Computers © 2005 Prentice-Hall, Inc.Slide 1

Computers Chapter 5 Storage and Input/Output Devices © 2005 Prentice-Hall, Inc.Slide 2

Computers Chapter 5 – Storage and Input/Output Devices Objectives Understand the various types of magnetic disk storage devices Understand the various types of optical laser disc storage devices Understand common input devices Understand common output devices © 2005 Prentice-Hall, Inc.Slide 3

Computers Storage and Input/Output Devices Mass Storage Magnetic Disk Tape Optical laser © 2005 Prentice-Hall, Inc.Slide 4

Computers Storage and Input/Output Devices Access Random or direct access Computer can go directly to the desired information (magnetic disk/optical laser disc) Sequential access – data in front of the desired data must be read first (magnetic tape) © 2005 Prentice-Hall, Inc.Slide 5

Computers Storage and Input/Output Devices Type of Magnetic Disks Interchangeable – can be moved from computer to computer Fixed – stays with one computer © 2005 Prentice-Hall, Inc.Slide 6

Computers Storage and Input/Output Devices Type of Magnetic Disks Offline – not available to the computer system Online – available to the computer system © 2005 Prentice-Hall, Inc.Slide 7

Computers Storage and Input/Output Devices Interchangeable Disks Floppy disk – 1.44 MB SuperDisk – 120 MB Zip disk – 100,250,700 MB © 2005 Prentice-Hall, Inc.Slide 8

Computers Storage and Input/Output Devices Interchangeable Disks Disk Density – number of bits that can be stored per unit of area on the disk- face surface © 2005 Prentice-Hall, Inc.Slide 9

Computers Storage and Input/Output Devices Care of Interchangeable Disks Avoid extreme temperatures Avoid direct sunlight and magnetic fields Only remove disks when drive light is off Never force a disk into a drive Do not touch the surface of the disk © 2005 Prentice-Hall, Inc.Slide 10

Computers Storage and Input/Output Devices The Hard Disk Read/write head – accesses or places data on the disk Access arms – where the read/write heads are mounted © 2005 Prentice-Hall, Inc.Slide 11

Computers Storage and Input/Output Devices The Hard Disk Portable hard disk – connects to a computer through a USB or FireWire port © 2005 Prentice-Hall, Inc.Slide 12

Computers Storage and Input/Output Devices Disk Organization Tracks Concentric circles on the disk where data is stored Track density – tracks per inch (TPI) Recording density – megabits per inch © 2005 Prentice-Hall, Inc.Slide 13

Computers Storage and Input/Output Devices Disk Organization Sectors Sector organization Sector – pie-shaped area Clusters – adjacent sectors © 2005 Prentice-Hall, Inc.Slide 14

Computers Storage and Input/Output Devices Disk Organization Disk address – number of the first cluster in a file Cylinder – same-numbered tracks on each recording surface Zone recording – tracks grouped into zones © 2005 Prentice-Hall, Inc.Slide 15

Computers Storage and Input/Output Devices File Allocation Table Virtual File Allocation Table (VFAT) – keeps track of where each cluster can be found on the disk © 2005 Prentice-Hall, Inc.Slide 16

Computers Storage and Input/Output Devices Maintaining the Disk ScanDisk – searches the disk for lost clusters Defragmentation – reorganizes the disk © 2005 Prentice-Hall, Inc.Slide 17

Computers Storage and Input/Output Devices Preparing the Disk for Use Formatting – sets up disk for use on a particular operating system Creates sectors and tracks Creates an area for the VFAT © 2005 Prentice-Hall, Inc.Slide 18

Computers Storage and Input/Output Devices Disk Speed Access time – the interval between when a computer makes a request for data to be transferred and when the operation is completed © 2005 Prentice-Hall, Inc.Slide 19

Computers Storage and Input/Output Devices Disk Speed Data transfer rate – how fast data is transferred from RAM to storage or from storage to RAM Disk caching – using RAM to store some software that will likely be needed © 2005 Prentice-Hall, Inc.Slide 20

