I'm on mac osx working with an Arduino Uno R2 I got from a friend. While uploading code to the Uno yesterday, I accidentally tapped the positive wire from my 12V battery pack to the 5V Uno output. This happened while it was connected to my mac through usb and my mac turned right off afterwards. When I booted everything back up, I wasn't able to upload code to the Uno any more. I did a little troubleshooting and I noticed that pin13 doesn't blink anymore when I restart the Uno. Anyone know what's going on and whether there's a fix???? Thanks
Does the power LED come on, so you know the mac USB is still providing power?
Try the Serial Loopback test to start, see if you took out the USB/Serial chip.
If that passes, then likely you need to just replace the ATMega328. Outputs are limited to 6V Absolute Max, 12v will break the output pin and often more.
Here's one source for a blank part and for a bootloaded part, there are others.
vectorcpp:
Thanks for the guidance, CrossRoads. I guess I'm going to have to grab another Arduino
I can sympathize, I've blown an Atmega328 in similar fashion. Taught me to trim down the legs of components plugged into a breadboard so they don't stick out.
