Buzzle – Morse Code based Puzzle

Buzzle – Morse Code based Puzzle

I was checking out the new posts on when I bumped into The Reverse Geocache Puzzle™ made by Mikal Hart.

I was amazed by it, so I immediately decided to make one for a good friend as a birthday gift. As I thought it through an idea of doing a hangman-like-puzzle using Morse Code popped into my head, and that’s what came out:

It’s called “Buzzle”. It’s a locked box with a button on the front, a couple of LEDs on the top and a power plug on the back. When the button is pushed, it emits a ‘beep’. The longer you hold the button longer the box beeps.

Along with it is a card, like the one bellow, with instructions (in Portuguese… it’s enough to ask anyone to learn Morse Code):

The instructions goes basicly like this:
  • A random word is picked up by the box and the challenger’s goal is to find it out, by telegraphing the right letters sequentially until the word is complete;
  • The number of letters in the word is buzzed out via Morse Code at the beginning;
  • The evaluation is made letter-by-letter. At the completion of a letter, the box evaluates if:
    • The letter is valid and is contained in the word. If not a red LED will blink;
    • The letter is contained in the word, but is not the next letter of the sequence, so a yellow LED will blink;
    • The letter is contained and is the next letter of the sequence. In that case a green LED will blink, indicating that the challenger got a letter right. So it’s time to try the next letter (which may be any letters that triggered the yellow LED);
  • If the challenger get 10 errors (red LED), then he looses the game and it starts again with another word.

The hardest part of making it was thinking of the rules and how to feedback the challenger, for there are limited resources for that (a couple of LED).

Parts Used:

  • 1x – A box! I bought this one at Feira da Torre, at Brasília (Brazil).
  • 1x – Arduino Dicemillenove (I tryed a Boarduino, but since mine is buggy because of some wrong caps, the servo was twitching) – the brains
  • 1x – 180° Servo – Tower Pro SG90 – the muscles
  • 1x – Hashi (Japannese stick for eating) – the lock (which is 100% Mikal’s idea)
  • 1x – A push button (I used a open/closed one to make my life easier implementing the ’sleep mode’)
  • 1x – A 5V buzzer
  • 1x – Red-green-blue LED
  • 1x – Yellow LED (I wasn’t happy with the yellow-mixed of the tri-color LED)
  • 1x – A 9V battery snap connector (FAIL!)
  • 1x – Power plug (SAVED MY ASS!)
  • 1x – Wall adapter power supply 9V DC
  • 1x – An acrylic box for the components
  • Lots of 220Ω resistors and 2 diodes (for the power)