CH003
- 1. Computer Hardware Chapter 3 Copyright © 2010 by the McGraw-Hill Companies, Inc. All rights reserved.McGraw-Hill/Irwin
- 2. 3-2 Learning Objectives Understand the history and evolution of computer hardware Identify the major types and uses of microcomputer, midrange, and mainframe computer systems Outline the major technologies and uses of computer peripherals for input, output, and storage
- 3. 3-3 Learning Objectives Identify and give examples of the components and functions of a computer system Identify the computer systems and peripherals you would acquire or recommend for a business of your choice, and explain the reasons for your selection
- 4. 3-4 Pre-Computer Calculations Counting on fingers and toes Stone or bead abacus – Calculate comes from calculus, the Latin word for small stone 1642: first mechanical adding machine – Invented by Blasé Pascal, wheels moved counters – Modified in 1674 by Von Leibnitz
- 6. 3-6 Pre-Computer Calculations Age of industrialization – Mechanical loom used punch cards Above left: Punch card reader. Above right: Punch card writer
- 7. 3-7 Early Computing 19th Century – Charles Babbage proposed the Analytical Engine, which could calculate, store values in memory, perform logical comparisons – Never built due to of lack of electronics 1880s – Hollerith’s punched cards used to record census data using On/Off patterns – representing digits and letters. – The holes turned sensors On or Off when run through tabulating machine – This company became the foundation for IBM
- 8. 3-8 Electronic Computers 1946 - First Generation Computer – ENIAC (Electronic Numerical Integrator and Computer ) – Programmable – 5000 calculations per second – Used vacuum tubes – Drawbacks were size and processing ability (140 square meters)
- 9. 3-9
- 10. 3-10 ENIAC
- 11. 3-11 Electronic Computers 1950s – ENIAC replaced by UNIVAC 1, then IBM 704 – Calculations jumped to 100,000 per second
- 12. 3-12 Waves of Computing Late 1950s - Second Generation – Transistors replaced vacuum tubes – 200,000 to 250,000 calculations per second
- 13. 3-13 Waves of Computing Mid-1960s - Third Generation – Integrated circuitry and miniaturization 1971 - Fourth Generation – Further miniaturization, multiprogramming, virtual storage 1980s - Fifth Generation – Millions of calculations per second
- 14. 3-14 Microcomputers 1975 – ALTAIR, programmed by flicking switches 1977 – Commodore & Radio Shack produce PCs
- 15. 3-15 Microcomputers 1979 – Apple computer, the fastest selling PC. 1982 – IBM introduced the PC, which changed the market
- 16. 3-16 Categories of Computer Systems
- 17. 3-17 Microcomputer Systems Computing power now exceeds that of the mainframes of previous generations Called a personal computer or PC Relatively inexpensive Hand-held, notebook, laptop, tablet, portable, desktop, and floor-standing Networked professional workstations used by businesses
- 19. 3-19 Microcomputer Systems Apollo 11 spacecraft Apollo 11 spacecraft Today's computers 2.048 MHz CPU 4 GHz 70 Pounds 1 Pound
- 21. 3-21 Microcomputer Uses Workstations Supports heavy mathematical computer and graphics display demands CAD, investment, and portfolio analysis Network Servers More powerful than workstations Coordinates telecommunications and resource sharing Supports small networks (LAN)and Internet or intranet websites
- 23. 3-23 Microcomputer Uses Terminals – Any device that allows access to a computer Types – Network (Windows or Internet) – Intelligent e.g. Transaction
- 24. 3-24 Terminals
- 25. 3-25 Network Computers Microcomputer designed for use with internet and intranets with limited computing applications. Operating system, applications and storage ready , from the network servers Low TCO Ease of software distribution and licensing Computing platform standardization
- 26. 3-26 Information Appliances Hand-held microcomputer devices also Known as personal digital assistants (PDAs) – Web-enabled PDAs use touch screens, handwriting recognition, or keypads so that mobile workers use to access email or the Web, exchange data(appointments, to do list) with desktop PCs or servers – Latest entrant is the BlackBerry, iPhone PDAs include – Video-games
- 28. 3-28 Midrange Systems High-end network servers that handle large-scale processing of business applications – Not as powerful as mainframes – Less expensive to buy, operate, maintain Often as a powerful network server used to manage – Large Internet websites, intranets, extranets – Integrated, enterprise-wide applications
- 29. 3-29 Mainframe Computer Systems Large, fast, powerful computer systems – Large primary storage capacity – Reduction in acquisition and operating cost (coolers) – High transaction processing – Handles complex computations – E.g. international banks, oil companies
- 30. 3-30 Mainframes
