Hardware: Enabling the Information Processing Cycle

1. Hardware: Enabling the Information Processing Cycle Chapter 2

2. Topics System Unit Hardware Storage Devices Input Hardware Large Computer Hardware Output Hardware On the Horizon

3. Embedded Computer • A specialized computer that is part of a larger system, device, or machine • Tiny 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

4. What is Hardware? all of the physical devices or equipment you can see that make up a computerized system larger and more complex system requires larger number of devices to support its functions

5. System Unit Hardware main part of a PC system contains components necessary for processing information

6. The Motherboard • A thin sheet of fiberglass with electrical pathways (traces) etched to connect components microprocessor expansion slots system clock ports sockets for RAM buses ROM chips power supply

7. Microprocessors • Also referred to as a central processing unit (CPU) or the brain • Electronic chips are also called integrated circuits

8. RAM Chips • Also called main memory • Main 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

9. Computer MemoryComparisons Measuring RAM Capacities

10. 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 1 built into the architecture Level 2 same as Level 1 or may consist of high-speed SRAM chips on motherboard

11. ROM Chips • Contain instructions or data permanently placed on the chip by the manufacturer • Can only be read, not altered or erased, and are nonvolatile (do not need constant power supply) BIOS basic input/output system program that boots the computer and communicates with components POST power-on self test contains instructions to check physical components

12. Port 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 Other System Unit Hardware

13. Input Hardware the hardware device that allows users toenter programs, data, and commands the program or application being used determinesthe type of input device needed

14. function keys numeric keypad special-purpose keys cursor-control keys Alphanumeric Keyboard

15. Special-Purpose Keyboard used by businesses to increase user efficiency

16. mouse pad Mouse make selections from a menu and activate programs optical mouse uses a light sensor to track movement foot mouse for people with hand and wrist injuries

17. Similar to a mouse (upside-down) Remains stationary – user moves the ball to move the pointer on the screen Requires less desk space and arm movement Trackball

18. Touch Pad Small, flat device sensitive to touch, pressure, motion One part acts as a button; other functions like the surface of a mouse pad Used in many portable computers Touch Screen Allows user to make selections by pressing finger against the chosen option on the screen Used in ATMs and kiosks at retail outlets Touch Pad and Touch Screen

19. Small box containing a vertical lever Moves the cursor on the screen when pushed in a certain direction Often used for computer games Pointing lever is a new type used for notebooks eliminates external mouse or joystick allows hand to remain close to keyboard Joystick

20. Digitizing pen with drawing tablet is used when precise control over an input device is required PDAs 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) Pen and Tablet

21. Optical Scanner • A light-sensing electronic device • Uses lasers to read and capture printed text and images and stores as a file • Matrix of rows and columns of dots called a bitmap • Quality 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

22. Intelligent 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 material Flatbed scanner pages are laid on the scanner’s surface (or fed through) and the device inside moves Optical Scanner…/2

23. 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)

24. must have sound card, sound capturing device, speakers, and special software voice recognition recognizes preprogrammed words stored in a database by different individuals (speaker-independent) speech recognition records speech in digital form in a database that can be used again usually by the same person (speaker-dependent) Audio Input process of entering (recording) speech, music, or sound effects

25. 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 board • Businesses, government, and organizations are discovering numerous video-input applications

26. Captures and stores an image in a digital format flash memory floppy disk Photo-editing software available to adjust color and size Quality is measured by resolution (same as scanners) usually advertised in megapixels (millions of pixels) Digital Camera

27. Output Hardware processed data that can be used or stored hard copy permanent version (printout) soft copy temporary version (display on screen)

28. 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

29. Flat-Panel Display • Smaller, lighter, thinner, and consumes less power • Liquid 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

30. 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

31. Printers • Most common device for hard-copy output • Categories • 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

32. Tiny dots form images Print head strikes inked ribbon, deposits on page Resolution 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 Dot-Matrix Printers

33. Sprays thousands of tiny droplets of electrically charged ink to form images Resolution measured in dpi Speed measured in ppm Ink-Jet Printers

34. Exceptional quality Mechanism reads characters and sends to laser device Laser sends light signals through mirrors in the drum, creating tiny dots of light Dots create magnetic fields on drum (matches shape) which attracts toner power Toner pressed onto paper as drum rotates Laser Printers

35. Plotters • To produce specialized kinds of large-sized, high-quality printing • Image consists of a series of tightly packed tiny dots • Toner is fused onto paper when electrically charged wires come into contact with specially coated paper

36. Speakers

37. 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 system • Two main types • magnetic • optical

38. 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 • 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

39. Floppy Disks and Disk Drives • A thin, circular Mylar wafer between two sheets of special cleaning tissue inside a plastic case • Data 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

40. How a Floppy Disk Drive Works

41. Must be formatted by manufacturer or user How a disk is formatted is determined by disk drive and operating system Disk surface is arranged into tracks sectors clusters Formatting a Floppy Disk

42. Handling a Floppy Disk

43. Consist of one or more rigid metal platters (disks) disks mounted on a metal shaft in a container an access mechanism Sealed to prevent contamination Fixed or interchangeable Jaz cartridge Usually preformatted can be reformatted Hard Disks and Hard Drives

44. Comparing Floppy Disks and Hard Drives Floppy Disks storage capacity: megabytes spins only when data is being stored or accessed • Hard Disks • greater storage capacities: • gigabytes • operates much faster; • rotates faster • continues spinning whilecomputer is in operation

45. Tape Cartridges and Tape Drives • One of the first types • Used 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 plastic • Tape drive is used to read and write data • Relatively inexpensive • Sequential-access type of storage

46. Optical Disks and Disk Drives • 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

47. Types and Storage Capacities of Optical Disks

48. Magnetic Disk 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 Optical WORM write once, read many disks mainly found in mainframe applications high-capacity usually only readable by the drive on which they were written Large Computer Hardware

49. On the Horizon Improved Monitors Wireless, Wireless, and More Wireless Biometric Authentication Devices as Security Measures More Smart Cards Increased Magnetic Data Storage Capacities

50. Questions?