peripheral devices and ports

8/2/2019 Peripheral Devices and Ports

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Engr:SajidaIntroduction to computing

Peripheral devices

A computer device that is not part ofthe essential computer i.e., the memoryand microprocessor

Computer devices that are connected to

the computers motherboard externallyand internally

A special designed software is required

to instruct the computer how to usethese devices


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such as printer, scanner, keyboard, mouse, tape

device, microphonePeripheral devices can be external -- such as a mouse

,keyboard, printer monitor ,scanner etc

or internal, such as a CD-ROM drive , CD-R drivemodem


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Peripheral devices can be classified according totheir functions.

Input

Input devices are the type of the computer devicesthat are used to provide the control signals to thecomputer. Keyboard and the Mouse are theexamples of the input devices.

OutputOutput devices are the devices that are used todisplay the results. Printer, scanner, speaker and themonitor are the examples of the output devices.

Storage

A storage device is a device that is used to store theinformation such as hard disk drive, flash drive,floppy disk and the tape drive.


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Other examples are

Trackballs

Modem

Scanners

Computer projectorprinter


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Modem transfers data from one computer toanother computer over telephone lines

Scanners converts text or images on paperdocuments into an electronic format that thecomputer can display ,print and store

Projector generates a large image of whats onthe computer screen suitable for conference&lecture presentation


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Ports

An interface on a computer to connect a

device

most system units feature exterior connectorsor sockets called ports in which hardware

devices are pluggedEach port is connected to the appropriate buson the motherboard so that devices pluggedinto each port can communicate with the CPU

without these ports system could not bootproperly and interaction of software on thesystem is unable


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Internally, there are several ports for

connecting disk drives , display screens, and

keyboards.

Externally, personal computers have ports for

connecting modems, printers, mice, and other

peripheral devices


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Standard computer ports

Mouse and keyboard ports

Two USB ports

Serial ports

Parallel ports

Audio ports

Network port

Modem port

Monitor port


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Standard Computer Ports


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Mouse and keyboard port

Accepts the key board and mouse plugs

This port uses a PS/2 connector

A mini plug containing 6 pins.

Developed by IBM for connecting the keyboard

and mouse.


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USB ports

Are used to connect USB devices to the computer

Most new PCs come with two USB ports

becoming the most common port for connecting

device peripherals to personal computers.

accept any number of devices including cameras and

joysticks


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Serial portSerial port can transmit data one bit at

one timeThey use inexpensive cables and they can

be send data over the long distances

Serial ports can be used for such devicesas keyboards, mice and modems

Serial ports have 9 or 25 pin connectors


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Serial communication


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Parallel portsOne byte (8 bits) at one time

Making data transfer more faster than those throughserial ports

Require more expensive cables

Used to connect printer and scanners to the PC

Types areECP (extended capabilities ports )and

EPP (enhanced parallel port)


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Parallel Communications


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Audio ports

There are three audio ports on modern computer

Network Port

Used to connect a PC to a local area network

Most network cards contain a port that accepts aRJ45 connector


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Modem port & phone port

Used to connect a modem card to phone portThe most common use of modem is Internet

access

Monitor port

Connected directly on the motherboard or

expansion card

Used to connect a monitor to PC


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Expansion Ports

These ports allow the connection of specialdevices through the computers expansion bus

SCSI (small computer system Interface )

IEEE1394(Firewire)MIDI (musical instrument digital interface )


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Small Computer System Interface

Parallel Interface Standard used by most Apple

Macintosh and PCsHigh speed parallel port generally used toconnect disk drives, printer or scanners

SCSI interfaces provide for faster datatransmission rates (up to 80 megabytes persecond) than standard serial and parallel ports

Many devices can be attached to a single SCSIport, so that SCSI is really an I/O bus ratherthan simply an interface


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A single SCSI adapter extends the bus outsidethe computer by way of a cable

Like an extension cord for a data busBy plugging one extension cord into the other,one SCSI device is attached to the another toform a chain

When devices are connected in this way andplugged into a single port ,they are called adaisy chain


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Musical instrument digital interface

Used to connect MIDI device to he computer

MIDI devices includes musical keyboards and other

instruments to compose music and stored

electronically

MIDI system are widely used in recording andperforming music to control settings for light system

drum machines, amplification and more

peripheral devices and ports

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