IEEE 1284

Standard for parallel peripheral interfaces, known as the Centronics port An IEEE 1284 36-pin male micro ribbon printer cable connection. The computer side of this cable normally uses a DB-25 male connector. IEEE 1284, also known as the Centronics port, is a standard that defines bi-directional parallel communications between computers and other devices, with a theoretical maximum throughput of 4 MB/s. It was originally developed in the 1970s by Centronics for use with dot matrix printers before being formally standardized by the IEEE in March 1994. The standard defines five operating modes Compatibility Mode, Nibble Mode, Byte Mode, Enhanced Parallel Port (EPP), and Extended Capability Port (ECP) and three connector types. It supports a variety of peripheral devices including printers, scanners, tape drives, and hard disks. Since its release, the parallel interface has been largely displaced by local area network interfaces and USB 2.0. History An IEEE 1284 36-pin female on a circuit board In the 1970s, Centronics developed a parallel connector for their dot matrix printers that soon became a de facto standard. The original port design was send-only, allowing 8 bits of data to be