I convert USB outputs from a PC to serial for connection to an autopilot
, no problem, but must use an active converter (w/software) so the computer can recognize the device on the USB bus. The actual data is not changed. You can buy cheap
USB to serial and USB to PS2 adapters, but they usually don't work for the above reason. The USB GPS runs on 5V, and the connection diagram is here:
USB pinout and signals @ pinouts.ru
On the Raymarine. Orange is Rx Data +, Yel is Rx Data -
To upload settings or firmware updates to the GPS, you'll need to connect it to a PC.
If you haven't bought the GPS already, I'd suggest the Garmin