simple Rockwell GPS serial port reader

I'd like to write a program that can make sense of the Rockwell binary ouputs from my Earthmate serial GPS when connected to my MIPS HPC PRO .
I am downloading the SDK for Visual C/Basic from the developers section.
I am rather lost although I can code in both C and Visual Basic.
How should I proceed from here?

Check out the code for the Linux program, gpsd. It controls gps devices on Linux, including the serial Earthmate. Although Linux is vastly different from CE, you could probably figure out how they control the devices. Most likely, you can find the answer to your output question in there, as I believe that all proper gpl projects are well commented.