- 31. 3-31 Supercomputer Systems Extremely powerful systems designed for… – Scientific, engineering, and business applications that requires massive numeric computations Markets include… – Government research agencies – Large universities – Major corporations – E.g. global weather forecasting Uses parallel processing or (MPP) – Billions to trillions of operations per second (gigaflops and teraflops) – Price range
- 32. 3-32 The Next Wave of Computing Harnessing the infinite amount of unused computing power Desktops and laptops within an organization Distributed or grid computing (opposite to traditional supercomputers) Parallel computing that relies on complete computers connected to a network Harnesses the unused CPU power in all connected computers, even between organizations
- 34. 3-34 Computer System Concept System of hardware devices organized by function Input Processing Output Storage Control
- 36. 3-36 Moore’s Law Doubling of the number of transistors per integrated circuit every 18 to 24 months
- 37. 3-37 Computer Peripherals: Input, output, and storage technology
- 38. 3-38 Peripherals Separate from, and not under the control of, the CPU Offline Devices Separate from the CPU, but electronically connected to (and controlled by) it Online Devices Generic name for all input, output, and secondary storage devices Peripheral Parts of the computer system (not the CPU) All online devices
- 40. 3-40 Input Technologies Common input devices – Keyboard – Graphical User Interface (GUI) – Electronic mouse and trackball – Pointing stick – Touchpad – Touch screen
- 41. 3-413-41 Input technologies Keyboard: most widely-used Graphical user interface (GUI) – Icons, menus, windows, buttons, bars – Used for selection
- 42. 3-423-42 Pointing Devices Electronic Mouse Trackball – Stationary device like a mouse – Roller ball used to move cursor on screen. Pointing Stick – Small eraser head-like device in keypad – Moves cursor in direction of pressure placed on stick.
- 43. 3-433-43 Pointing Devices Touchpad – Small rectangular touch-sensitive surface – Moves the cursor in the direction of finger moves on the pad Touch Screen – use computer by touching screen – Video display screen that emits a grid of infrared beams, sound waves, or a slight electric current – Grid is broken when the screen is touched.
- 44. 3-44 Pen-Based Computing Used in Tablet PCs and PDAs – Pressure-sensitive layer, similar to touch screen, under liquid crystal display screen – Software digitizes handwriting, hand printing, and hand drawing
- 45. 3-45 Speech Recognition Systems Speech may be the future of data entry – Easiest, most natural means of human communication Recognizing speech patterns – Discrete, requires pauses between each word – Continuous speech recognition software (CSR) recognizes continuous, conversationally paced speech
- 46. 3-46 Speech Recognition Software Speech recognition systems digitize, analyze, and classify speech and sound patterns – Compares to a database of sound patterns – Passes recognized words to software – Typically requires voice recognition training Speaker-independent systems – Allow computers to recognize words from a voice never heard before – Typically used in voice-messaging computers
- 47. 3-47 Optical Scanning Devices read text or graphics and convert them into digital computer input – Enables direct entry of data from source documents Document management library system – Scans documents, then organizes and stores them for easy reference or retrieval
- 48. 3-48 Optical Scanning Optical Character Recognition (OCR) Software that reads characters and codes Used to read merchandise tags, sort mail, score tests, read bar codes
- 49. 3-49 Other Input Technologies Magnetic Stripe Magnetic Ink Character Recognition (MICR) Digital Cameras Smart Cards
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- 51. 3-51 Output Technologies Voice Response Increasingly found along with video displays in business applications Video Displays Cathode-ray tube (CRT) Printed Output Inkjet and laser Liquid crystal display (LCD) Plasma displays (TVs, flat-panel monitors)
- 53. 3-53 Computer Storage Fundamentals On (1) or Off (0) Data processed & stored in computer systems through On/Off signals Uses two-state (binary) data representation Uses two-state (binary) data representation Smallest element of data Either zero or one BitBit Group of eight bits, which operate as a single unit Represents one character or number ByteByte
- 54. 3-54 Representing Characters in Bytes
- 55. 3-55 Storage Capacity Measurement Kilobyte (KB) One thousand bytes Megabyte (MB) One million bytes Gigabyte (GB) One billion bytes Terabyte (TB) One trillion bytes Petabyte (PB) One quadrillion bytes
- 56. 3-56 Direct (Random) and Sequential Access
- 57. 3-57 Direct Access Direct or Random Access – Also called random access. – Directly store and retrieve data – Each storage position has: a unique address can be accessed in the same length of time – Represent primary storage devices such as: Semiconductor memory chips, magnetic disks.
