Pocket Dice for Your Next Game Night!
Roll five electronic dice with the push of a button using Alec Sunyacz's ATtiny85-based device.
Dice are portable enough, but when you want to actually use them you have to find a flat surface – and make sure they don’t roll away. Alec Sunyecz wanted to play a game called Liar's Dice, which requires each player to have five dice each, making this more complicated than usual. To deal with this challenge, he created an ATtiny85-based electronic dice machine aptly called “Pocket Dice.”
As its name would suggest, the device is designed to fit in one’s pocket and features five dice faces with seven light-up dots each. Under each one dot lies a 0603 red LED for illumination, soldered to the build's PCB. For direct control of the LEDs, Sunyacz employed a MAX7219 driver, allowing an ATtiny85 to handle all 35 LEDs with three I/O pins. This setup also enables a DIP switch to turn on each die using its common cathode pin.
To roll, a button activates the dice, and one can even “shake” them by holding down the button. A 3D-printed housing and dice models complete the theme nicely. As seen in the video above, the process works quite well, giving users a nice simulation of actually rolling numerical cubes. Code, STLs, and lots more info are available in Sunyacz's project writeup if you want to build your own!