Is there a way to have a USB connection to a Duemilanove, but get the power by connecting a different 5V power supply to 5V on Duemilanove? In other words, can I disable auto power selection?
I want the convenience of USB programming, but dont want the power to come from the PC.
Alternatively, can I do this by using a USB TTL-232 cable TTL-232R 3.3V (from adafruit.com)? http://www.adafruit.com/index.php?main_page=product_info&products_id=70. If I do this, which pins of the TTL cable must be connected to which pins of the Duemilanove?
Duemilanove GND and 5V would come from an alternate power source.