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I think I broke my Arduino Uno as I was playing with it. I connected an ultrasonic range finder to it and uploaded a sketch to it. It was working fine until I accidentally touched the ICSP headers for the USB interface (the pins near the USB port). Now,everything is still working but my computer cannot detect it and it does not show up in the device manager or the IDE. Please tell me if it is broken and how to fix it.
BTW, I just bought it and just started using it after another Arduino had the same problem.