COMPUTER PORTS

The Motherboard of a computer has many I/O sockets that are connected to the ports and interfaces found on the rear side of a computer. The external devices can be connected to the ports and interfaces. The various types of ports are given below :

1. Parallel Port
   • A parallel port transmits 8 bits of a byte of data in parallel as it contains eight or more data lines for control of I/O devices.
   • This consists of 25 holes.
   • It is used for transmitting fast data over short distances because interference among multiple signals limits the cable to relatively short distances.
   • It is commonly used to connect the printer to a computer.
   • However, USB port is mostly used today to connect printers to computer systems.





Parallel Port



2. Serial Port
   • A serial port transmits one bit of a byte at a time as a single stream of bits.
   • It is meant for transmitting slow data over long distances.
   • Communication over a phone system is an example of serial communication.
   • A serial port connects a variety of devices such as modems, scanners, barcode readers and device control circuits.
   • Today, USB port is used instead of the serial port.





Serial Port



3. PS/2 Port
   • It consists of six pins in a small and round shaped socket.
   • It is one of the serial port connectors used to plug mouse and keyboards into a personal computer.
   • The purple port is for the keyboard and the green port is for the mouse
   • However, USB port is mostly used today to connect the keyboard and the mouse to the computer system.





PS/2



4. Universal Serial Bus [USB] Port
   • USB port is the most popular port used to connect up to 127 peripheral devices such as digital camera, speaker, scanner, printer, plotter, modem, joystick, pen drive, etc.
   • USB 3.0 is the third major version of the Universal Serial Bus (USB) standard to connect computers with other electronic gadgets
   • USB 3.0 can transfer data up to 5 Giga byte/second.
   • USB3.1 and USB 3.2 are also released.
   • USB permits Plug and Play – i.e. it allows us to install device drivers as and when the devices are plugged on.





USB



5. Small Computer System Interface [SCSI] Port
   • SCSI port allows data transmission in a 'daisy chain' to up to 7 devices at a speed (32 bits at a time) much higher than serial and parallel ports.
   • The devices that may be connected to SCSI ports are hard-disk drives, CD-ROM drives, scanners, backup units, network adapters etc.
   • In daisy chain several devices are connected in series.
   • If data has to reach the seventh device then it needs to go through, all the six devices first.





SCSI



6. Fire Wire [IEEE 1394] Port
   • Fire Wire port is a relatively a new technology for high speed data communication. It is extremely fast with Data Transfer Rate up to 400 Mb/sec.
   • The need of this arose due to large audio and video data movement from multimedia devices.
   • The devices connected via Fire Wire Port are Video Camera, External Hard Disk Drives, External CD/DVD Drives.
   • Microsoft has developed device drivers to support IEEE1394 in all the versions after Windows 95. Linux also supports this port.





IEEE 1394



7. High Definition Multimedia Interface [HDMI]
   • This port can be seen especially in laptops.
   • HDMI is an audio/video interface which transfers the uncompressed video and audio data from a video controller, to a compatible computer monitor, LCD projector, digital television etc.





HDMI



8. Video port - VGA [Video Graphics Adaptor]
   • VGA is used to connect a monitor or any display device like LCD projector.
   • This is also called the Graphic Port.
   • The port consists of 15 holes.





VGA



9. Audio Ports/ Jacks
   • This is used to connect sound speakers, microphone and headphones.
     1. Blue – Line In
     2. Green – Line Out, Head Phone
     3. Pink – Microphone





Audio Jacks



10. RJ-45 Port
    • This port connects computer of a computer network to the network router, network switch.





RJ-45

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