Hardware for Educators Chapter 4 Hardware for Educators

CHAPTER 4 OBJECTIVES Describe the system unit Define the term bit, and describe how a series of bits are used to represent data Identify the major components of the system unit and explain their functions Explain how the CPU uses the four steps of a machine cycle to process data List the characteristics of a keyboard and identify various types of keyboards

CHAPTER 4 OBJECTIVES Identify various types of pointing devices Differentiate among the four types of output Identify the different types of output devices Explain the differences among various types of printers

CHAPTER 4 OBJECTIVES Differentiate between storage and memory Identify types of storage media and devices Explain how data is stored on floppy disks, hard disks, and CD-ROMs Differentiate between CD-ROMs and DVD-ROMs

THE SYSTEM UNIT System unit Box-like case that houses the electronic components of the computer that are used to process data

DATA REPRESENTATION Analog vs. Digital Digital Two states (1) on (0) off

DATA REPRESENTATION Binary number system Combination of ones and zeroes represent characters

DATA REPRESENTATION ASCII American Standard Code for Information Interchange Converting a keyboard stroke into a byte

THE COMPONENTS OF THE SYSTEM UNIT The Motherboard Contains many of the electronic components Chip A small piece of semiconducting material on which one or more integrated circuits are etched

THE COMPONENTS OF THE SYSTEM UNIT CPU and Microprocessor Interprets and carries out the basic instructions that operate a computer Microprocessor contains the CPU in a PC

CPU AND MICROPROCESSOR The Control Unit A component of the CPU that directs and coordinates most of the operations in the computer Fetch – get the next instruction from memory Decode – translate the instruction Execute – carry out the command Store the result – write the result to memory Machine cycle

CPU AND MICROPROCESSOR The Arithmetic/Logic Unit Performs the execution part of the machine cycle Arithmetic (addition, subtraction, multiplication, division) Comparison (greater than, equal to, less than) Logical (AND, OR, NOT)

CPU AND MICROPROCESSOR The System Clock Synchronizes all computer operations Each tick is called a clock cycle Faster clock means more instructions the CPU can execute each second Speed measured in megahertz (MHz) One million ticks of the system clock

CPU AND MICROPROCESSOR Memory Used to store data, instructions, and information The operating system and other system software Application programs Data being processed by application programs Bytes are stored at specific locations or addresses

Seats in a stadium are similar to addresses in memory: A seat in memory holds one person at a time, and an address in memory holds a single byte Both a seat and an address can be empty A seat has a unique identifying number and so does an address

CPU AND MICROPROCESSOR Memory Size of memory is measured by the number of bytes available

CPU AND MICROPROCESSOR Memory Volatile memory – contents are lost when the computer is powered down Nonvolatile memory – contents are not lost when the computer is powered down

CPU AND MICROPROCESSOR Random Access Memory (RAM) The memory chips in the system unit When the computer starts, operating system files are loaded from a hard disk into RAM Synchronous Dynamic RAM (SDRAM) Dual Inline Memory Module (DIMM)

CPU AND MICROPROCESSOR Random Access Memory (RAM) RAM Chips Smaller in size than processor chips Packaged on circuit boards called single inline memory modules (SIMMs) or dual inline memory modules (DIMMs)

CPU AND MICROPROCESSOR Random Access Memory (RAM) Configuring RAM The more RAM, the more programs and files a computer can work on at once Software usually tells you how much RAM is required Necessary RAM depends on what type of work the computer is used for

CPU AND MICROPROCESSOR Read-Only Memory (ROM) Cannot be modified Contents not lost when the computer is turned off

CPU AND MICROPROCESSOR Expansion Slots and Expansion Cards Expansion slot An opening, or socket, where a circuit board can be inserted into the motherboard Add new devices or capabilities to the computer Expansion card Circuit boards, such as a modem or graphics card, that add new capabilities to the computer

CPU AND MICROPROCESSOR Expansion Slots and Expansion Cards Three common types Video card Sound card Internal modem PC Cards Plug and Play

CPU AND MICROPROCESSOR Ports and Connectors Port Point of attachment to the system unit Usually on the back of the computer Connectors Used to plug into ports Male connectors Female connectors

CPU AND MICROPROCESSOR Ports and Connectors New ports USB USB 2.0 1394 (FireWire)

WHAT IS INPUT? Any data or instructions you enter into the memory of a computer Data – unorganized facts Program – series of instructions that tells the computer how to perform a task Command – an instruction given to a computer program User response – responses to questions or messages from the software

