copyright 2002, paradigm publishing inc. hardware: enabling the information processing cycle
Post on 26-Dec-2015
218 Views
Preview:
TRANSCRIPT
2 - 2
Copyright 2002, Paradigm Publishing Inc.
Topics
Topics
System Unit Hardware
Input Hardware
Output Hardware
Storage Devices
Large Computer Hardware
On the Horizon
2 - 3
Copyright 2002, Paradigm Publishing Inc.
Topics
Embedded Computer
A specialized computer that is part of a larger system, device, or machineTiny circuit boards (chips) that are essential to the operation of the device– contain instructions that enable the device
to function properly
Use continues to expand with increasing Internet use and desire for mobile access
2 - 4
Copyright 2002, Paradigm Publishing Inc.
Topics
What is Hardware?
all of the physical devices or equipment you can seethat make up a computerized system
all of the physical devices or equipment you can seethat make up a computerized system
larger and more complex system requireslarger number of devices to support its functions
larger and more complex system requireslarger number of devices to support its functions
2 - 5
Copyright 2002, Paradigm Publishing Inc.
Topics
System Unit Hardware
main part of a PC system
contains components necessary for processing information
2 - 6
Copyright 2002, Paradigm Publishing Inc.
Topics
The Motherboard
A thin sheet of fiberglass with electrical pathways (traces) etched to connect components
microprocessor
system clock
sockets for RAM
ROM chips
expansion slots
ports
buses
power supply
2 - 7
Copyright 2002, Paradigm Publishing Inc.
Topics
Microprocessors
Also referred to as a central processing unit (CPU) or the brainElectronic chips are also called integrated circuits
2 - 8
Copyright 2002, Paradigm Publishing Inc.
Topics
RAM Chips
Also called main memoryMain memory consists of a group of electronic chips inside the system unit– stores programs while they are being
executed– stores data while it is being processed
Large programs require lots of main memory– additional chips can be installed
2 - 9
Copyright 2002, Paradigm Publishing Inc.
Topics
Measuring RAM Capacities
Computer MemoryComparisons
2 - 10
Copyright 2002, Paradigm Publishing Inc.
Topics
Cache Memory
Secondary type of processing storage used with RAM– holding area where most recently called instructions
and data are stored– shortens processing time
Level 1built into
the architecture
Level 2same as Level 1 or
may consist of high-speedSRAM chips on motherboard
2 - 11
Copyright 2002, Paradigm Publishing Inc.
Topics
ROM Chips
Contain instructions or data permanently placed on the chip by the manufacturerCan only be read, not altered or erased, and are nonvolatile (do not need constant power supply) BIOS
basic input/output systemprogram that boots the computer and
communicates with components
BIOSbasic input/output system
program that boots the computer andcommunicates with components
POSTpower-on self test
contains instructions to check physical components
POSTpower-on self test
contains instructions to check physical components
2 - 12
Copyright 2002, Paradigm Publishing Inc.
Topics
Other System Unit HardwarePort– external plug-in slot used
to connect a device– serial, parallel, video,
USB, SCSI– docking station is an
accessory that provides additional ports
Expansion slot– slot is an opening to allow
insertion of a board– sound, video, network
interface, graphics, modem
PC Card– plugs into a portable
computer– Type I = additional
memory– Type II = network or
sound– Type III = removable hard
drive
Bus– electronic path along
which bits are transmitted
– size is referred to as bus bandwidth
2 - 13
Copyright 2002, Paradigm Publishing Inc.
Topics
Input Hardware
the hardware device that allows users toenter programs, data, and commands
the hardware device that allows users toenter programs, data, and commands
the program or application being used determinesthe type of input device needed
the program or application being used determinesthe type of input device needed
2 - 14
Copyright 2002, Paradigm Publishing Inc.
Topics
Alphanumeric Keyboard
special-purpose keys
function keys numeric keypad
cursor-control keys
2 - 15
Copyright 2002, Paradigm Publishing Inc.
Topics
Special-Purpose Keyboard
used by businessesto increase user
efficiency
2 - 16
Copyright 2002, Paradigm Publishing Inc.
Topics
Mouse
make selections from a menu and activate programs
optical mouseuses a light
sensorto track
movementfoot mouse
for people with hand
and wrist injuries
mouse pad
2 - 17
Copyright 2002, Paradigm Publishing Inc.
Topics
Trackball
Similar to a mouse (upside-down)Remains stationary – user moves the ball to move the pointer on the screenRequires less desk space and arm movement
2 - 18
Copyright 2002, Paradigm Publishing Inc.
Topics
Touch Pad and Touch ScreenTouch Pad
Small, flat device sensitive to touch, pressure, motionOne part acts as a button; other functions like the surface of a mouse padUsed in many portable computers
Touch ScreenAllows user to make selections by pressing finger against the chosen option on the screenUsed in ATMs and kiosks at retail outlets
2 - 19
Copyright 2002, Paradigm Publishing Inc.
