COMPUTING FUNDAMENTALS

LECTURE 3 : WEEK 3CSC-110-T : FALL 2015

Credit : (2 + 1) / Week

TEXT AND REF. BOOKS2

 Text Book:

 Peter Norton (2011), Introduction to Computers, 7 /e, McGraw-Hill

 Reference Book:

 Gary B (2012), Discovering Computers, 1/e, South Western

 Deborah (2013), Understanding Computers, 14/e, Cengage Learning

 June P & Dan O (2014), New Perspective on Computer, 16/e

MOBILE ALERTKindly Switch Off your Mobile/Cell Phone

OR

Switch it to Silent Mode Please

3

GOOGLE SITE ADDRESS

FOR LECTURE NOTES AND STUDY MATERIAL

DOWNLOAD, PLEASE VISIT :

https://sites.google.com/site/shucsc110/

OR

TYPE “SHUCSC110” & GOOGLE

4

MSc. Telecomm. & Network Management, UK

Masters (CS), Bahria University Khi, Pakistan

Prince2 Project Management (Foundation) Certified

Microsoft Certified Professional (MCP)

Presented by: Flt. Lt. Shujaat H. Butt (R)

INPUT/OUTPUT/STORAGE DEVICES

5

Learning Outcome Input Devices Keyboard, Mouse, Touchscreen etc Output Devices Monitors, Printers etc Storage Devices Hard Disk Drive, Optical Storage etc

7

Input Input is any data and instructions

entered into the memory of a computer

Input Device is any hardware component that allows users to enter data and instructions into a computer

8

Input

Input Device: Keyboard and pointing devices

Pointing devices: Mouse is a pointing device because it allows a user to control a pointer on the screen.

Input In Graphical User Interface (GUI), a

pointer is a small symbol on the screen whose location and shape change as a user moves a pointing device.

A pointing device can select text, graphics and other objects and click buttons, icons, links and menu commands.

9

10

Input Mouse There are 2 types: Mechanical mouse and Optical mouse. Mechanical mouse has a rubber or metal ball on its

underside. You should place a mechanical mouse on a mouse pad. Mouse pad is a rectangular rubber or foam pad that provides

better traction than the top of a desk Optical mouse uses devices that emit and sense light to

detect the mouse’s movement.

Input

Input

13

Input Mouse Optical mouse is

More precise than a mechanical mouse Dose not require cleaning as does a mechanical mouse. Also it is more expensive.

Mouse connects to a computer in several way: By cable through mouse port, USB port and serial port (old). By wireless through IR or Bluetooth.

Wireless mouse or cordless mouse, is a battery-powered device that transmits data using wireless technology.

14

Input The Keyboard Is an input device that contains keys users press to

enter data and instructions into a computer Desktop computer keyboard often attach to the

System Unit using Cable: a serial port or USB port. Without cables : IR or Bluetooth

Wireless keyboard or cordless keyboard, is a battery-powered device that transmits data using wireless technology

15

Computer Keyboard Keys

Function Keys Cursor-Movement Keys Numeric Keypad Toggle Keys (Caps Lock, Num Lock) Modifier Keys (Shift, Alt, Ctrl) Windows Keys Print Screen

Standard Computer Keyboard16

17

Input Scanners and Reading Devices Some input devices save time by capturing

data directly from a source document Optical scanner Optical readers Bar code readers RFID readers Magnetic strip card readers

18

Input Optical Readers

Is a device that uses a light source to read characters, marks and codes and then converts them into digital data that a computer can process.

Two technologies used by optical readers are

Optical character recognition.

Optical mark recognition.

19

Input 3- Bar Code Readers Also called bar code scanner

Is an electronic device that uses laser beams for reading printed barcodes.

Barcode is an identification code that consists of set of vertical lines and spaces of different widths

The barcode represent the data that identifies the manufacturer and the item

20

Input And Output 4- RFID Readers Radio-frequency identification Is a technology that uses radio signals to communicate with

a tag placed in or attached to an object, an animal, or a person.

RFID tags, which contain a memory chip and an antenna, are available in many shapes and size.

RFID reader reads information on the tag via radio waves. It can be handheld devices or mounted in a stationary object such as a doorway.

21

Input 5- Magnetic Strip Card Readers Often called a mag-strip reader, reads the Magnetic strip on

the back of credit cards or other similar cards. The strip contains information identifying you. Some information stored in the strip includes your name,

account number, the card expiration date, and a country code. If the Magnetic strip card readers rejects your card, it is

possible that the Magnetic strip is scratched, dirty or erased. Exposure to magnetic field can erase the contents of a card’s

magnetic stripe.

22

Input Biometric Input

Is the technology of authenticating a person’s identity by verifying a personal characteristic.

Biometric devices grant users access to programs, systems, or rooms by analyzing some physiological or behavioral characteristic.

Such as fingerprints, eye patterns, voice patterns, facial features, signatures and hand geometry.

23

Input Biometric Input

Fingerprint scanner Face recognition system Hand geometry system Voice verification system Signature verification

system Iris recognition system

What is Output ? Any information that has been processed

and comes from a computer or computer device is considered as output

When someone is viewing output, they're seeing it on an output device such as a computer monitor or a hard copy print out.

