Wouldn't it be awesome if you could control a matrix without tons of wiring? That's where these lovely LED matrix backpacks come in.
The matrices use a driver chip that does all the heavy lifting for you: They have a built in clock so they multiplex the display. They use constant-current drivers for ultra-bright, consistent color (the images above are photographed at the dimmest setting to avoid overloading our camera!), 1/16 step display dimming, all via a simple I2C interface. These 1.2" matrix backpacks come with three address-selection jumpers so you can connect up to eight 1.2" 8x8's together (or a combination, such as four 1.2" 8x8's and four 7-segments, etc) on a single I2C bus.
The product kit comes with:
A bit of soldering is required to attach the matrix onto the backpack but its very easy to do and only takes about 5 minutes.
Of course, in classic Adafruit fashion, they also have a detailed tutorial showing you how to solder, wire and control the display. they even wrote a very nice library for the backpacks so you can get running in under half an hour, displaying images on the matrix or numbers on the 7-segment. If you've been eying matrix displays but hesitated because of the complexity, this is the solution you've been looking for!
This board/chip uses I2C 7-bit addresses between 0x70-0x77, selectable with jumpers.