- 58. 3-58 Sequential Access Sequential Access – Data is stored and retrieved sequentially – Must be accessed in sequence by searching through prior data – Media such as: Magnetic tape known as sequential access devices.
- 59. 3-59 Semiconductor Memory Microelectronic semiconductor memory chips are used for primary storage – Advantages: small size, fast, shock and temperature resistance – Disadvantages: volatility; must have uninterrupted electric power or loses memory
- 60. 3-60 Types of Semiconductor Memory Random Access Memory (RAM) Read-Only Memory (ROM) 1. Most widely used primary storage medium 2. Volatile memory 3. Read/write memory 1. Permanent storage “nonvolatile” 2. Can be read, but not overwritten 3. Frequently used programs burnt into chips during manufacturing 4. Called firmware
- 61. 3-61 Flash Drives Sometimes called a jump drive – Uses a small chip containing thousands of transistors – Can store data for virtually unlimited periods without power – Easily transported – Highly durable – Storage capacity of up to 20 GB – Plugs into any USB port
- 62. 3-62 Magnetic Disks Used for secondary storage – Fast access and high capacity – Reasonable cost Hard Disk Drives & Floppy Disks (diskettes)
- 63. 3-63 RAID Storage Redundant Arrays of Independent Disks – Provides virtually unlimited online storage – 6 to more than 100 hard disk drives are combined into a single unit – Data is accessed in parallel, over multiple paths, from many disks – Redundant storage of data on several disks provides fault-tolerant capacity Storage area networks can interconnect many RAID units
- 64. 3-64 Magnetic Tape Secondary storage – Tape reels, cassettes, and cartridges – Used in robotic, automated drive assemblies – Archival and backup storage – Lower-cost storage solution
- 66. 3-66 Uses of Optical Disks Image Processing Long-term storage of historical image files Storage of scanned documents Publishing Medium Allows fast access to reference materials Catalogs, directories, and so on Interactive Multimedia Applications Video games, educational videos, and so on
- 67. 3-67 Radio Frequency Identification (RFID) One of the newest, fastest growing storage technologies – System for tagging and identifying mobile objects – Used with store merchandise, postal packages, casino chips, pets – Special reader allows objects to be tracked as they move from place to place – Chips half the size of a grain of sand Passive chips derive power from reader signal Active chips are self-powered
- 68. 3-68 RFID Versus Bar Coding Invisible nature of the system Capacity to transmit fairly sophisticated messages Privacy Concerns Privacy Concerns Scans from greater distance Can store dataRFIDRFID
Editor's Notes
- #23: Genetic image analysis workstation Example CAD
- #24: Dumb terminals: limited \ no processing capabilities. Example: Keyboard\ monitor. Intelligent terminals: A computer input/output device with its own memory and logic circuits which can perform certain operations normally carried out by the computer. Also known as smart terminal. Transaction terminals: ex debit card” magnetic strep reader” barcode reader ATM
- #37: Originally observed in 1965, Moore’s Law holds true today Common corollary of Moore’s Law… Computing prices will be cut in half every 18 to 24 months This has been consistently accurate Applies to cost of storage as well
- #42: Trend to natural user interface as opposed to paper source documents
- #50: Magnetic Stripe Reads the magnetic stripe on credit cards Smart Cards Microprocessor chip and memory on credit card Used more in Europe than in the U.S. Digital Cameras Allows you to shoot, store, and download photos or full-motion video with audio into a PC Images and audio can then be edited or enhanced Magnetic Ink Character Recognition (MICR) Identification numbers of bank and account printed in magnetic ink on bottom of check Used by banks to magnetically read checks and deposit slips Requires an iron oxide-based ink Reader-sorter equipment magnetizes the ink, then passes it under a reading head to sense the signal
- #53: Storage media cost, speed, and capacity tradeoffs. Cost increases with faster access speeds but decreases with increased capacity.
- #54: Binary representation Data are processed and stored in computer system through the presence or absence of signals Either ON or OFF ON = number 1 OFF = number 0 Bit (short for binary digit) Smallest element of data Either zero or one the capacity of memory chips is represented in bits Byte Group of eight bits which operate as a single unit Represents one character or number
- #63: Floppy Disks (diskettes) Magnetic disk inside a plastic jacket Hard Disk Drives (hard drives) Magnetic disk, access arms, and read/write heads in sealed module for stable environment The design allow for higher speed, greater data recording, more tolerance. Fixed or removable Capacity from several hundred MBs to hundreds of GBs