You should put the board in dfu mode first. Read the instructions carefully
Does the fact that I'm on the Uno R3 (which has an ATmega328) put me in a different situation from this guide which focuses on the ATmega8U2? I'm reading the instructions very carefully and nothing points me towards a solution that allows me to get the thing into DFU mode. This article looked promising: http://academic.cleardefinition.com/2012/07/31/using-dfu-programmer-with-an-arduino-uno-r3/ but I'm still utterly confused. Also, this thread http://arduino.cc/forum/index.php/topic,92148.0.html seems to be aiming at a solution for a similar problem but doesn't appear to arrive at one. Whenever I tap the appropriate pins that should cause it to reset simply restart the board and it goes back to blinking. I hope I'm not missing anything glaring. Thanks
I've installed FLIP, and I can see how it should normally work, however since the board isn't communicating with the computer at all, I don't think I can do much from here. The guide you linked presupposes that the computer at least recognizes it as an unknown device or that you're trying to wipe the existing firmware after having been able to use the board successfully in the past. For clarity I'm on the Uno R3. Should I consider just buying a new board, or am I missing something entirely? Thanks
I've got the same exact issue, but with the Uno. There is no indication whatsoever that the board is interacting with the computer; it's not showing up in Device Manager anywhere or telling me that there's an unknown device. I'm on Windows 7, and I'm also having issues getting it to talk to the Mac. When I plug the board into any USB port on any of my machines, the green light shows that the board has power and it runs the default Blink sketch but I have no way of uploading sketches or updating the driver from the computer. I've tried hitting restart on the board, plugging it into all different ports, and tried multiple USB cables. I've scoured the internet for solutions to this problem but many solutions seem to occur through the Device Manager, but that doesn't seem to be possible in my case.