Tag Archives: electronic dice

Video: Electronic dice go random with AVR



A Maker named Walter recently created an entropy library for Atmel AVR microcontrollers (MCUs) to ensure a reliable source of truly arbitrary numbers.

As HackADay’s Brian Benchoff reports, the electronic dice generate random numbers by taking advantage of the watchdog timer’s natural jitter.

“[This isn’t] fast by any means but most sources of entropy aren’t that fast anyway,” Benchoff explains. “By sampling a whole lot of AVR chips and doing a few statistical tests, it turns out this library is actually a pretty good source of randomness, at least as good as a pair of dice.”

According to Benchoff, the circuit itself employs a pair of 8×8 LED matrices from Adafruit, an Atmel-based Arduino board and a pair of buttons.

Supported modes (11 total)?

  • 2d6
  • 2d4
  • 2d8
  • 2d10
  • 1d12
  • 1d20
  • Deck of cards
  • Single hex number
  • Single 8-bit binary number
  • 8 character alphanumeric password

Interested in learning more? You can watch the video above or check out the project’s official page here.

Glossy Arduino Project Handbook details 45 projects

Mark Geddes has put together an Arduino Project Handbook about the Atmel-powered boards that boasts over 45 detailed projects illustrated in full color.

Examples include a lie detector, programmable rocket launcher, motion sensor alarm, reaction timer, electronic dice, keypad entry system, laser trip wire alarm, robot, wireless ID card system and range finder.

“Back in the late 80’s I was tinkering with electronics, programming and creating gadgets. Wind forward a few years (quite a few!) with an honors degree in design, two kids and a career in economic development, I’ve rediscovered my passion for creating. I’ve discovered the Arduino and can now recreate those gadgets from long ago but this time using a ‘brain’ to control them,” Geddes explained in a recent Indiegogo post.

“I like books. I like visual books. I like practical books. I like books that are all of these things! [So] I decided to experiment with the Arduino and create a record of my achievements that I could refer back to and share with my 10 year old son – this book is a result of that. This is the type of book I was looking for but didn’t exist, I hope that now it does, you might want it too.”

According to Geddes, the Arduino Project Handbook is ideal for schools, MakerSpaces, DIY novices and even veteran Makers.

The book – which features 192 full color pages – will be professionally printed, bound and sealed with a gloss finish on each page. The 45 projects are accompanied by images, schematics, code and ideas for how to use the detailed circuit in other projects.

Interested in learning more? You can check out the project’s official Indiegogo page here.