If your laptop or computer does not have a RS232 serial port then you can still use the software. You will need to purchase a "USB to Serial Adapter". These are inexpensive devices that emulate a RS232 DB9 male serial port. Typical cost is usually from 10-15 USD. More expensive models are avalaible but will not provide any additional functionality. Usually the cheapest versions work the best. Sometimes the really expensive ones have been known to have problems.