24

Output Device An output device is any piece

of computer hardware equipment used to communicate the results of data processing carried out by an information processing system (such as a computer) which converts the electronically generated information into human-readable form

25

26

Output Devices Processed data from a computer Text, graphics, photos, audio, video Common output devices

Monitor Printer Plotter Voice

27

Monitors Most frequently used output

device

Size is measured by diagonal of

screen

Common sizes: 15, 17, 19, 21

inches

Clarity is indicated by resolution

Measured in pixels

More pixels = better clarity

28

Monitor Standards

Resolution capabilities indicated by a monitor’s

standard

Video Graphics Array (VGA)

Super Video Graphics Array (SVGA)

Extended Graphics Array (XGA)

Super Extended Graphics Array (SXGA)

Ultra Extended Graphics Array (UXGA)

29

Monitor Types

Cathode-Ray Tubes (CRT) Most common

Flat-panel monitors (Liquid Crystal Display) Passive-matrix

images created by scanning the entire screen

Active-matrix (Thin Film Transistor TFT) each pixel is individually activated

eBook readers Data projectors High-definition television (HDTV)

30

Printers Produces hard copy output Ink-jet printer

Inexpensive and for home use

Sprays droplets of ink

Produce very sharp images Laser printer

More expensive, fast printing speed

Laser produced excellent letter and images

31

Laser Printing

32

Other Printers Dot-matrix

Series of pins on print head Inexpensive, not high quality

Chain/Line printer Used on networks by Org.

Plotter Maps, architectural drawings High quality, larger sized output

33

Output Devices Optical Disks: CD-ROM and DVD

CD-ROM (Compact Disk - Read Only Memory) By its definition, CD-ROM is Read Only. Special CD drives “burn” information into blank CDs.

Burn: A laser is used to “burn” craters into the surface to represent a binary 1.

Two main types of CDs: CD-R (Compact Disk - Recordable) CD-WR (Compact Disk – Re-Writable)

It takes longer to write to a CD-R than a hard drive. Special software is needed to record.

Storage Devices

34

Data Units

Name Equal to Size in Bytes Bit 1 bit 1/8 Byte 8 bits 1 Kilobyte 1,024 bytes 1,024 Megabyte 1,024 kilobytes 1,048,576 Gigabyte 1,024 megabytes 1,073,741,824 Terabyte 1,024 gigabytes 1,099,511,627,776

35

Storage UnitsName What can it store?

Byte A single letter, like "A."

Kilobyte A 14-line e-mail. A pretty lengthy paragraph of text.

Megabyte A good sized novel.

Gigabyte Roughly 300 MP3s or 40 minutes of video at DVD quality. A CD holds about three quarters of a gigabyte.

Terabyte 1,000 copies of the Encyclopaedia Britannica. Statistically, the average person has spoken about this much by age 25!

36

Storage: Holding Data for Future Use

Storage is dependent on two parts: Recording media to hold the data

Hard disks Flash memory CDs and DVDs

A storage device, which is hardware that contains the tools to place the data on the recording media

37

Storage: Holding Data for Future Use

A hard disk drive (hard disk) is: The most important storage device A high-capacity, high-speed device Considered secondary storage (fixed

storage), compared with memory/RAM, which is categorized as primary storage

38

Storage: Holding Data for Future Use

Hard disk drives Are random access storage devices and

permit direct retrieval of desired data Contain a coating of magnetic material used for data storage

39

Storage: Holding Data for Future Use

Hard disks record data on concentric bands called tracks.

Tracks are divided into sectors.A group of two or more sectors is a cluster.

40

Storage: Holding Data for Future Use

41

Storage: Holding Data for Future Use

The computer’s operating system stores in a table the file name and its location on the disk. The File Allocation Table (FAT) is the table

created by older versions of Microsoft Windows. The New Technology File System (NTFS) is

the present system used for tracking file locations.

42

Performance Measures of Disks

Access time – the time it takes from when a read or write request is issued to when data transfer begins. Consists of: Seek time – time it takes to reposition the arm over

that correct track. Rotational latency – time it takes for the sector to

be accessed to appear under the head.

Data-transfer rate – the rate at which data can be retrieved from or stored to the disk.

43

Storage: Holding Data for Future Use

Hard disk performance Disk cache is a type of cache memory.

CPU looks in the disk cache before going to the hard disk.

Using the disk cache speeds up data retrieval.

44

Tracks on a CD

A CD has one long track on it full of Pits and Lands.

This tracks begins at the centre of the disk and work outwards in a tight spiral.

45

Reading and Writing to a CD-ROM

Powerful laser ‘burns’ disk surface

Laser ‘burns’ pits into surface

Weak laser reads surface

Detector measures reflected light

46

How a CD-ROM is read

Data is encoded onto the CD using a series of ‘Pits' and ‘Lands‘.

A change from a Pit to a Land is read as a 1 and no change or a Land is read as a 0.

In this figure, it will read as: 01001010 Remember Your ASCII! Therefore 01001010 = 74 = Letter J 8 Bits = 1 Byte = 1 Character of TextLa

ser

Pit

Change Change Change

Land Land Pit Land

Light Sensor

Reflected Light

Top of CD ROM Disk

Bottom of CD ROM Disk

47

Any Questions !!!

END OF LECTURE 748