Computer Hardware Chapter 3 McGraw-Hill/Irwin Copyright © 2010 by the McGraw-Hill Companies, Inc. All rights reserved.

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

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

Case 1: IBM, Wachovia, and Paypal Researchers at the Cancer Institute use grid computing technology to convert images of cancerous tissues and cells into digital images The grid checks digitized images for accuracy to ensure the bits/bytes translate into diagnoses IBM, researchers, and doctors are building an image database to help oncologists diagnose and treat cancer patients faster and better Grid computing technologies avoid the need for expensive, dedicated hardware The processing load is distributed among commodity-priced equipment

Case Study Questions Applications for grid computing in this case include medical diagnosis and financial transaction processing What other areas would be well suited to the use of grid computing, and why? Provide examples from organizations other than those included in the case

Case Study Questions The joint effort by IBM and the Cancer Center of New Jersey works by digitalizing medical diagnoses on the World Community Grid What are the advantages & disadvantages of relying on a volunteer-based network?

Case Study Questions IBM, Wachovia, and Paypal are arguably large organizations. However, several vendors have started offering computing power for rent to smaller companies, using the principles underlying grid computing How could small and medium companies benefit from these technologies?

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 Blaise Pascal, wheels moved counters Modified in 1674 by Von Leibnitz Age of industrialization Mechanical loom used punch cards

Early Computing 19th Century 1880s 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 The holes turned sensors On or Off when run through tabulating machine This company became the foundation for IBM

Electronic Computers 1946 - First Generation Computer 1950s ENIAC Programmable 5000 calculations per second Used vacuum tubes Drawbacks were size and processing ability 1950s ENIAC replaced by UNIVAC 1, then IBM 704 Calculations jumped to 100,000 per second

Waves of Computing Late 1950s - Second Generation Transistors replaced vacuum tubes 200,000 to 250,000 calculations per second Mid-1960s - Third Generation Integrated circuitry and miniaturization 1971 - Fourth Generation Further miniaturization, multiprogramming, virtual storage 1980s - Fifth Generation Millions of calculations per second

Microcomputers 1975 ALTAIR, programmed by flicking switches 1977 Commodore & Radio Shack produce PCs 1979 Apple computer, the fastest selling PC thus far 1982 IBM introduced the PC, which changed the market

Categories of Computer Systems

Microcomputer Systems Called a personal computer or PC Computing power now exceeds that of the mainframes of previous generations Relatively inexpensive Networked professional workstations used by businesses Hand-held, notebook, laptop, tablet, portable, desktop, and floor-standing

Recommended PC Features

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 and Internet or intranet websites

Microcomputer Uses Terminals Types Any device that allows access to a computer Types Dumb Intelligent (Windows or Internet) Transaction

Corporate PC Criteria Solid performance at a reasonable price Operating system ready Connectivity Security-equipped

Information Appliances Hand-held microcomputer devices Known as personal digital assistants (PDAs) Web-enabled PDAs use touch screens, handwriting recognition, or keypads Mobile workers use to access email or the Web, exchange data with desktop PCs or servers Latest entrant is the BlackBerry PDAs include Video-game consoles Cellular and PCS phones Telephone-based home email appliances

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 used to manage Large Internet websites, intranets, extranets Integrated, enterprise-wide applications First became popular as minicomputers Used as front-end servers Assists mainframes with telecommunications and networks

Mainframe Computer Systems Large, fast, powerful computer systems Large primary storage capacity High transaction processing Handles complex computations Widely used as superservers for… Large client/server networks High-volume Internet websites Becoming a popular computing platform for… Data mining, warehousing, electronic commerce applications

Supercomputer Systems Extremely powerful systems designed for… Scientific, engineering, and business applications Massive numeric computations Markets include… Government research agencies Large universities Major corporations Uses parallel processing Billions to trillions of operations per second (gigaflops and teraflops)

The Next Wave of Computing Harnessing the infinite amount of unused computing power Desktops and laptops within an organization Distributed or grid computing Parallel computing that relies on complete computers connected to a network Harnesses the unused CPU power in all connected computers, even between organizations

Computer System Concept Input Control System of hardware devices organized by function Processing Storage Output

Computer System Concept

Computer Processing Speeds Early computers Milliseconds (thousandths of a second) Microseconds (millionths of a second) Current computers Nanoseconds (billionth of a second) Picoseconds (trillionth of a second) Program instruction processing speeds Megahertz (millions of cycles per second) Gigahertz (billions of cycles per second) Commonly called “clock speed”

Computer Processing Speeds Throughput Ability to perform useful computation or data processing assignments during a given period Speed is dependant on… Size of circuitry paths (buses) that interconnect microprocessor components Capacity of instruction processing registers Use of high-speed cache memory Use of specialized microprocessors, such as math coprocessor

