Apple iPod Shuffle Headphone Remote Emulation
You may have seen the circuit board that is built into the headphones of the Apple iPod Shuffle. David Carne did a great job of reverse engineering what the iPod Shuffle Headphone circuit actually does. He also went as far as to emulate the circuit using a microcontroller on a bread board. There is an interesting frequency that is used at startup so that the iPod can determine what type