USB and RS232 ("Serial") devices run under similar specifications, although the connectors and cables used are totally different. If you want to connect a USB device to a serial port, this would have to be done using special equipment, and no other choice is really left to you, unless you want to go ahead and buy a USB peripheral attachment for your computer's motherboard. If you have no space in your motherboard left for such an attachment, you really cannot do anything other than get yourself a USB-to-RS232 converter--also known as a USB-to-Serial converter.
Step 1
Turn on your computer normally and let it boot up on its own. Do not do anything until your computer is fully booted.
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Step 2
Attach the serial end of the converter to your computer's port and wait for your computer to detect it and install the necessary drivers. If your converter is simply a cable or some sort of simple device with just a USB receiver on one end and a serial connector on the other, then you might not have to wait for detection.
Step 3
Plug in a USB cable to the USB end of your converter.
Step 4
On the other end of your USB cable, plug the USB device in which you intended to use on your computer. Wait a while and see if the computer detects it.
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