Cartoonist Cartoonist Computer Hardware Engineer Computer Hardware Engineer Author Author.
Computer Hardware
description
Transcript of Computer Hardware
Computer Hardware
3-2
• 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
3-3
• 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.
Learning Objectives
3-4
Information System Resources
3-5
3-6
Early Computing
• 1880s– Punched cards turned sensors On or Off
• 1946 – ENIAC – First Digital computer - programmable– Used vacuum tubes – Would fill room 39 ft by 39 ft
• Late 1950s– Transistors replaced vacuum tubes– Smaller, faster, cooler
3-7
Waves of Computing
• First Generation - Prior to 1950– Vacuum tubes
• Second Generation - Late 1950s – Transistors & integrated circuits – Jack Kilby– 200,000 to 250,000 calculations per second
• Third Generation - Mid-1960s – Integrated circuitry and miniaturization
• Fourth Generation - 1971 – Further miniaturization– Multiprogramming and virtual storage
• Fifth Generation - 1980s – Millions of calculations per second
3-8
Age of Microcomputers
• 1975 – MITS introduced ALTAIR 8800.
• 1977– Commodore and Radio Shack
• 1979– Apple computer, fastest selling – Steve Jobs & Steve Wozniak
• 1982– IBM introduced the PC– Changed the market
3-9
Categories of Computer Systems
3-10
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 popular computing platform for…– Electronic commerce applications– Data mining and warehousing
3-11
Midrange Systems• High-end network servers
– Large-scale processing of business applications
• Not as powerful as mainframes– Less expensive to buy, operate, and maintain
• Often used to manage– Large Internet websites– Corporate intranets and extranets– Integrated, enterprise-wide applications
• Used as front-end servers– Assist mainframes with telecommunications and
networks
3-12
Supercomputer Systems
• Extremely powerful systems– 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) – Costs $5 to $50 million
3-13
Recommended PC Features
3-14
Corporate PC Criteria
• Solid performance, reasonable price• Operating system ready• Connectivity
– Network interface cards – Wireless capabilities
3-15
Information Appliances
• Hand-held microcomputer devices• Known as personal digital assistants (PDAs)
– Web-enabled – Touch screens, handwriting recognition, keypads– 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
• iPhone 4 and smart phones
3-16
Computer System Concept
3-17
Computer Processing Speeds• Commonly called “clock speed”• 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)
3-18
Moore’s Law
3-19
Peripherals Advice
3-20
Input Technologies
• Keyboard
• Graphical User Interface (GUI)
• Electronic Mouse
• Trackball
• Pointing stick
• Touchpad
• Touch screen
3-21
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
3-22
Speech Recognition Software
• Digitize, analyze, and classify speech and sound patterns– Compares to sound patterns in its vocabulary– Passes recognized words to the application
software
• Speaker-independent voice recognition systems– Recognizes words from never heard voice– Voice-messaging computers
3-23
Optical Scanning
• Converts text or graphics to digital
• Document management library system• Scanners
• Optical Character Recognition (OCR)– Reads characters and codes– Optical scanning wands
3-24
Optical Scanning
• QR code?
3-25
Optical Scanning
3-26
Other Input Technologies
• Magnetic Stripe on credit cards
• Smart Cards
• Digital Cameras
• Magnetic Ink Character Recognition (MICR)
3-27
Output Technologies
• Video Displays– Cathode-ray tube (CRT)– Liquid crystal displays (LCDs)– Plasma displays
• Printed Output– Dot matrix– Character printers– Inkjet printers spray ink– Laser printers
• Electrostatic process • Similar to a photocopying machine
3-28
Storage Tradeoffs
3-29
Representing Characters in Bytes
3-30
Using Binary Code to Calculate
3-31
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
3-32
Direct and Sequential Access
3-33
Types of Semiconductor Memory
• Random Access Memory (RAM)– Most widely used primary storage medium
– Volatile memory
– Read/write memory
• Read-Only Memory (ROM)– Permanent storage
– Can be read, but not overwritten
– Frequently used programs burnt into chips
during manufacturing process
– Called firmware
• Flash Drive
3-34
Flash Drives
• Jump drive, travel drive, etc.– Small chips thousands of transistors
– Stores data virtually unlimited periods without power
– Easily transported and highly durable
– Storage capacity of up to 20 GB
• New 1 TB
– Plugs into any USB port
3-35
Direct Access – Magnetic Disk
• Used for secondary storage– Fast access and high capacity– Reasonable cost
3-36
RAID Storage
• Redundant Arrays of Independent Disks– Arrays of hard disk drives
– Virtually unlimited online storage
– 6 to more than 100 small hard disk drives in a single unit
– Data are 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
3-37
Magnetic Tape
• Secondary storage– Tape reels, cassettes, and cartridges
– Used in robotic, automated drive assemblies
– Archival and backup storage
– Lower-cost storage solution
3-38
Optical Disks
3-39
Radio Frequency Identification (RFID)
• One of the newest and fastest growing storage technologies– System for tagging and identifying moving objects
• Merchandise, postal packages, casino chips, pets
– Tag 1 inch square– Chips half the size of a grain of sand
• Passive chips derive power from reader signal
• Active chips are self-powered
• Privacy Issues
3-40
Predictions for the Future
• Biological memories• Health remedies• Longer life spans• Virtual activities• Memory recall
3-41
RWC 3: Grid (cloud) Computing
• Grid (cloud) computing– Tapping into available computer power on other
systems– Better use of underutilized hardware– Avoid dedicated hardware costs
• Cancer Institute in New Jersey – Convert hundreds of thousands of images of
cancerous tissues and cells into digital images.– Check accuracy– Diagnose and treat cancer patients faster and with
more success.
3-42
RWC 4: Touch Screen Comes of Age
• The WIMP - Windows, Icons, Menus, and Pointing devices dominated for 15 years.
• New human interface technologies revolutionize interaction with computers.
• Microsoft and Starwood Hotels & Resorts introduce surface computing
• Gesture recognition is logical extension of touch technology
3-43
RWC 4: Touch Screen Comes of Age
3-44