1. I Information Systems Technology Ross Malaga 2 "Part I Understanding Information Systems Technology" Copyright © 2005 Prentice Hall, Inc. 2-1 COMPUTER HARDWARE TECHNOLOGIES

2. Copyright © 2005 Prentice Hall, Inc. 2-2 LEARNING GOALS Identify the major components of modern PCs. Explain how the components of a computer work together; –Explain the role of the CPU and how it operates. –Explain input devices and how they operate. –Describe output devices and how they operate. –Describe multimedia and alternative I/O devices. –Explain the role of primary storage. –Describe secondary storage devices and how they operate. Describe various types of computers.

3. Copyright © 2005 Prentice Hall, Inc. 2-3 Bead Bar Wants Computers Hardware choices should be driven by the specific software the company needs to run Some of the requirements –Meredith – Computers for managers –Suzanne – Computer in each studio –Mitch – Notebook (laptop) needed for cruise ships –Julia – Keep the total hardware cost under $20,000 –Miriam – Marketing can save money by using computers to develop their own materials –Rachel – Mobile computing needed for traveling purchasing rep –Jim – Must be ergonomically designed

4. Copyright © 2005 Prentice Hall, Inc. 2-4 The Core Computer Components Input device(s) Output device(s) Primary storage Secondary storage Central processing unit (CPU) Busses

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6. Copyright © 2005 Prentice Hall, Inc. 2-6 The Historical Development of Computers Babbage’s Analytical Engine – 1820s – 1870s –Punched card program –Lady Ada Byron, the first programmer Herman Hollerith –Hollerith code –Punched card tabulating machines – 1890 census ENIAC during WWII used vacuum tubes 1960s introduced transistor to replace tubes 1970s – introduction of the microprocessor

7. Copyright © 2005 Prentice Hall, Inc. 2-7 The Rise of the PC 1974 – Altair 8800 – the first PC 1976 – Wosniak and Jobs – Apple I 1977 – Apple II –Plastic case –Keyboard –Capable of color graphics 1981 – IBM PC (introduction of MS-DOS) 1984 – Apple Macintosh –Graphical User interface (GUI) pioneered a Xerox PARC

8. Copyright © 2005 Prentice Hall, Inc. 2-8 Input Devices Human input devices –Allow person to send data to the computer –Keyboard –Mouse (and other pointing devices) Machine-readable input devices –Send data directly to computer without human involvement –No human involvement means no human error –Usually faster than human input

9. Copyright © 2005 Prentice Hall, Inc. 2-9 Keyboard as Input Device Easy way to enter text, numbers, and simple commands Follows the layout of the typewriter QWERTY keyboard leads to RSIs –Repetitive Stress Injuries –Requires increased attention to ergonomics of the work environment Posture Lighting Working

10. Copyright © 2005 Prentice Hall, Inc. 2-10 Machine-readable Input Devices Bar code scanners –Uses light to read series of coded stripes –Universal Product Code (UPC) – Adams.comAdams.com –Package tracking at UPSUPS Optical Character Recognition (OCR) –Software that works with scanner –Translates scanned digital image to character that user can recognize and manipulate Magnetic Ink Character Recognition (MICR) –Character recognition technology used by banks to allow rapid routing of checks between banks

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12. Copyright © 2005 Prentice Hall, Inc. 2-12 Output Devices Monitors –Cathode ray tube (CRTs) –Liquid crystal displays (LCDs) –Quality of display Resolution Dot pitch Touch screens –Input and output via display device

13. Copyright © 2005 Prentice Hall, Inc. 2-13 Printers Speed and resolution –Pages per minute –Dots per inch Number of ink dots to fill a square inch Higher DPI the greater the page clarity Impact –Create image by striking paper and ribbon –Dot-matrix Non-impact –Create image by spraying or rolling ink on the page

14. Copyright © 2005 Prentice Hall, Inc. 2-14 Non-impact Printers Ink-jet technology printers –Spray ink on the paper –Small –Quiet –Color is readily and cheaply available Laser printers –Laser heats drum which rolls ink (toner) on paper –Can be faster than ink-jet –Color more expensive than ink-jet