Moore’s Law 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 Doubling of the number of transistors per integrated circuit every 18 to 24 months

Case 2: Apple, Microsoft, IBM, and Others WIMP Windows, icons, menus, and pointing devices have dominated computing for 15 years New human interface technologies will revolutionize the way we interact with computers Microsoft is working with Starwood Hotels & Resorts to introduce surface computing Hotel guests use a virtual concierge to manipulate maps, photos, restaurant menus… A logical extension of touch technology is gesture recognition Hand or finger movements across a screen, or close to it, without requiring an actual touch

Case Study Questions What benefits may Starwood Hotels derive from the introduction of touch-screen technology, as noted in the case? What possible disruptions may occur as a result?

Case Study Questions Bill Buxton of Microsoft stated that “Touch now may be where the mouse was in about 1983” What do you make of his comments, and what do you think it would take for touch technology to displace the WIMP interface? Advanced touch-screen technology is really a solution in search of a problem Do you agree with this statement?

Peripherals Peripheral Generic name for all input, output, and secondary storage devices Parts of the computer system (not the CPU) All online devices Online Devices Separate from the CPU, but electronically connected to (and controlled by) it Offline Devices Separate from, and not under the control of, the CPU

Peripherals Advice

Input Technologies Common input devices Keyboard Graphical User Interface (GUI) Electronic mouse and trackball Pointing stick Touchpad Touchscreen

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

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

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

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

Optical Scanning Scanners Optical Character Recognition (OCR) Compact desktop models are popular for low cost and ease of use Larger, more expensive flatbed scanners are faster, offer high-resolution color scanning Optical Character Recognition (OCR) Software that reads characters and codes Used to read merchandise tags, sort mail, score tests, read bar codes

Other Input Technologies Magnetic Stripe Smart Cards Digital Cameras 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) 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 Magnetic Ink Character Recognition (MICR)

Output Technologies Voice Response Video Displays Printed Output Increasingly found along with video displays in business applications Video Displays Cathode-ray tube (CRT) Liquid crystal display (LCD) Plasma displays (TVs, flat-panel monitors) Printed Output Inkjet and laser

Storage Tradeoffs

Computer Storage Fundamentals Uses two-state (binary) data representation On (1) or Off (2) Data processed & stored in computer systems through On/Off signals Bit Smallest element of data Either zero or one Group of eight bits, which operate as a single unit Byte Represents one character or number

Representing Characters in Bytes

Using Binary Code to Calculate

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

Direct (Random) and Sequential Access Direct or Random Access Directly store and retrieve data Each storage position has a unique address and can be accessed in the same length of time Semiconductor memory chips, magnetic disks Sequential Access Data is stored and retrieved sequentially Must be accessed in sequence by searching through prior data Magnetic tape

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

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 2. Can be read, but not overwritten 3. Frequently used programs burnt into chips during manufacturing 4. Called firmware

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

Hard Disk Drives & Floppy Disks (diskettes) Magnetic Disks Hard Disk Drives & Floppy Disks (diskettes) 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 Fixed or removable Capacity from several hundred MBs to hundreds of GBs Used for secondary storage Fast access and high capacity Reasonable cost

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

Magnetic Tape Secondary storage Tape reels, cassettes, and cartridges Used in robotic, automated drive assemblies Archival and backup storage Lower-cost storage solution

Optical Disks

Uses of Optical Disks Long-term storage of historical image files 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

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

RFID Versus Bar Coding Scans from greater distance RFID Can store data More information can be tracked Privacy Concerns Invisible nature of the system Capacity to transmit fairly sophisticated messages

Case 3: Kimberly-Clark & Daisy Brand Almost $20 billion in sales in 37 countries Wants to evolve into a demand-driven supply network Uses SAP for forecast-to-stock and order-to-cash processes Has been redesigning business processes and finding a way for technology to support those processes RFID helps trace trailers and raw materials

Case 3: Kimberly-Clark & Daisy Brand Daisy Brands Sells perishable products through Wal-Mart RFID helps manage flow of product and ensures marketing promotions proceed as planned Lets customers track their orders Knows when pallets of product arrive, and when they’re unpacked Can dispatch people to investigate anomalies

Case Study Questions Kimberly-Clark and Daisy Brands were two of the earliest adopters of RFID through their relationship with Wal-Mart How has that initiative fared since it was announced? Go online and research the most recent developments Prepare a report to highlight any successes and failures in the advancement toward a fully RFID-enabled supply chain for the giant retailer

Case Study Questions What is the value of having access to real-time (or near real time) information about sales and inventory? Are there any dangers to having this capability, such as overreacting to short-term trends?