INTRODUCTION TO INFORMATION & COMMUNICATION TECHNOLOGY (ICT) LECTURE 3 : WEEK 3 CSC-110-T

Transcription

1 INTRODUCTION TO INFORMATION & COMMUNICATION TECHNOLOGY (ICT) LECTURE 3 : WEEK 3 CSC-110-T Credit : (2 + 1) / Week 2 TEXT AND REF. BOOKS 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 1

2 3 MOBILE ALERT Kindly Switch Off your Mobile/Cell Phone OR Switch it to Silent Mode Please 4 GOOGLE SITE ADDRESS FOR LECTURE NOTES AND STUDY MATERIAL DOWNLOAD, PLEASE VISIT : OR TYPE SHUCSC110 & GOOGLE 2

3 INPUT/OUTPUT/STORAGE DEVICES 5 Presented by: Flt. Lt. Shujaat H. Butt (R) MS. Telecomm. & Network Management, UK Masters (CS), Bahria University Khi, Pakistan Prince2 Project Management (Foundation) Certified Microsoft Certified Professional (MCP) Learning Objectives Understanding of the following, Devices Keyboard, Mouse, Touchscreen etc Output Devices Monitors, Printers etc Storage Devices Hard Disk Drive, Optical Storage etc 3

4 7 is any data and instructions entered into the memory of a computer Device is any hardware component that allows users to enter data and instructions into a computer 8 Device: Keyboard and pointing devices Pointing devices: Mouse is a pointing device because it allows a user to control a pointer on the screen. 4

5 9 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. 10 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. 5

6 11 Type of Mouse WIRELESS MOUSE OPTICAL MOUSE A TRACKBALL MOUSE GSTICK WIRELESS MOUSE 12 6

7 22-Feb Mouse Optical/Laser mouse is Mouse connects to a computer in several way: More precise than a mechanical mouse Dose not require cleaning as does a mechanical mouse. Also it is bit expensive than mechanical mouse. 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. 7

8 15 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 Computer Keyboard Keys 16 Function Keys Cursor-Movement Keys Numeric Keypad Toggle Keys (Caps Lock, Num Lock) Modifier Keys (Shift, Alt, Ctrl) Windows Keys Print Screen 8

9 17 18 Scanners and Reading Devices Some input devices save time directly from a source document Optical scanner Optical readers Bar code readers RFID readers by capturing data 9

10 19 Optical Scanner An optical scanner, usually called a scanner, is a light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can process 20 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. 10

11 21 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 And Output 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. 11

12 23 Biometric 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. 24 Biometric Fingerprint scanner Face recognition system Hand geometry system Voice verification system Signature verification system Iris recognition system 12

13 What is Output? 25 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. Output Device 26 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 13

14 Output Devices 27 Processed data from a computer Text, graphics, photos, audio, video Common output devices Monitor Printer Plotter Voice Monitors 28 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 14

15 Monitor Standards 29 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) HD (1920x1080) 2K (2048x1080) 4K (4096x2160) Printers 30 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 15

16 Laser Printing 31 Other Printers 32 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 16

17 Storage Devices 33 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,

18 Storage Units Name Byte Kilobyte Megabyte Gigabyte Terabyte What can it store? A single letter, like "A." A 14-line . A pretty lengthy paragraph of text. A good sized novel. Roughly 300 MP3s or 40 minutes of video at DVD quality. A CD holds about three quarters of a gigabyte. 1,000 copies of the Encyclopaedia Britannica. Statistically, the average person has spoken about this much by age 25! 35 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 36 18

19 Storage: Holding Data for Future Use A hard disk drive (hard disk) is: The most important storage device A high-capacity, device Considered secondary storage (fixed storage), compared with memory/ram, which is categorized as primary storage 37 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 38 19

20 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. 39 Storage: Holding Data for Future Use 40 20

21 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. 41 Performance Measures of Disks 42 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. 21

22 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. 43 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 44 22

23 Laser 22-Feb-18 How a CD-ROM is read Top of CD ROM Disk Change Change Change Pit Land Land Pit Land Bottom of CD ROM Disk Light Sensor Reflected Light 45 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: Remember Your ASCII! Therefore = 74 = Letter J 8 Bits = 1 Byte = 1 Character of Text Learning Outcome Devices Keyboard, Mouse, Touchscreen etc Output Devices Monitors, Printers etc Storage Devices Hard Disk Drive, Optical Storage etc 23

24 47 END OF LECTURE Any Questions!!! 24