Solved: Chicken-Egg-Problem with AVR DIY-Programmer
There are several projects to build an AVR-Programmer. But they all have the same problem. How to program an AVR-Microcontroller without a Programmer. What can You do? For example use your Sound Card to solve this issue.
We want to build the USBtiny Programmer from http://dicks.home.xs4all.nl/avr/usbtiny/index.html
The parts required are readily available and the circuit is easy to build.
Uploading the firmware
Connect your circuit to the headphone jack, turn volume up to 100%, activate the reset and press the play button.