I found a work-around by searching the forums, but I'm looking for a better solution.
The problem. My Uno R3 won't boot in stand-alone mode using only a 1000ma wall wart power supply.
The Uno will boot fine from USB or 9V battery (w/adapter cable). I did a search and it appears to be an issue with the voltage levels coming from the wall wart.
My work-around it to boot from USB power, then plug in wall wart, then disconnect USB.
Anyone have a solution on how to boot from the wall wart PS only?