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ATtiny OLED Watch Core

ATtiny OLED Watch Core

陳亮 from shows us his ATtiny85 OLED display build on a breadboard:

This instructable show how to use an ATtiny85 to create a tiny watch core that can run over 1 year before recharge or replace battery.

The instruction to make the watch case may be in next instructable.

I have made a few Arduino watch before, but I found the watch using ATmega boards or ATmega chips are a little bit too big to wear. So I would like to make it with a smaller chips.

I have choose ATtiny85 just because I can easy to get one.

The challenges for using ATtiny85 are:


  1. It only have 8K flash memory
  2. It only have 5 IO pins (I would like to keep the 6th IO pin as reset for easy re-programming)
  3. Since the above 2 limitations, it is hard to find a complete source code for an ATtiny watch on the web

I design to develop a tailor-make code to complete these challenge, it include:

  1. Power control to make the watch can run over 1 year
  2. Revise a time library to utilize WDT for power saving purpose
  3. Trim down a display library to meet 8K binary limitation
  4. Customizable font type
  5. Basic UI for adjust time just like a normal digit watch

ATtiny OLED Watch Core – [Link]