What is parallel port – The parallel port is actually an external interface commonly found in older PCs that were used from the late 1980s through the early 2000s. It was used to connect to peripheral devices such as printers and external storage devices.
What is parallel port?
Later, USB was used in its place, which provides smaller connections and in this you also get a very fast data transfer rate. Although these parallel ports are a hallmark of older computer technology – they used to be very large in size and their speed was slow. A standard parallel port connector has a total of 25 pins in two rows, surrounded by a metal casing.
It’s just under an inch thick and has two screw-in connectors that help the cable stay in place. Parallel port cables used for printing have a very large 36-pin “Centronics 36” connector that connects to a printer. Talking about the original parallel port standard, it used to be unidirectional, and it could transmit data at a maximum speed of 150 Kbps.
As printers became more common, it became necessary to provide bidirectional communication as well as increase the speed of the connection. Instead send a “print” command to a PC and expect the print job to succeed, while bidirectional capability allows the printer to send messages back to the PC, such as “ready,” “printing,” and “done.” The faster transmission speed enables parallel ports to be used for other purposes, such as external storage devices, for example the Iomega Zip drive.
IEEE 1284 – This parallel port was later standardized by the IEEE as “IEEE 1284”. This standard defined several new versions of the parallel port, including the Enhanced Parallel Port (EPP) and the Extended Capabilities Port (ECP). In this EPP can transmit data up to 16 Mbps (2 MB/s). While ECP has a data transfer rate of around 20 Mbps to 2.5 Mb/s, that too via an ISA bus.
You may be aware that the first version of USB was not much faster than a parallel port, while it did see several other improvements, such as a smaller connector and the ability to use electrical current to send a voltage, allowing an external The device can receive power. It was also hot-swappable, meaning that a USB device could be safely connected or disconnected while the computer was running.
Thus, connecting or disconnecting a peripheral, that too via IEEE 1284 connection, can damage the device or the PC. But since the introduction of USB 2.0, which provides data transfer rates of around 480 Mbps, parallel port use has been completely phased out, and with it the IEEE 1284 standard has been lost to computer history.
What is a parallel port?
The parallel port is an external interface commonly found in older PCs. It was used from the late 1980s through the early 2000s to connect peripheral devices such as printers and external storage devices. However, it has been phased out with the introduction of USB.
How does a parallel port differ from USB?
USB replaced the parallel port, offering smaller connections and faster data transfer rates. Parallel ports were larger in size and had slower speeds compared to USB. USB also provided the convenience of hot-swapping devices without the risk of damaging them.
What does a standard parallel port connector look like?
A typical parallel port connector has 25 pins arranged in two rows, enclosed in a metal casing. Its thickness is just under an inch and it has two screw-in connectors to secure the cable.
What type of connector is used for printing with a parallel port?
For printing, parallel port cables use a large 36-pin “Centronics 36” connector, which connects to the printer.
What were the limitations of the original parallel port?
The original parallel port was unidirectional, meaning it could only transmit data. Its maximum speed was 150 Kbps, which was relatively slow.
Why was bidirectional communication and increased speed necessary for parallel ports?
As printers became more common, bidirectional communication and higher speeds were required. Bidirectional capability allowed printers to send status messages back to the PC, and faster speeds enabled parallel ports to be used for other purposes, such as external storage devices.
What is IEEE 1284?
IEEE 1284 is a standard that later standardized the parallel port. It defined various versions of the parallel port, including the Enhanced Parallel Port (EPP) and the Extended Capabilities Port (ECP). These versions offered improved data transfer rates ranging from 16 Mbps to 2.5 Mbps.
Why did USB replace parallel ports?
USB 2.0, with its significantly higher data transfer rates of around 480 Mbps, rendered parallel ports obsolete. USB also introduced smaller connectors, hot-swappability, and the ability to provide power to connected devices.
What are the drawbacks of using a parallel port compared to USB?
Connecting or disconnecting a peripheral device via a parallel port, especially the IEEE 1284 connection, can potentially damage the device or the PC. USB, on the other hand, provides a safer and more convenient method of connecting and disconnecting devices.
Has the use of parallel ports completely disappeared?
Yes, the use of parallel ports has been completely phased out with the popularity of USB. Parallel ports and the IEEE 1284 standard are now part of computer history.
Jay Verma
