Minimatrix is a tiny (3cm x 3cm) battery powered LED matrix display, reprogrammable over infra-red. It displays marquee text and short animations, which can be programmed using an infrared remote control or from a computer via an Arduino or similar development platform. You can even use it as an interactive display by updating it live!

Minimatrix is based around a small single-color LED matrix and an ATTiny4313 microcontroller. It’s powered by a single coin cell battery, which will last for up to 18 hours hours of continuous operation and months on standby. An IR receiver allows it to receive instructions and data from other embedded devices and standard IR remote controls.

Note that the minimatrix in the video is an early model - the photos show the latest version!

What you get

Your order includes a minimatrix kit in your choice of either red or green, and a CR2032 battery. The IR remote, which is optional but highly recommended, is available separately here.

The minimatrix comes as a kit, with all surface-mount parts soldered, leaving just the battery holder, IR receiver, button and matrix to solder together. If you'd prefer not to solder them yourself, you can get a fully soldered one for $5 extra.

Due to Royal Mail shipping restrictions, orders for more than 4 minimatrixes will ship without batteries. If you'd like to place a large order, please get in touch ahead of time to discuss!

Firmware

Minimatrix comes preprogrammed with versatile firmware that can do everything you see in the video and more. You can reprogram it yourself, of course, though you'll need a tag-connect cable - due to the limited space, there's no room for a standard ISP header!

Want a minimatrix for free? Contribute a feature, enhancement, or bugfix to the firmware and I'll send you one totally free of charge, anywhere in the world. What counts as an improvement? Here's a few examples:

• Adding a useful new feature
• Fixing an outstanding bug
• Improving code size
• Improving the build or test process