Computers Storage and Input/Output Devices Virtual Memory Operating system breaks programs into pages. Only pages being used are placed in RAM. © 2005 Prentice-Hall, Inc.Slide 21

Computers Storage and Input/Output Devices CD-ROM CD (compact disc) – originally used for recording music CD-ROM (compact disc – read-only memory) – user may read, but can’t change information CD-ROM holds up to 650 MB © 2005 Prentice-Hall, Inc.Slide 22

Computers Storage and Input/Output Devices DVD-ROM DVD (digital video disc) Stores 7 to 14 times as much as a CD DVD drives are backward compatible – they will read CDs and CD-ROMs © 2005 Prentice-Hall, Inc.Slide 23

Computers Storage and Input/Output Devices Rewritable Optical Laser Disc Options CD-R (compact disc-recordable) – user may record data, but can’t change it CD-RW (compact disc-rewritable) – user may record data and change it as needed © 2005 Prentice-Hall, Inc.Slide 24

Computers Storage and Input/Output Devices Optical Discs in Your PC DVD-ROM/CD-RW combination drive DVD+RW/CD-RW combination drive – allows for recording of original videos to DVD © 2005 Prentice-Hall, Inc.Slide 25

Computers Storage and Input/Output Devices Other Storage Options Flash memory – low-cost, solid-state memory Mini USB drive Plugs into a computer’s USB port About the size of your thumb © 2005 Prentice-Hall, Inc.Slide 26

Computers Storage and Input/Output Devices Input and Output Devices Input device – converts our commands and data into a form a computer can understand Output device – converts computer data into a form humans can understand © 2005 Prentice-Hall, Inc.Slide 27

Computers Storage and Input/Output Devices The Keyboard Traditional alphanumeric keyboard QWERTY Special-function keyboard Fast-food cash registers © 2005 Prentice-Hall, Inc.Slide 28

Computers Storage and Input/Output Devices The Mouse Used in a GUI (Graphical User Interface) Point and select (click) Mouse pointer – cursor © 2005 Prentice-Hall, Inc.Slide 29

Computers Storage and Input/Output Devices Other Pointing Devices Trackpad Used mostly on notebook computers Move your finger over the touch-sensitive pad Trackpoint – similar to a miniature joystick Trackball – similar to an upside-down mouse © 2005 Prentice-Hall, Inc.Slide 30

Computers Storage and Input/Output Devices Other Pointing Devices Joystick – vertical stick used to move the pointer Digitizer tablet and pen – allow for the digitizing of images © 2005 Prentice-Hall, Inc.Slide 31

Computers Storage and Input/Output Devices Scanners Scanners convert printed matter into a format that can be stored in a computer © 2005 Prentice-Hall, Inc.Slide 32

Computers Storage and Input/Output Devices Scanners for Source Data Automation Handheld label scanner or wand scanner Stationary label scanner Document scanner Turnaround document © 2005 Prentice-Hall, Inc.Slide 33

Computers Storage and Input/Output Devices Bar Code UPC – Universal Product Code © 2005 Prentice-Hall, Inc.Slide 34

Computers Storage and Input/Output Devices OCR Technology OCR (optical character recognition) – scans characters into a computer MICR (magnetic-ink character recognition) – used in banking industry OMR (optical mark recognition) – used to grade tests or questionnaires © 2005 Prentice-Hall, Inc.Slide 35

Computers Storage and Input/Output Devices Image Scanners Image scanner – capable of translating text or images into a form a computer can read Image processing – manipulating scanned images © 2005 Prentice-Hall, Inc.Slide 36

Computers Storage and Input/Output Devices Page and Hand Image Scanners Page image scanner – works like a copy machine Hand image scanner – manually rolled over the image to be scanned © 2005 Prentice-Hall, Inc.Slide 37

Computers Storage and Input/Output Devices Magnetic Stripes Magnetic stripes like the ones on credit cards Badge reader – device to read an employee’s badge to determine clearance © 2005 Prentice-Hall, Inc.Slide 38

Computers Storage and Input/Output Devices Smart Card Can store information or money © 2005 Prentice-Hall, Inc.Slide 39

