Hands On with the KeyChainino


If you play with your keys while waiting on something: bus, subway, fish to bite, etc., the KeyChainino might be a good device to have handy. Creator Alessandro Matera was nice enough to send me one of these devices* to try out.

It’s a pretty neat device, and I really enjoy seeing the default Arkanoid-style game played on a 5×6 LED matrix. If you get tired of that, these LED devices can be programmed using an Arduino. Although it’s not as simple as programming an Arduino directly, the task shouldn’t be too hard to execute (I’ve programmed ATTiny chips before using an Arduino, as seen here).

Pins are provided with the board, so don’t discard them, or things will be slightly harder if you want to change the program around. Several programs, or sketches are available on the Keychainino site, though it would seem the real fun would be in creating or modifying your own programs. Granted, I just received this board and haven’t tried it yet, but that seems like the real fascinating thing about this little project.

Check out the video after the “read more” to see it in action:

One should note that you need to provide your own CR2032 coin cell battery for this unit. Fortunately, I had quite a few left over from this 20-pack I ordered from Amazon a few years ago. Considering what stores generally charge for one of these, it seems like it was a good purchase!

*I paid shipping charges


  1. Tindie Blog | Keychainino – An Arduino and LEDs for Your Keys - pingback on January 23, 2017 at 12:10 pm

Trackbacks and Pingbacks: