I would use configuration 2 here:
http://cdn.shopify.com/s/files/1/0038/9 ... 1262060842
Configure for 3.3 V logic by soldering a wire across the 3.3 select pads -OR- if you need to switch back and forth from 5V to 3.3V logic then solder on the 3 header pins and install a berg jumper. For use with the RPi you must select 3.3V.
TX to RPi RX (GPIO pin 10)
RX to RPi TX (GPIO pin 8)
GND to GND (GPIO pin 25)
Normally you would not connect the 5V from the USB BUB to anything.
Go here for my RPi writeup. Basic config, Serial Port add-on etc:
http://blackeagle12.net/Comp/RPi/Rpi.html Click contact icon then world icon --->