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 allow it to fit in a ATTiny85 and the interrupt handlers had to change because the ATTiny85 only supports one interrupt vector for detecting pin changes.

A custom PC board was created to hold the vibration switches, ATTiny85, power switch and the 3.7V 120mA/Hr Battery. This board was created using the Toner method and is soldered onto the pins of the MAX7219/8x8 32mm Matrix board. Eagle files and Digispark sketch have been included. I programmed the ATTiny85 chip on my homemade Digispark boar