CompactPCI Serial parallel CompactPCI comprises another specification called PICMG 2.30 CompactPCI PlusIO. This is why CompactPCI Serial and CompactPCI PlusIO as a whole were also called CompactPCI Plus. PICMG's first working title of CompactPCI Serial was CPLUS.0. (See also #Compatibility and Migration.) CompactPCI Serial backplanes and chassis are developed by Schroff, Elmа, and Pixus Technologies companies, as for the CompactPCI Serial board level electronics – they are developed by MEN Mikro Elektronik, Fastwel, EKF, Emerson Embedded Computing, ADLINK, and Kontron. Fast serial point-to-point connections have become the state-of-the-art technology and are gradually replacing the classic bus architecture in computers. The CompactPCI standard
Parallel port later than Windows 95/98 prevent user programs from directly writing to or reading from the LPT without additional software (kernel extensions). Current CNC Milling Machines also often make use of the parallel port to directly control the machine's motors and attachments. Traditionally IBM PC systems have allocated their first three parallel ports according to the configuration in the table below (if all three printer ports exist). If there is an unused slot, the port addresses of the others are moved up. (For example, if a port at 0x3BC does not exist, the port at 0x378 will then become the first