Animated Matrix Dice

This electronic dice is a remake of Thomas Angielsky's Shaking Arduino Dice (https://www.hackster.io/tangielsky/shaking-arduino-dice-39fc6a)

Video
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https://youtu.be/xUGiYDywZfw

Design
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The goal of this remake was to reduce the size of the final unit. The aim was to make it no wider than the LED Matrix itself. The Arduino Nano was replaced with a Digispark board. Later the Digispark board itself was replaced with a single ATTiny85 IC. The software had to be modified to