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16. Copyright © 2005 Prentice Hall, Inc. 2-16 Multimedia I/O Devices Music, images, and video –Convert content to digital form –How MP3s work at HowStuffWorks.comHow MP3s work –Digital cameras ; digital camera phones –Digital Video DVD recorders – Sony HandicamSony Handicam Game controllers Virtual reality (VR) Voice recognition Text-to-speech Brain wave input

17. Copyright © 2005 Prentice Hall, Inc. 2-17 Primary Storage Digital data stored in bits – BInary digiTs Combination of 8 bits is called a byte Different combinations of bits represent different symbols –ACSII –EBCDIC All data and programs are represented in bits –Video –Pictures –Text

18. Copyright © 2005 Prentice Hall, Inc. 2-18 Primary Storage (Continued) The main memory of the computer Stored on semiconductor chips –RAM – random access memory Volatile Cache memory –Internal – ultra high speed and VERY expensive –External – very high speed and less expensive than internal cache –ROM – read only memory Non-volatile Primary storage holds all programs that are running and the data those programs use

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20. Copyright © 2005 Prentice Hall, Inc. 2-20 Secondary Storage Nonvolatile storage of digital data Magnetic or optical Magnetic media –Sequential access (tape) or direct access (HDD) –Hard disk drives Metal disk with metallic coating Disk spins at speeds of up to 7000 rpm RAID – redundant array of inexpensive disks –Floppy disks –Magnetic tape –Zip disks and other magnetic storage alternatives

21. Copyright © 2005 Prentice Hall, Inc. 2-21 Hard Disk Drives and Direct Access

22. Copyright © 2005 Prentice Hall, Inc. 2-22 Optical Secondary Storage Compact disks (CDs) –600 MB capacity –CD-ROM –CD-R –CD-RW Digital versatile disks (DVDs) –2 – 17 GD capacity –DVD –DVD+/-R –DVD+/-RW

23. Copyright © 2005 Prentice Hall, Inc. 2-23 The Central Processing Unit Two main components –Arithmetic and logic unit (ALU) –Control unit (CU) –Registers are used as scrap paper – intermediate results Speed measured in hertz –Megahertz – millions of instructions per second –Gigahertz – billions of instructions per second

24. Copyright © 2005 Prentice Hall, Inc. 2-24 Moore’s Law on Processor Speed

25. Copyright © 2005 Prentice Hall, Inc. 2-25 Computer Program Instruction Execution Connect all the pieces together –Bus – electrical pathway –All digital data moves from component to component on the bus Executing an instruction –Control unit fetches next instruction from primary storage and stores it onboard the CPU –The control unit decodes the instruction –The ALU executes the instruction possibly accessing other data in primary storage Cycle is repeated millions of times per second

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27. Copyright © 2005 Prentice Hall, Inc. 2-27 Types of Computers Supercomputers Mainframes Minicomputers Workstations Desktop computers Notebook computers (laptops) Handheld computers (PDAs)

28. Copyright © 2005 Prentice Hall, Inc. 2-28 Bead Bar Consultant How Computer Hardware Issues Affect the Bead Bar –Meredith – Needs to understand the technology and terms –Suzanne – Computers in studios to improve studio operations –Leda – Use computers to improve franchise record keeping and marketing –Mitch –Portable computer to allow working while traveling –Julia – Concerned about costs, including ROI –Miriam – Use multimedia to develop marketing materials –Rachel – Use bar codes and handhelds to reduce errors and streamline operations –Jim – Upgrading skills of employees and finding new employees to hire with the proper computer skills

29. Copyright © 2005 Prentice Hall, Inc. 2-29 Learning Goals Summary In this chapter you have learned: The major components of modern PCs How the components of a computer work together The role of the CPU and its operation Input devices and how they operate Output devices and how they operate Multimedia and alternative I/O devices The role of primary storage Secondary storage devices and operation The various types of computers