There are two common ways that GPS devices (internal or external) interface with wintel computers.
Most connect to a COM port (RS232C), either real or virtual. With these devices you can connect with a terminal application (or read and write the COM port in your case). The GPS sends strings out the port that follow the NEMA 0183 standard. Here is an example in VB.NET:
Mapping with a GPS and VB.NET[
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Other devices do not use a COM port, but some other other proprietary means of communication. In this case the manufacturer includes a driver that one of the Windows location APIs can use.
In your case they did the latter.
I think you will find this thread useful.[
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