Blinkie prototyping, etc

[johnridley]

I'm supposed to be coming up with a new blinkie design for Duckon 20, so I picked up an Arduino LoLShield. This is a 9x14 grid of LEDs, charlieplexed, the max that an Arduino board can drive without extra driver chips. I figured it'd be good for prototyping blinkie patterns, etc before actually building anything.

I just got it together and ran the basic test and then the "game of life" demo.

Heck, this is a pretty cool blinkie just as it stands. Of course, $55 ($30 for the Arduino, $25 for the LoLShield) is a bit much for a blinkie, but over half of that is the Arduino, which is highly programmable and can do about anything. Some people may go for it, or may already have an Arduino. It does take some patience to solder up 126 LEDs though.

No, I'm not planning to make this the next blinkie, but I think it's very likely that it'll be what *I* am wearing around cons, assuming that I'm not wearing the next blinkie for advertising.

Comments

[dave-ifversen.livejournal.com]

What kind of power does the Arduino and LoLShield take? (Can you actually wear it as a blinkie without dragging a handcart full of batteries behind you? Seems like 126 LEDs would pull down the battery pretty fast...)

I've never played with the Arduino - sounds interesting enough that it might be fun to give it a try.

[johnridley.livejournal.com]

Well, it's heavily multiplexed so only 9 LEDs are ever on at once. But honestly, if I ever do a blinkie with a large matrix of LEDs, I'm going to use an external AA pack. It's not any more expensive, and it's ridiculous the amount of time you don't get out of 4 LR44s. The 8x16 2dkit, for instance, lasts about an hour on a set of batteries.

I am thinking about a really tiny blinkie, and for that I'm thinking CR2032. The capacity is about the same as a set of LR44s, the cost is still really low, the space requirements are less, and you can get good, easily solderable holders for cheap.

Arduino is nice because the CPU is pretty powerful and the software ecosphere is gigantic. Whether you want to run a matrix of LEDs, a bank of 32 servo motors or whatever, there's a library that will get you halfway there before you even get started.

In reality a full arduino wouldn't be necessary here; all that's really needed is the CPU, which are about $4 in single quantity. The rest of the arduino is the board, USB controller and other nicities. You could just design the matrix board with a CPU socket on one end, add maybe a switch and you'd be done. A simple header is all that would be needed for in-circuit programming, then anyone who wanted to change their patterns or whatever only needs to buy a $5 USB adapter off eBay.