144 Real LEDs. Not a Screen. 15 Games Built In.
This Is the Actual Device — Play It Right Here
This is the real KeyChainino 144 firmware, running right here in your browser — the same 15 games, the same icon menu, the same two-button controls as the real keychain. Pick a game, press play, and see what a 12×12 LED matrix can do.
144 Real LEDs. That’s the Whole Point.
The KeyChainino 144 doesn’t have a display — it has a 12×12 grid of 144 real LEDs, charlieplexed down to just 13 pins. We rewrote the driver from scratch for this firmware, so every LED sits at one of three honest brightness levels: off, dim, or bright. Backgrounds sit dim, the action sits bright, and the whole matrix keeps its own distinct, granular glow.
It’s not a screen — that’s the charm of it.
15 Games. One Icon Menu.
Arkanoid, Snake, Tetris, Invaders, Pong, Stacker, Frogger, Flappy, Racer, Simon, Jump, Catch, Whack, Dice and Life — all fifteen ship built in, ready to play the moment it arrives. Browse them from an icon menu with two buttons, and each game remembers your own best score, saved right on the device.
Where It Started
A few years ago I was waiting for a bus, fidgeting with my keys, and I thought: what if there was something fun built right into them? That’s how KeyChainino started — a tiny device to play with in boring moments, built around the Arduino platform I already loved.
The first version was a tiny 6×5 grid of 30 LEDs — no LCD, just charlieplexed LEDs and one simple Arkanoid-style game. From there it grew: KeyChainino V3 doubled the matrix to 64 LEDs, and today’s KeyChainino 144 drives a full 12×12 grid of 144 real LEDs, all on the same Arduino-compatible platform this project has always run on.
The 144 now ships with 15 full games built in, a menu to pick between them, and its own saved high score for each one — no reprogramming required. And because I still believe in the original idea, the firmware stays fully open source: if you want to dig in, change a game, or write your own, the same Arduino IDE and ISP guide that built this thing are right there for you.
— Alessandro Matera
See what Adafruit, Atmel, Geeky Gadgets and others say about KeyChainino!
P.S. If your game is really cool, send it to me and I will publish it with your credits!
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