I'm working on a project which involves being able to record an electric guitar being played directly from the guitar itself without the need of any extra equipment. My idea is to take the audio analog signal (being produced by the guitar pick-ups) and have it saved onto a USB stick that is plugged into the guitar. I've done a bit of research online, and so far I understand that I will have to have an A/D converter before I can save to audio signal to a USB. I am stuck in understanding how to get the digital signal (once converted) to be saved onto the USB. My idea also involves a switch, in which will toggle on/off when to record - so when it's on, it starts saving the data, and when it turns off again, it finishes recording.
Basically; how to record electrical signal onto a USB.