Fireflies are interesting creatures that glow in dark due to biochemical reactions. They come in special season time and stay for a really short time period (probably while mating). Anyway if you enjoy the show of fireflies and would like to make them stay longer then you should consider making artificial swarm. Karl decided to experiment with simple low power solution.

The circuit is based on Attiny13a microcontroller which has 8 legs. It is powered from CR2032 coin-cell battery. Chip carries single green LED and 1MOhm resistor. This resistor is connected parallel to LED. This resistor is necessary because LED also is used as light sensor. Fireflies most of the times are in sleep mode and occasionally checks ambient light. If it is dark enough, they stat flashing. I would expect some sort of swarm behavior when fireflies detect near by pattern and so adjust flashing that would create multiple flashing patterns. Anyway this is great weekend project to do with kids.

Michael likes his vintage organ KORG CX-3. It sounds good and keyboard feels right to play. But in early 70s there were no MIDI. But today almost any electronic music instrument comes with MIDI or other output interface. He decided to add a MIDI to CX-3 organ. For getting data you normally need to detect each key pressed. Luckily Michael found a great source on Internet with schematics where couple ICs are connected to keys that generate serial data stream. This gave him an access to keys by using couple of wires.

Next step is a midi interface. Attiny2313 seemed to be enough for generating MIDI. A home made PCB looks really great next to vintage organ schematic and it does job well. To see how to generate MIDI on AVR check out this resource on AVRfreaks.

We usually expect clock to tick regularly. In time we start to ignore the sound of ticking arrow. But not with this Vetinari clock. It ticks irregularly. Akafugu built Attiny25 based clock kit to modify it so it would tick randomly but still keep accurate time.

He provides detailed steps on how to assemble it. Electronics can be connected to standard quartz clock.

Generating VGA signals on AVR microcontrollers is possible, but it takes heavy load and there is not much resources left to do other intensive tasks. And there is no talk about higher resolution images. If you want to do something amazing with VGA and stick with AVR then it is better to use a dedicated hardware for generating video signals. uVGA is a great choice for this. Andrew has been playing with uVGA II which takes all graphics drawing load. Leaving controller free to do what ever you want. These include an Audio Player, Theme Manager and Window Factory which is used to create new windows.

He caught an idea to make a windows manager similar to PC. For user input he used mouse. He collected several applications to play with. The code still needs polishing in order to get rid of some blurring during windows transition, but over all program model looks really promising and fun to try.