Topics
Joystick
Small box containing a vertical leverMoves the cursor on the screen when pushed in a certain directionOften used for computer gamesPointing lever is a new type used for notebooks– eliminates external mouse or
joystick– allows hand to remain close to
keyboard
2 - 20
Copyright 2002, Paradigm Publishing Inc.
Topics
Pen and Tablet
Digitizing pen with drawing tablet is used when precise control over an input device is requiredPDAs use a special pen– choose menu options – write information on
the screen
Graphics tablet used to trace precise or detailed drawings– hundreds of intersecting
wires are embedded in the flat surface
– intersection represents specific location (address) with values of 0 and 1 (1 when touched by pen)
2 - 21
Copyright 2002, Paradigm Publishing Inc.
Topics
Optical Scanner
A light-sensing electronic deviceUses lasers to read and capture printed text and images and stores as a fileMatrix of rows and columns of dots called a bitmapQuality is determined by the resolution– each dot consists of one or more bits of data; the more
bits, the clearer the image– higher number of dots (pixels) per inch (dpi) results in
sharper and clearer image– home/office models use a resolution of at least 1,200 dpi
2 - 22
Copyright 2002, Paradigm Publishing Inc.
Topics
Optical Scanner…/2Intelligent scanner– uses optical character
recognition (OCR) software so changes can be made
Dumb scanner– can only capture and input
Handheld scanner– moves the scanner across
the materialFlatbed scanner– pages are laid on the
scanner’s surface (or fed through) and the device inside moves
2 - 23
Copyright 2002, Paradigm Publishing Inc.
Topics
Optical Scanner…/3
Bar code reader – common for commercial use with a Universal Product Code (UPC)– form of a pen or placed below a glass cover– computer uses number to locate information
about the product like name or price
Optical reader – to pay for purchases– cash cards – store cash in digital form– smart cards – contain electronic memory
(store cash, as well as other information)
2 - 24
Copyright 2002, Paradigm Publishing Inc.
Topics
Audio Input
process of entering (recording)speech, music, or sound effects
must have sound card, sound capturing device,speakers, and special software
voice recognitionrecognizes preprogrammed wordsstored in a database by different individuals (speaker-independent)
speech recognitionrecords speech in digital form in a
database that can be used again usually by the same person (speaker-dependent)
2 - 25
Copyright 2002, Paradigm Publishing Inc.
Topics
Video Input
Uses a special type of video camera that is plugged into a video capture card– converts the analog video signal to a digital
signal
Video can also be live or recorded using a video camera and a special processing boardBusinesses, government, and organizations are discovering numerous video-input applications
2 - 26
Copyright 2002, Paradigm Publishing Inc.
Topics
Digital CameraCaptures and stores an image in a digital format– flash memory– floppy disk
Photo-editing software available to adjust color and sizeQuality is measured by resolution (same as scanners)– usually advertised in
megapixels (millions of pixels)
2 - 27
Copyright 2002, Paradigm Publishing Inc.
Topics
Output Hardware
hard copypermanent version
(printout)
soft copytemporary version(display on screen)
processed data that can beused or stored
2 - 28
Copyright 2002, Paradigm Publishing Inc.
Topics
Cathode Ray Tube (CRT) Monitor
Most common type– large, sealed glass tube housed in a plastic case– front of the tube is the screen, cable at the rear of
monitor plugs into graphics adapter board, electric cord into outlet
RGB – Red, Green, Blue– contained in each dot of phosphor material on screen– three dots make up a pixel– electron beam moves back and forth across rear of
screen causing dots on front to glow
Video card converts digital signals to analog signals
2 - 29
Copyright 2002, Paradigm Publishing Inc.
Topics
Flat-Panel Display
Smaller, lighter, thinner, and consumes less powerLiquid crystal display (LCD)– liquid crystals are sandwiched between
sheets of material– electric current passes through crystals,
causes them to twist– effect blocks some light waves and allows
others to pass through– uses digital signals
2 - 30
Copyright 2002, Paradigm Publishing Inc.
Topics
Display Goggles
Effective for computer games Allow mobile workers to perform without having to stop to use a computer (hands-free)Data and information are displayed on a headset-mounted full-color video console
2 - 31
Copyright 2002, Paradigm Publishing Inc.
Topics
Most common device for hard-copy outputCategories– impact – strikes an inked ribbon against the paper– nonimpact – uses electricity, heat, laser technology,
or photographic techniques to form images
Three types include a range of printers that vary in quality of output and printing speed
Printers
2 - 32
Copyright 2002, Paradigm Publishing Inc.
Topics
Dot-Matrix PrintersTiny dots form imagesPrint head strikes inked ribbon, deposits on pageResolution measured in dpi– draft or letter quality
Print head contains pins– more pins = higher quality
Prints one character at a time– speed measured by cps
Capable of printing multi-part forms
2 - 33
Copyright 2002, Paradigm Publishing Inc.
