to my favourite Instructable on launching Python scripts at startup and then set about cramming it all – including USB powered speakers and a USB power bank – into a Celebrations box that I’d kept because it looked useful. I drilled a small hole in the side to pass the LED’s wires through, and a big hole in the lid for an arcade button. It’s a bit of a squeeze to get to the lid on, but it all just about fits in.

Halloween lights

There are plenty of things I could do to make this better. For instance…

  • At the moment it plays the same sound every time the button is pressed, but it’d be nice to play a random selection from a playlist of sounds
  • The lights could flicker and flash while the sound plays instead of being constantly on
  • If the sounds are of varying lengths the lights should only be on for as long as each sound plays
  • The lights and sounds could be swapped for Christmas or other gaudily celebrated occasions
  • Spray paint and decorate the box to be a bit less chocolate-boxy
  • Re-write it in gpiozero