What is a parallel port and how does it work?
PARALLEL PORT ABCs DB25 connector with an 8 bit data bus which is more popularly used for computer printers while is still used for other devices. The standard length of Printer Parallel cables is a maximum of 15 feet; although there are 50 foot cables, it is not recommended that these cables be used as it can create poor connection and data signals. TYPES OF PARALLEL PORTS Unidirectional – 4-bit standard port which by factory default did not have the capability of transferring data both ways. Bi-directional – 8-bit standard port which was released with the introduction of the PS/2 port in 1987 by IBM and are still found in computers today. The Bi-directional port is cable of sending 8-bits input and output. Today, on multifunction printers, this port can be referred to as a bi-directional, Centronics, PS/2 type or standard port. EPP – The Enhanced Parallel Port (EPP) was developed in 1991 by Intel, Xircom and Zenith Data Systems and operates close to ISA bus speed and can achieve tran
This interface is found on the back of older PCs and is used for connecting external devices such as printers or a scanners. It uses a 25-pin connector (DB-25) and is rather large compared to most new interfaces. The parallel port is sometimes called a Centronics interface, since Centronics was the company that designed the original parallel port standard. It is sometimes also referred to as a printer port because the printer is the device most commonly attached to the parallel port. Data flows in one direction only, from the computer to the printer or other device. In addition to eight parallel data lines, other lines are used to read status information and send control signals.
