I have a old piece of junk of a computer, and i was thinking maybe i can start experimenting with using the usb port in it as a source of voltage or power. It would be pretty cool to turn on a circuit by plugging into a usb port. The problem is that i have no idea what the 3000 pins on the usb jack do. If anyone had some kind of short explanation or a link to a site that gave you a general overview, I would really appreciate it.
Well i already did, but 95% of the results have to do with flash drives and other usb devices, and the other 5% which actually deal with circuits assume you know too much. I didn't really find an introductory site, so i asked.