In the link below, at number four of the steps (about sparkfun ft232RL serial to usb), it says to connect to the board the VCC and Ground so that i can supply 5 volt from my usb to my board.
If i have an external supply for the board, and want to connect the usb to serial converter just to upload a sketch, the VCC and GRND connections are needed?
I have a plug to 220Volts with a regulator 7805, and all the circuit is powered by it. Whenever i want to change the sketch to my atmega or even to use the serial monitor, the only wires needed are the TXD and RXD?