Why does PlasmaCAM connect to the computer via the parallel port?
At this time, the parallel port is the most reliable and standard form of communication available for connecting a PC to critical equipment. This is why most medical and CNC equipment still use the parallel port. Though newer forms of communication like USB, USB2, Firewire, Ethernet and wireless have been developed, all such technologies use higher frequency signals that are more susceptible to electromagnetic interference. The parallel port cable is also better suited for industrial environments since it is physically stronger, with locking connectors. In a shop environment that involves plasma cutting, the parallel port is the most robust, dependable option.
Computer manufacturers continue to include parallel ports in many new computers. Inexpensive add-on parallel port cards are also available for computers that don't already have ports. Refer to the requirements and recommendations given in the demo video packet before you buy a computer. The PlasmaCAM instruction manual also shows you how to obtain and configure your parallel port.