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A project log for Dice10

How to control the 7 LEDs of a die with only 2 GPIO - a miniaturized electronic die based on ATtiny10.

timTim 11/26/2016 at 10:450 Comments

This is an attempt at an absolutely minimized electronics dice implementation. An entry for the Hackaday 1kb competition. Using an ATtiny10 as a MCU automatically limits the code size to 1kb, so the code size competition is automatically met.

The ATtiny10 only has three I/O lines - we need to control 7 LEDs in total. How?

This implementation manages to control all 7 LEDs using only two I/Os. See here for a description of the multiplexing scheme: https://cpldcpu.wordpress.com/2015/05/24/plexingplus/

Why no series resistors? Well, turns out you can get away with that when you minimize the duty cycle of the LEDs. Since the scheme required multiplexing anyways, this is automatically given.

The remaining I/O pin is used for a touch button to activate the dice. No push button is needed. I am using my TinyTouchLib for this, which also works on an ATtiny10.

https://github.com/cpldcpu/TinyTouchLib

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