How to develop self-develop input device for u3d?

we have develop a device for 3d position and coordination which trans the data using usb port. How can I receive the data in u3d ? I have receive the data using c++,but I don’t know how to receive the data in u3d. can anyone help me?thanks,waiting for your answer~~~:shock:

I presume that you have a DLL file.

Check out the documentation.