WHAT ARE INPUT DEVICES? Any hardware component that allows you to enter data, programs, commands, and user responses into a computer

WHAT ARE INPUT DEVICES? The Keyboard Primary input device Typing area Numeric keypad Toggle keys Status lights Arrow keys – arrow control keys Function keys Specialized buttons Wireless keyboards

WHAT ARE INPUT DEVICES? Pointing Devices An input device that allows you to control a pointer on the screen Block arrow I-beam Pointing hand

WHAT ARE INPUT DEVICES? Pointing Devices Mouse One or two button mouse Moving the mouse pointer Clicking Dragging Double-clicking Optical mouse Cordless mouse

WHAT ARE INPUT DEVICES? Touchpad and Pointing Stick Touchpad – small, flat, rectangular pointing device that is sensitive to pressure and motion Pointing Stick – pressure-sensitive pointing device shaped like a pencil eraser

WHAT ARE INPUT DEVICES? Pointing Devices Trackball Like a mouse, but the ball is on top Often used on portable computers

WHAT ARE INPUT DEVICES? Pointing Devices Joystick Wheel Uses the movement of a vertical lever Often used with games Wheel Steering-wheel type input device Used to simulate driving a car

WHAT ARE INPUT DEVICES? Pointing Devices Touch screen Monitor has a touch sensitive panel Used to issue simple commands or choose from a list of options Kiosks

WHAT ARE INPUT DEVICES? Optical Readers Uses light to read characters, marks, and codes and then converts them into digital data that can be processed by a computer Optical character recognition (OCR) Reads character printed in OCR font Optical mark recognition (OMR) Bar code

WHAT ARE INPUT DEVICES? Optical Scanner Electronically captures an entire page of text or images Converts text or image into digital data than can be stored and used

WHAT ARE INPUT DEVICES? Digital Cameras Allows you to take pictures and store the photographed images digitally Download, or transfer, pictures to your computer

WHAT ARE INPUT DEVICES? Audio and Video Input Audio input Entering music, speech, or sound effects Sound card Speech Recognition Computer’s capability of distinguishing spoken words

WHAT ARE INPUT DEVICES? Audio and Video Input Video input Entering a full-motion recording into a computer and storing the video on a hard disk or some other medium Video capture card

WHAT ARE INPUT DEVICES? Input Devices for Handheld Computers Stylus Voice Input Portable keyboard On screen keyboard

WHAT ARE INPUT DEVICES? Input Devices for Students with Special Needs Americans with Disabilities Act (ADA) Keyguard Touch window Pointing devices

WHAT IS OUTPUT? Data that has been processed into information Text Graphics Audio Video

WHAT ARE OUTPUT DEVICES? Any computer component capable of conveying information to the user

WHAT ARE OUTPUT DEVICES? Monitors and Display Devices Screen housed in a plastic or metal case Variety of sizes Cathode ray tube (CRT) Pixels LCD (liquid crystal display) monitors

WHAT ARE OUTPUT DEVICES? Large Display Monitors Allow an audience or a group of students in a classroom to easily view images and multimedia displayed on a computer Available from 27 to 36 inches

WHAT ARE OUTPUT DEVICES? Large Display Monitors High-definition television (HDTV) Gas plasma monitor

WHAT ARE OUTPUT DEVICES? Flat Panel Monitors and Displays Uses liquid crystal instead of a CRT Consume less than 1/3 the power of a CRT Thinner and lighter than a CRT E-books

WHAT ARE OUTPUT DEVICES? Monitor Quality Resolution (sharpness and clarity) Expressed as number of columns and rows 640 x 480 800 x 600 1024 x 768 Dot pitch Refresh rate ENERGY STAR

WHAT ARE OUTPUT DEVICES? Printers An output device that produces text and graphics on a physical medium such as paper or transparency film Hard copy (printout) Portrait vs. landscape Printing requirements vary

WHAT ARE OUTPUT DEVICES? Impact Printers Printing mechanism strikes ink ribbon forming character on paper Not usually high quality Dot-matrix printers Continuous-form paper

WHAT ARE OUTPUT DEVICES? Nonimpact Printers Do not strike paper Much quieter Ink-jet printers Spray tiny drops of ink onto the paper Both black-and-white and color

WHAT ARE OUTPUT DEVICES? Nonimpact Printers Laser printers High-speed, high-quality nonimpact printer Very high quality resolution – 300dpi to 1,200 dpi