Topics
Ink-Jet Printers
Sprays thousands of tiny droplets of electrically charged ink to form imagesResolution measured in dpiSpeed measured in ppm
2 - 34
Copyright 2002, Paradigm Publishing Inc.
Topics
Laser PrintersExceptional qualityMechanism reads characters and sends to laser deviceLaser sends light signals through mirrors in the drum, creating tiny dots of lightDots create magnetic fields on drum (matches shape) which attracts toner powerToner pressed onto paper as drum rotates
2 - 35
Copyright 2002, Paradigm Publishing Inc.
Topics
Plotters
To produce specialized kinds of large-sized, high-quality printingImage consists of a series of tightly packed tiny dotsToner is fused onto paper when electrically charged wires come into contact with specially coated paper
2 - 36
Copyright 2002, Paradigm Publishing Inc.
Topics
Speakers
Speakers
warning sounds computer games audio e-mail distance learning videoconferencing
2 - 37
Copyright 2002, Paradigm Publishing Inc.
Topics
Storage Devices
Permanent storage consists of devices and media used for permanent recordings– also called secondary, auxiliary, or external storage
Consists of two main parts– storage device
• hardware component that houses a storage medium
– storage medium• where data is recorded
Usually built into a PC systemTwo main types– magnetic– optical
2 - 38
Copyright 2002, Paradigm Publishing Inc.
Topics
Categories– permanent – attached to
system unit (e.g. hard disk)
– removable – can be removed/replaced (e.g. floppy disk)
How stored data is accessed– sequentially – in the order
in which data was stored– directly – in any order,
randomly
Access time– time spent locating a file
Data transfer rate– speed at which data is
transferred from memory or storage device
Work by applying electrical charges to iron filings on the surface medium– either magnetized (1-bit)
or not magnetized (0-bit)
Magnetic Storage Devices
2 - 39
Copyright 2002, Paradigm Publishing Inc.
Topics
Floppy Disks and Disk Drives
A thin, circular Mylar wafer between two sheets of special cleaning tissue inside a plastic caseData is stored along tracks and sectors– track – a numbered concentric circle– sector – a numbered section or portion; group = cluster
Computer maintains a file directory of the file name, size, and sector in which the file begins– called a file allocation table (FAT file)
Higher-capacity floppy disks– SuperDisk, Zip, HiFD
2 - 41
Copyright 2002, Paradigm Publishing Inc.
Topics
Formatting a Floppy Disk
Must be formatted by manufacturer or userHow a disk is formatted is determined by disk drive and operating systemDisk surface is arranged into– tracks– sectors– clusters
2 - 43
Copyright 2002, Paradigm Publishing Inc.
Topics
Hard Disks and Hard DrivesConsist of– one or more rigid metal
platters (disks) – disks mounted on a
metal shaft in a container
– an access mechanism
Sealed to prevent contaminationFixed or interchangeable– Jaz cartridge
Usually preformatted– can be reformatted
2 - 44
Copyright 2002, Paradigm Publishing Inc.
Topics
Comparing Floppy Disks and Hard Drives
Floppy Disksstorage capacity: megabytes
spins only when datais being stored
or accessed
Hard Disksgreater storage capacities:
gigabytesoperates much faster;
rotates fastercontinues spinning whilecomputer is in operation
2 - 45
Copyright 2002, Paradigm Publishing Inc.
Topics
Tape Cartridges and Tape Drives
One of the first typesUsed mainly for – backing up the contents of a hard drive– archiving large amounts of data
Small plastic housing containing a magnetically coated ribbon of thin plasticTape drive is used to read and write dataRelatively inexpensiveSequential-access type of storage
2 - 46
Copyright 2002, Paradigm Publishing Inc.
Topics
Optical disk– also called compact disk (CD)– a plastic disk that is 4.75 inches in diameter
Optical disk drive– can read almost any kind of data recorded
Data stored along a single track in sectors– spirals outward from the center to the outer
edge
Available in a variety of formats– not necessarily compatible with one another
Optical Disks and Disk Drives
2 - 47
Copyright 2002, Paradigm Publishing Inc.
Topics
Types and Storage Capacities of Optical Disks
2 - 48
Copyright 2002, Paradigm Publishing Inc.
Topics
Large Computer Hardware
MagneticDisk pack– mounted inside a disk
drive– metal shaft extends
through center of vertically aligned disks
– provides direct access
Magnetic tape– removable reels– contains tracks that
extend the full length of the tape
– sequential access
OpticalWORM– write once, read many
disks– mainly found in
mainframe applications
– high-capacity– usually only readable
by the drive on which they were written
2 - 49
Copyright 2002, Paradigm Publishing Inc.
Topics
On the Horizon
Wireless, Wireless,and MoreWireless
Increased MagneticData Storage
Capacities
ImprovedMonitors
MoreSmart Cards
BiometricAuthentication
Devices asSecurity Measures
top related