Geek built the Meggy Jr. RGB from the Evil Mad Scientist Laboratories store. It was moderately challenging to solder because Geek hasn’t done a great deal of that yet – one small project, and an Arduino open source electronics prototyping platform “shield” from Adafruit Industries called the “Adafruit Proto Shield for Arduino kit – it’s on sale currently (March 4, 2010) and a really useful board if you have an Arduino NG, Diecimila, or Duemilanove model of the Arduino open source platform.
Anyway, back to the Meggy Jr. RGB! It’s an open source LED Matrix game development kit based on the same AVR microcontroller family that is at the heart of the Arduino platform. As a result, you can program the Meggy Jr. RGB with the Arduino software and the specifics of the Meggy Jr. RGB are made easier by a high-level library that EMSL provides.
The build was pretty straightforward thanks to excellent instructions included with the project, but it did take Geek a number of hours (3?) to complete the whole thing. We took a break for lunch, but other than that he worked straight through on it and really wanted to get it done and start programming it. Some younger kids may not have the patience to complete this big of a project. There are some pins that are pretty close together and I had to guide Geek on how to steady his hands and how to put minimal solder onto the joints (got a few solder bridges, but we were able to clean them up ok).
The only criticism I have for the Meggy Jr. RGB kit is that we got the “Super Kit” version (which you want – not having handles/covers means your fingertips can (and do!) short out wires and cause it to not function properly and the AC adaptor is a really good idea to keep endless battery use down) and had a problem with the switches and the precision of the laser cut holes in the handles/covers. The laser cut classic handle set is cut so tightly that we had a problem with switches that were not exactly positioned hanging up on the top handle and preventing it from working properly. The holes for the switches should be slightly larger to provide a little more “give” in the build, and the instructions should be very clear about the need to get the switches pressed down completely against the circuit board so that their relative position and orientation is perfect. I’ve passed this on to EMSL.
Geek has had a great time programming games, and modifying some of the many (!) games you can find on the EMSL wiki. It’s surprising just how fun of a game you can make with and 8×8 RGB LED matrix, 8 additional LEDs and sound generation ability. The 8×8 grid are RGB LEDs and you can control their color quite easily so there is quite a bit of variation possible.
After modifying the enhanced version of the default starter game that he found on the wiki, he started his own – the game of “Go” which is actually quite challenging to do at this scale. Some clever tricks and he has something interesting, though not yet complete.
In any case, if you have a capable kid who likes to solder and has some computer programming skills (basic “C” style syntax, but mostly just simple stuff), then this is quite a fun project – build it and then create games to play on it!