I have copied some sections from my senior project report
        below for those people who would like to take a look at 
        it or to get some ideas for their projects.


            In my senior project, there are two parts. The first part
        Documents my research and understanding of the Universal Serial
        Bus System (or USB). From it, I have a suggestion of how to
        design a connection using two fiber optic links with the USB 
        port. The second part is to design the interfaces between two
        fiber optic links with an ordinary 9-pin serial port mouse.

            The PDIUSBD11 USB device with serial interface is an useful
        data sheet if you would like to design an adapter between an 
        USB device and serial interface. If you need more information 
        about USB, you might want to visit http://www.usb.org. You will 
        get much more helpful documents from it and discuss what you 
        need there.

            Even though the serial port can transfer data via longer 
        cable than the USB port, its data transfer speed (10-100Kb/s) 
        is much slower than the USB port (1.5Mb/s). However, there is 
        three to five meters length limitation for the USB cable. A 
        user needs a hub to extend the USB cable. If my design of USB 
        with two fiber optic links does work, we will save a lot of 
        money from extending the copper wires and hubs. The advantages 
        of using fiber optic links are the length limitation of a fiber 
        optic link is more than 100 meters and they are cheaper than 
        the regular copper wires.