Here’s a unique way to program an Arduino chip: using your computer’s sound card! Chris from the hobby-roboter forum provides the details on this amazing hack in his forum post. The process simply requires the Atmega168 to be programmed with Chris’ special audio bootloader. The whole project requires only the addition of three resistors, two caps, an LED, audio jack and reset switch. Thereafter programs are developed in the Arduino IDE, then the hex is uploaded to the Audioino via Chris’ Java program (contained in the source code zipped file.)
This is a really cool hack, reminding some of us how we loaded programs into the CPU memory using cassette recorders back in the day.