Alright I have been stuck on the same problem for months. I have a Xbee shield from ladyada and configured them using xctu. I take out my atmega chip then plug them in. They now talk to eachother. From here I still have everything hooked up and put the chip back in and upload my sketch to the arduino. From here I switch to my 9v source not USB... Then nothing happens I have code in other post by me and am sure it's not the code( I have tried multiple codes). Any help? I really need to fix this.