LED Based Fireflies

This project is about a LED based asynchronous fireflies which were used as a Christmas project. The aim of the project was to make a low-power, low parts count module that can sense when it’s dark and then mimic the blinking patterns accordingly. For the project he’s using an Atiny85 along with an external clock which was programmed by setting external fuse-bits which is a conventional way to set clock source or frequency in almost all type of AVR’s A good things about the project is, it’s completely hand-made and that include the making PCB’s at home. To etch the PCB cupric chloride was used which is one of the quickest process to etch PCB but the time might depends upon the temperature. Also, to transfer the PCB design, from the computer to PCB, tone transfer method was used which is very impressive. An impressive project overall, but the complexity can be reduced if one uses in internal clock. Continue reading

Very simple low power fireflies based on Attiny micros

attiny led based fireflies

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. Continue reading