On Saturday afternoon I started working on the Meggy Jr RGB kit. When assembled it turns into a portable game platform which you can code to. It’s about the same size as the original Game Boy Advance and uses an 8×8 RGB LED matrix. Here is the final assembly, with optional acrylic cover.

It will take about two hours for an experienced kit builder to put together. What you don’t see, under the LED matrix, are a handful of transistors, the two LED driver chips, and some other components (caps, resistors, etc). Those parts probably take the most amount of time, due to the number of pins involved, and the fact that you have to bend back the transistors (like the one in the upper left of the photo).

Toward the upper right is the Atmel ATMEGA168, with an Arduino bootloader (I believe). This allows you to program the system just like any other Arduino board, which is really cool. They even provide some libraries for making interaction with the RGB matrix easier. I haven’t tried coding anything yet, but it’s a big plus for this system. (That header to the upper-right is where you connect your programming cable.)

A couple of hints for those considering this kit:

• Get the acrylic cover kit. It makes for a much more usable final product. If you don’t have a cover you’ll be poking yourself on the solder points. The cover does both the front and back (the 3 AAA battery pack velcros to center back of kit).
• Be careful when installing the upper yellow LEDs. They must be perfectly aligned to fit into the cover. I had to desolder many of them, fit the cover, and then resolder. It’s probably a good idea to test-fit the cover over those LEDs while you are installing them. (While you still have the protective paper on the acrylic.
• There is a big fat electrolytic capacitor under the LED matix, right below the left yellow LEDs at the top. It is a huge pain the in ass, as it butts into the bottom of the matix, making it harder to install. It’s also right near another cap, making it harder to shift around. Do yourself a favor and give it some “slack” when installing it; or don’t solder both leads until the matix is in place. It’s a very tight fit and I hope that V2 uses either a different cap, or a different placement. Away from the edge would be better.

Again, the matix is RGB, so you can get almost any color you want, per LED. Here is what the POST looks like:

Hopefully I’ll have some time in the near future to write some games or other programs for it.

On the Peggy front, 200 LEDs installed … 400 to go.

My recommendation on this one is get some construction adhesive (I use Loctite PowerGrab, in the pressurized can) and put a dab on each LED, then seat the LED. Let a batch dry, flip, solder, and repeat. Some of them will fall out (if you don’t use enough adhesive) but it’s easier than trying to hold onto the LED while soldering it. If you insert, bend leads, solder, repeat, it will take forever. Try to do big batches at once.