Computers Storage and Input/Output Devices Speech Recognition Speaker-dependent – can interpret spoken words from only one person Speaker-independent – will accept words from anyone, but has a limited vocabulary © 2005 Prentice-Hall, Inc.Slide 40

Computers Storage and Input/Output Devices Digicams Digital camera – records images digitally Digital video camera – captures motion video Webcams – digital video cameras connected to the Internet © 2005 Prentice-Hall, Inc.Slide 41

Computers Storage and Input/Output Devices Digicams Digital camcorder – captures video digitally Video capture card – expansion card that allows for the capture of video to disk © 2005 Prentice-Hall, Inc.Slide 42

Computers Storage and Input/Output Devices Handheld and Wearable Data Entry Devices Limited keyboard Small touch-sensitive display Storage capability – probably solid- state Scanning device capable of OCR © 2005 Prentice-Hall, Inc.Slide 43

Computers Storage and Input/Output Devices Monitors CRT monitor – takes up a great deal of space Flat-panel monitor – found on notebook PCs and some desktops; much smaller than CRT monitors © 2005 Prentice-Hall, Inc.Slide 44

Computers Storage and Input/Output Devices Flat-Panel Monitors LCD (liquid crystal display) Active matrix – more brilliant display, also called TFT (thin film transistor) Passive matrix © 2005 Prentice-Hall, Inc.Slide 45

Computers Storage and Input/Output Devices Monitors Graphics adapter – monitor’s device controller Video Ram or VRAM – memory on the graphics adapter where images are prepared for display on the monitor © 2005 Prentice-Hall, Inc.Slide 46

Computers Storage and Input/Output Devices Monitors Dual monitor – high-end graphics adapters, allow for multiple monitors to be connected to one PC © 2005 Prentice-Hall, Inc.Slide 47

Computers Storage and Input/Output Devices Monitor Size Measured diagonally 5 to 60 inches © 2005 Prentice-Hall, Inc.Slide 48

Computers Storage and Input/Output Devices Monitor Resolution Resolution depends on: Number of pixels that can be displayed Number of bits used to represent a pixel Dot pitch of the monitor © 2005 Prentice-Hall, Inc.Slide 49

Computers Storage and Input/Output Devices Monitor Resolution Pixel (picture element) – a dot on the screen Gray scales – number of shades of a color that can be displayed © 2005 Prentice-Hall, Inc.Slide 50

Computers Storage and Input/Output Devices Monitor Resolution RGB monitor – creates colors by combining red, green, and blue Color depth – number of bits used to represent a pixel Dot pitch – distance between the centers of adjacent pixels © 2005 Prentice-Hall, Inc.Slide 51

Computers Storage and Input/Output Devices Monitors Touch screen monitor – user indicates choice by touching the screen LCD projector – allows the user to project what is on the computer monitor onto a large screen for an audience © 2005 Prentice-Hall, Inc.Slide 52

Computers Storage and Input/Output Devices Printers Laser printer – prints a page at a time Ink-jet printer – ink is sprayed onto paper to form characters and images Large-format ink-jet printer – used to create large documents such as blueprints © 2005 Prentice-Hall, Inc.Slide 53

Computers Storage and Input/Output Devices Printers All-in-one multifunction device – has all of the capabilities of a printer, fax machine, scanner, and copier © 2005 Prentice-Hall, Inc.Slide 54

Computers Storage and Input/Output Devices Sound Sound card Speaker system © 2005 Prentice-Hall, Inc.Slide 55

Computers Storage and Input/Output Devices Voice Output Voice Response System Reproduction of a human voice Speech synthesis Speech synthesis system – converts data into electronic speech Text-to-speech software – produces speech by combining phenomes © 2005 Prentice-Hall, Inc.Slide 56

Computers Chapter 5 – Storage and Input/Output Devices Lesson Summary Understand the various types of magnetic disk storage Understand the various types of optical laser disc storage Understand common input devices Understand common output devices © 2005 Prentice-Hall, Inc.Slide 57