WHAT ARE OUTPUT DEVICES? Data Projectors Allows an audience to view output LCD projectors Digital light processing (DLP) projector

WHAT ARE OUTPUT DEVICES? Facsimile (Fax) Machine Used to transmit and receive an image of a document over a phone line Stand-alone Fax modem

WHAT ARE OUTPUT DEVICES? Multifunction Devices Can print, scan, copy and fax Less space Lower cost than separate units

WHAT ARE OUTPUT DEVICES? Audio Output Produce music, speech, or other sounds Speakers Headsets

WHAT ARE OUTPUT DEVICES? Output Devices for Students with Special Needs Display instead of sound for hearing impaired Change color and magnification on screen Braille printer

WHAT IS STORAGE? The media on which data, instructions, and information are kept The devices that record and retrieve data, instructions, and information Like a filing cabinet

WHAT IS STORAGE? Storage Media and Devices Storage medium Also called secondary storage Physical material Storage device Mechanism used to record and retrieve Capacity measured in megabytes or gigabytes

WHAT IS STORAGE? Floppy Disks Portable, inexpensive storage medium consisting of a thin, circular, flexible film enclosed in a square- shaped plastic shell Several sizes 8-inch 5.25-inch 3.5-inch

WHAT IS STORAGE? Characteristics of a Floppy Disk Uses magnetic patterns to store data Formatting Track Sector Write-protection Guidelines for floppy disk care Floppy disk drive

WHAT IS STORAGE? High-Capacity Removable Disks Capacities greater than 100 MB Many uses Graphics, audio, or video Transporting files Backups Zip drive

WHAT IS STORAGE? Hard Disks Provide large storage capacity and high speed data access Sizes range from 30 GB to 100 GB Consists of several inflexible, circular disks, called platters Magnetic storage device Formatting

WHAT IS STORAGE External and Removable Hard Disks External Hard Disk – Separate hard disk that connects to a USB or FireWire port by cable USB Drives

WHAT IS STORAGE? CDs and DVDs Optical storage media Used to distribute software Laser reads pits on the surface Used on multimedia computers Several types CD-ROM DVD-ROM

WHAT IS STORAGE? Care of CDs and DVDs Can last from 5 to 100 years if properly cared for Never bend a disc Avoid extreme temperatures and humidity Keep away from contaminants Do not stack or touch discs Use a protective case

WHAT IS STORAGE? CD-ROM Compact disc read-only memory Can contain text, graphics, video, as well as sound Can hold 650 MB of data Used for today’s complex software

WHAT IS STORAGE? CD-R and CD-RW Compact disc-recordable Can write on each part of the disc only one time Cannot be erased Compact disc-rewriteable Can write on multiple times Erasable disc

WHAT IS STORAGE? DVD-ROM and DVD+RW Digital video disc read-only memory (DVD-ROM) Can store from 4.7 GB to 17 GB High quality DVD-ROM drives May replace CDs, VCRs, and VHS tapes Digital video disc+rewritable (DVD+RW) Can write on multiple times Erasable disc

WHAT IS STORAGE? Miniature Mobile Storage Media

CHAPTER SUMMARY Describe the system unit Define the term bit, and describe how a series of bits are used to represent data Identify the major components of the system unit and explain their functions Explain how the CPU uses the four steps of a machine cycle to process data

CHAPTER SUMMARY Describe the four types of input and input devices List the characteristics of a keyboard and identify various types of keyboards Identify various types of pointing devices Differentiate among the four types of output Identify the different types of output devices

CHAPTER SUMMARY Explain the differences among various types of printers Differentiate between storage and memory Identify types of storage media and devices Explain how data is stored on floppy disks, hard disks, and CD-ROMs Differentiate between CD-ROMs and DVD-ROMs

Chapter 4 Complete

HOW TO PURCHASE, INSTALL, AND MAINTAIN A PERSONAL COMPUTER Buyer’s Guide 2004 HOW TO PURCHASE, INSTALL, AND MAINTAIN A PERSONAL COMPUTER

HOW TO PURCHASE A PERSONAL COMPUTER Do you want a desktop or mobile computer? For what purposes will you use this computer? Should the computer be compatible with the computers at school or work? Should the computer be a Mac or PC?

HOW TO PURCHASE A DESKTOP COMPUTER Determine the specific software you want to use on your computer Look for bundled software Avoid buying the least powerful computer available Consider upgrades to the mouse, keyboard, monitor, printer, microphone, and speakers Determine whether you want to use telephone lines or broadband (cable or DSL) to access the Internet

HOW TO PURCHASE A DESKTOP COMPUTER If you are using a dial-up or wireless connection to connect to the Internet, then select an ISP or OSP Use a worksheet to compare computers, services, and other considerations If you are buying a new computer, you have several purchasing options: buying from your school bookstore, a local computer dealer, a local large retail store, or ordering by mail via telephone or the Web If you are buying a used computer, stay with name brands such as Dell, Gateway, Hewlett-Packard, and Apple If you have a computer and are upgrading to a new one, then consider selling or trading in the old one

HOW TO PURCHASE A DESKTOP COMPUTER Be aware of hidden costs Consider more than just price Avoid restocking fees Consider purchasing an extended warranty or service plan Use a credit card to purchase your new computer

HOW TO PURCHASE A NOTEBOOK COMPUTER Purchase a notebook computer with a sufficiently large active-matrix screen Experiment with different keyboards and pointing devices Make sure the notebook computer you purchase has a CD and/or DVD drive If necessary, upgrade the processor, memory, and disk storage at the time of purchase The availability of built-in ports on a notebook computer is important

HOW TO PURCHASE A NOTEBOOK COMPUTER If you plan to use your notebook computer for note-taking at school or in meetings, consider a notebook computer that converts to a Tablet PC Consider purchasing a notebook computer with a built-in wireless card to connect to your home network If you are going to use your notebook computer for long periods without access to an electrical outlet, purchase a second battery Purchase a well-padded and well-designed carrying case

HOW TO PURCHASE A NOTEBOOK COMPUTER If you travel overseas, obtain a set of electrical and telephone adapters If you plan to connect your notebook computer to a video projector, make sure the notebook computer is compatible with the video projector For improved security, consider a fingerprint scanner

HOW TO PURCHASE A TABLET PC Make sure the Tablet PC fits your mobile computing needs Decide whether you want a convertible or pure Tablet PC Be sure the weight and dimensions are conducive to portability Port availability, battery life, and durability are even more important with a Tablet PC than they are with a notebook computer

HOW TO PURCHASE A TABLET PC Experiment with different models of the Tablet PC to find the digital pen that works best for you Check out the comfort level of handwriting in different positions Make sure the LCD display device has a resolution high enough to take advantage of Microsoft’s ClearType technology Test the built-in Tablet PC microphone and speakers

HOW TO PURCHASE A TABLET PC Consider a Tablet PC with a built-in PC video camera Review the docking capabilities of the Tablet PC Wireless access to the Internet and your e-mail is essential with a Tablet PC Review available accessories to purchase with your Tablet PC

HOW TO PURCHASE A PDA Determine the programs you plan to run on your PDA Consider how much you want to pay Determine whether you need wireless access to the Internet and e-mail or mobile telephone capabilities with your PDA Make sure your PDA has enough memory

HOW TO PURCHASE A PDA Practice with the touch screen, handwriting recognition, and built-in keyboard before deciding on a model Decide whether you want a color display Compare battery life Even with PDAs, seriously consider the importance of ergonomics

HOW TO PURCHASE A PDA Check out the accessories Decide whether you want additional functionality Determine whether synchronization of data with other PDAs or personal computers is important

HOW TO INSTALL A COMPUTER Read the installation manuals before you start to install your equipment Do some additional research Set up your computer in a well-designed work area and remain aware of health issues as you work Install your computer in a work space where you can control the temperature and humidity

HOW TO INSTALL A COMPUTER Set up your work space near an available electrical outlet and set aside a proper location for the electrical wires Have a telephone outlet and telephone or cable connection near your work space so you can connect your modem and/or place calls while using your computer If you plan to set up a wireless network, choose an area that is free from potential signal interference Install bookshelves

HOW TO INSTALL A COMPUTER Obtain a computer tool set Save all the paperwork that comes with your computer Record the serial numbers of all your equipment and software Complete and mail your equipment and software registration cards or register online

HOW TO INSTALL A COMPUTER Keep the shipping containers and packing materials for all your equipment Identify device connectors Keep your computer area clean Check your home or renter’s insurance policy

HOW TO MAINTAIN YOUR COMPUTER Start a notebook or file using a simple outline that includes information about your computer Before you work inside your computer, turn off the power and disconnect the equipment from the power source Keep the area surrounding your computer dirt and dust free Back up important files and data

HOW TO MAINTAIN YOUR COMPUTER Protect your computer from viruses Keep your computer tuned Learn to use diagnostic tools Conserve energy wherever possible