
[Alex] from Tinkerlog has revisited an old project with Synchronizing Fireflies NG. Fascinated by how fireflies blink at same rate and synchronize with each other, he built a digital version. Each board has an RGB LED and a phototransistor or photoresistor. A ping-pong ball is used as a diffuser. The blink rate is controlled by an ATtiny13v. The board power can be daisy chained, but each firefly mote operates independently of the others. The microcontroller has a fixed flash rate and monitors for other flashes. It attempts to sync by flashing earlier. The color of the LED expresses how satisfied the firefly is with its current sync. You can see a video of eight fireflies attempting to self organize embedded below.
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RGB LED Cylinder
[Dave Clausen] from NYC Resistor sent in his open source RGB LED cylinder. We have seen many cubes in the past (even one that display low-res 3D video) so a cylinder is certainly a new concept and the RGB LEDs are a nice upgrade. The LEDs are wired in a 5-way multiplexed grid using four TLC5940NTs (16 channel LED drivers with internal PWM hardware) so each light is individually addressable. The best thing about this project, of course, is that he has source and EAGLE schematics availbale for download and both are licensed under Creative Commons.
[via NYC Resistor]
Tom’s RGB Mood Lamp

[Tom] has been refining a board that drives a high power RGB LED for applications like this moodlight. It’s based around an ATmega8 microcontroller. The goal was to make an RGB LED easy to work with: It can cycle between colors in standalone mode. You can control it via a serial interface. It also has a pin header to hooking up three potentiometers for manual color mixing. Boards aren’t available yet, but he’s already posted a build tutorial. The board looks straightforward enough that it shouldn’t be too hard to layout if you really want to.
How-To: Make An RGB Combination Door Lock (Part 2)

In part 1 we showed you how to build your own prototype RGB keypad. Today we’ll show off some new ideas we worked on to create the project and turn it from prototype to fully functional battle station er door lock.
Continue reading “How-To: Make An RGB Combination Door Lock (Part 2)”
RGB Etched Box
[youtube=http://www.youtube.com/watch?v=KG4PWZyR4Sk&hl=en]
[Dine909] brings us this simple glowing box made out of five etched PCBs. The PCBs control RGB LEDs inside the box, which is also filled with clear glass beads. The four walls are connected to a base controller board that has a Cypress PSoC chip for color mixing. There’s no writeup, and even though it looks a lot like the Lament Configuration, it should be a lot easier to build; any transportation to other dimensions it provides will be strictly figurative.
[via ladyada]
How-To: Make An RGB Combination Door Lock (Part 1)

Part 2 can be found here
Putting a custom designed electronic lock on your space seems like a geek right of passage. For our latest workspace, we decided to skip the boring numbered keypad and build a custom RGB backlit keypad powered by an Arduino. Instead of typing in numbers, your password is a unique set of colors. In today’s How-To, we’ll show you how to build your own and give you the code to make it all work.
Continue reading “How-To: Make An RGB Combination Door Lock (Part 1)”
Fnordlicht: RGB Mixing LED Light

While [Will] goes and hides in his offshore datashelter, Hack-A-Day is happy to welcome back our veteran foreign correspondent [fbz]. She promises future posts will have far less ‘German by example’. -[Eliot]
The Fnordlicht is a color mixing LED platform with free hardware schematics and open source firmware initially started by [fd0]. The system is dynamically controllable (via RS-485) and can also work as a standalone with pre-loaded color mixing. I have one of these soldered up and working at home; the circuits come in a stack of three boards with an optional serial level shifter board add-on. There are project pages in German about the Fnordlicht as well, which include some photos of the first prototype. Full kits (“Fnordlicht Bausatz” means “Fnordlicht kit”) and printed circuit boards (“Fnordlicht Platinensatz ohne Bauteile” means “Fnordlicht circuit board set without parts”) can be purchased from their shop, but be sure to ask them first about shipping prices to your location. I love this project, I fire it up and stick it in a corner of my hack room to add some color-changing atmosphere.
A while ago [Eliot] covered the MoMolight, a color changing led project controlled by the colors playing on your monitor.