Game&Light a keychain size game console with a led

An Attiny 402 based console, powered by an LIC 40F.
Work in progress!

Similar projects worth following
I wanted to make a as cheap as possible game console to carry with your keys, rechargeable and easy to flash without soldering.
This is the first prototype of that idea that is based on the Attiny 402, it uses an LIC as battery and the microcontroller itsefls controls the charging with a mosfet.
The capacitor gives around 40 min of gameplay with a 5 min. charge.

You can download and test the game here, it should work on any attiny series 0, 1 or 2 just change the pins number to fit the micro you use. To test the game you just need to wire the screen and button.


Timer and temp display:
Wrist watch:

New April 2022 update!

So far the state of the project:

Finished / pros:

-Cheap and use very few parts

-Rechargeable, the LIC works really nice and it recharges quickly, also no dropping.

-The microcontroller manages the charging  so no need to add a voltage regulator.

-It can be flashed with the usb cable, not standard though,  UPDI needs to be feed intro the D+ signal of USB with a flashing solution like serial to UPDI, I know it isn't standard but it is very convenient and it works really well.

-Now charging works ok using a mosfet controlled by timer A .

-Sleep is implemented.

-Whatchdog is implemented to wake up from sleep every 4 sec.  checks  if device is charging and if the  voltage is below 3.8v and above 2.2v to protect the LIC.

(also resets if hung)

To do / cons:

- Although using the usb to feed the UPDI signal is practical, I don't know if  it would damage a computer if it is connected to it, it shouldn't since the UPDI is pulled up with a 30k resistor but still a concern.

In case of connecting it directly to USB by mistake, using the UPDI adapter to send the signal is ok. 

I tested once and nothing happened  but  doing it repeatedly is another story.

- 4k of flash is a small amount, in my case I have to chop content of the game, someone with more knowledge I am sure can fit more, considering in using a bigger micro????.



x-zip-compressed - 59.19 kB - 08/03/2022 at 01:48



plain - 723.00 bytes - 08/03/2022 at 01:48



Portable Network Graphics (PNG) - 30.33 kB - 08/03/2022 at 01:45


watch body.stl

watch body (intended to be used with Xiaomi Mi 3/4 band)

Standard Tesselated Geometry - 152.91 kB - 07/26/2022 at 02:16


watch face.stl

wrist watch faceplate

Standard Tesselated Geometry - 92.17 kB - 07/26/2022 at 02:16


View all 10 files

View all 4 project logs

Enjoy this project?



grossofabian wrote 04/04/2022 at 17:10 point

Thanks for your comment, that would be ideal, if all of us could join forces and make a standard, I am sure it would have awesome games, I think the closest one is the Arduboy.

  Are you sure? yes | no

dearuserhron wrote 04/04/2022 at 10:35 point

Love it. There are a lot of custom microcontroller projects with small screen. My superidea is to make everyone of them compatible. I know it is hardly impossible, but still trying.

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates