Chapter 3 Computer Hardware
- 2. CHAPTER HIGHLIGHTS • Computer systems – Supercomputer – Mainframe computer – Personal computer • Computer platforms • Hardware components – System Unit – Peripheral Devices • Computers & Networks – WAN and LAN – Client/Server model 2
- 3. COMPUTER SYSTEMS • An integrated set of hardware and software designed to process data and produce a meaningful result. • Basic functions: – Input – Processing – Storage – Output – Transmission 3
- 4. TYPES OF COMPUTER SYSTEMS • Supercomputer. – Offers the fastest processing speeds and performs the most complex calculations. • Mainframe computer. – Provides multi-user computing to large organizations for tasks such as managing extensive databases, financial transactions, and communications. • Personal computer. – Provides computing to a single user performing multiple tasks. 4
- 5. COMPUTER PLATFORM • Platform is a combination of hardware and operating system. – Windows/PC platform. – Macintosh platform. • Cross-platform compatibility. – Ability of an application to run on different hardware and operating systems. • Adobe's Acrobat .pdf files can be opened on Windows or OS X based computers. – The WWW provides a cross-platform computing experience. 5
- 6. INTERFACE PORTS • Ports are external to the system unit. – Peripherals are plugged into the ports. • Common ports include: – SCSI – VGA or SVGA – USB – IEEE 1394 (FireWire) – Audio input/output – Ethernet and modem connections. 6
- 7. USB & FIREWIRE: The New Standard • Offers Plug and Play performance with most operating systems. • Supports a daisy-chain bus of multiple devices. • Accepted on PCs and Macs. • Has hot-swappable capability. • Powered through the interface port. – No more "wall warts." 7
- 8. PERIPHERAL DEVICES 8 INPUT, OUTPUT, AND PERMANENTLY STORED DATA AND APPLICATIONS.
- 9. SECONDARY STORAGE • Holds data and instructions outside the system unit for long periods of time. • Advantages over primary storage: – Nonvolatile storage – Expandable – Portable – Inexpensive • Options include magnetic, optical, solid-state storage. 9
- 10. SECONDARY STORAGE • Five Main Uses – Saving data during edit process. – Backup data and applications. – Distribute data and applications. – Transport data and applications. – Archive data and applications. 10 Storage Devices Hard drive Floppy drive Zip drive Portable hard drive CD drive DVD drive Flash or thumb drive Magnetic tape drive
- 11. MAGNETIC STORAGE • Bits are stored in magnetic form on disk platters or magnetic tape. • Disk platters are hard or floppy. – Data stored in addressable tracks and sectors defined by the operating system. – Track — circular paths – Sector — pie shaped logical divisions of the track. 11
- 12. MAGNETIC STORAGE • Benefits: – Large storage capacity – Fast access to data – Economical • Challenges: – Limited durability – Easily damaged 12 FYI: The projected cost of a gigabyte of magnetic storage in 2010 is .02 cents.
- 13. OPTICAL STORAGE • Compact Disc (CD) first used to replace vinyl records in music industry. – Stored digital music for permanent, high fidelity recordings. – Capacity set at 74 minutes of digital audio. 13 FYI: Disc refers to optical storage. Disk denotes magnetic storage.
- 14. Compact Disc Formats • Standard physical size: – 120 mm, 15mm hole in the center, 1.2 mm thick. – Led to rapid development of drives to accept all CD formats. • CD-DA (Digital Audio format). • CD-ROM (Read-Only format). • CD-R (Recordable format). • CD-RW (Re-Writable format). 14
- 15. DIGITAL VERSATILE DISC (DVD) • Optical storage that uses: – More precise laser light – Multi-layer storage – New video compression methods – Improved error detection and correction • Result. – Higher storage capacity than compact disc • 650MB on CD (74 minutes of music) • 17GB on DVD (8 hrs of video) 15
- 16. DVD FORMATS • Standards vary by player and data. • DVD recordable formats: – DVD-R: compatible with most players & drives – DVD-RW: playable in many DVD drives and players – DVD-RAM: Removable storage for computers. 16
- 17. BLU-RAY: Next Generation • Optical storage based on blu-ray laser. – Shorter wavelength (405nm). • Massive storage capacity. – Single layer can store 27GB of data. • Can store 2 hours of high-definition video or • 13 hours of standard video. – Dual layer stores 50GB of data. • Currently used for recording high definition video and PlayStation 3 games. 17
- 18. SOLID-STATE STORAGE • Computer storage with no moving parts. • Devices are based on flash memory technology. – Contains a grid of cells, each with two transistors separated by a thin layer of insulating oxide. – The insulating oxide layer preserves information with no need for external power. 18
- 19. SOLID-STATE STORAGE • Benefits: – Lightweight – Small – Low power requirements – More durable than devices with movable parts • Disadvantages: – More expensive than magnetic storage – Limited capacity – Limited life expectancy 19 FYI: Labels for solid state storage devices include: •USB drive •Flash drive •Thumb drive •Memory stick
- 20. SECONDARY STORAGE (Future Digital Data) • Practical issues surrounding the migration of data to secondary storage include: – Effective and efficient data management. – Enduring file formats over the years. – Ability to access the data on the storage media • Hardware requirements • Software dependence – Data longevity. 20
- 21. INPUT DEVICES • Capture and transmit data and instructions to the system used for processing and storage. • Categories: – Keyboard – Pointing devices – Scanning devices – Image capture – Audio capture 21
- 22. INPUT DEVICES • Keyboard. – Capture user text and commands. • Pointing device. – Relies on graphic interface to click or select the input. – Devices include: • Mouse • Pointing stick • Stylus • Touch screens • Touch pads • Trackball 22 FYI: The Wii Remote is also a pointing device for the popular game console. FYI: The Wii Remote is also a pointing device for the popular game console.
- 23. INPUT DEVICES: SCANNER • Captures text or graphics using a light-sensing device called a Charge-Coupled Device (CCD). • Types of scanners include: – Flat bed – Hand held – Sheet fed – Slide • Scanner quality depends on: – Spatial resolution – Color resolution (bit depth) 23
- 24. SCANNER Settings • Spatial Resolution (dpi). – Depends on use of image. • 72 dpi for computer display. • 300 dpi for printer output. • Color resolution (bit depth). – 8 bit setting confines color range to 256. – Grayscale setting uses black, white and shades of gray. • Scaling. – Set the size larger or smaller before the scan. • Tonal quality. – Adjust brightness and contrast based on preview of scan. 24
- 25. SCANNER & OCR • Optical Character Recognition is a process that converts printed text into an editable word processed digital file. – OCR software analyzes the image of a character and translates it to an ASCII code of the character. • OCR quality depends on software, quality of printed text, and type of paper being scanned. – Extensive editing may be required to remove stray characters or misinterpreted text. 25
- 26. DIGITAL CAMERA • Captures images in real time at the source. • Benefits include: – Instant review of image – Re-capture the image if necessary – High quality spatial and color resolution. • Image file size depends on capture resolution (6 - 12 megapixel) and color depth (16 - 24 bit color) can produce large file sizes. • Images transferred to hard drive via memory card or USB direct connection. 26
- 27. DIGITAL VIDEO (DV) CAMERA • Video captured on built-in hard drive, mini-digital tape, or DVD. • Transferred to computer through FireWire interface. • Video editing software enhances digital sequences. 27
- 28. DV CAMERA PERFORMANCE • Method used to capture image. – Single chip reproduces RGB color. – 3-chip have separate CCD for Red, Green, Blue. • Lens quality. • Zoom quality. – Optical zoom vs. digital zoom. • Image stabilization. • Preprogrammed modes. – Lighting and weather conditions. 28
- 29. SOUND CAPTURE • Devices to transform analog waveforms to digital files. – Microphones • External vs. internal – CD & Tape players – Digital Recorders. 29
- 30. GRAPHICS TABLET • Flat drawing surface for freehand image creation. • User draws or traces image with a stylus then enhances the image using software interface. 30
- 31. OUTPUT DEVICES • Present processed data in a useful form. • Devices include: – Screen display – Audio speakers – Hard copy 31
- 32. DISPLAY DEVICES • Produce an image on a screen through a series of individual pixels. – Display quality is determined by spatial and color resolution. – Displays with 1024 X 768 spatial resolution have more addressable pixels than 640 X 480 resolution. – 24-bit color graphics display has richer colors than 16-bit color. 32
- 33. CRT DISPLAY • Raster scanning technology generates a display. – Based on Cathode Ray Tube technology. • Electronic signal scans horizontal rows from top to bottom of screen. 33
- 34. LCD DISPLAY • Transistors control a liquid crystal's molecular structure to display a pixel. • Two forms of LCD: – Active matrix or Thin Film Transistors – Passive matrix • Native display resolution is fixed to specific LCD screen size. – Altering the resolution will generate a blurred image. 34
- 35. SPEAKER SYSTEMS • Speakers or headsets are plugged into the soundboard where digital data is converted to analog waveforms. • Sound card circuitry performs four processes: – Converts digital sound data into analog with DAC. (digital to analog converter) – Records sound in digital form with analog ADC. – Amplifies signal. – Creates digital sounds using a synthesizer. 35
- 36. PRINTERS • Two basic printing technologies: – Impact, print head makes contact with the paper. • Dot-matrix printer. – Nonimpact, print head does not contact paper. • Laser printer. • Ink-jet printer. • Photo printer. 36
- 37. NON-IMPACT PRINTERS • Ink-jet printer. – Line printer that delivers high quality color. – Output quality determined by: • Printer resolution measured in dots/inch • Paper quality • Photo printer. – Delivers photo-lab-quality output directly from camera or card. – Use inkjet cartridges or dye sublimation process to print image. 37
- 38. NON-IMPACT PRINTERS • Laser printer. – Fuse text and image to paper one page at a time. – High quality output resolutions of 600 to 2400 dpi. – Deliver high quality color output using cyan, magenta, yellow, and black toner. • Multifunction printer. – Combines printer, scanning, fax, and copier technology in one device. 38
- 39. NETWORKS • A collection of computers connected through a communication link to share resources. • Two main categories: – WAN - Covers wide geographic area using communication lines of an external service provider. – LAN - Computers and peripherals connected within an organization on privately owned communication lines. 39
- 40. INTERNET • A network of networks built on TCP/IP protocols. – Transfer Control Protocol prepares data in packets to distribute on the network. – Internet Protocol assigns a numeric address to each packet of data. • Common Internet protocols: – eMail — smtp – File transfer — ftp – Web — http 40
- 41. WORLD WIDE WEB — WWW • WWW built on revolutionary http protocol. • Hypertext transfer protocols included: – Html code that programmed text and images on a web document. – Hyperlinks to connect related "pages" on local and external servers. – Uniform Resource Locator (URL) as the path address to create the hyperlink. • URL includes the protocol, domain name of server, directory location, and the document to view, often a .htm or .html page. 41 www.com205.safiredesign.com/index.htmlwww.com205.safiredesign.com/index.html
- 42. NETWORKS • Client/Server organization. – Efficient means to distribute data from the server and rely on processing at the client (local) computer. – Commonly used on LANs and WWW. • Ethernet. – Protocol to control flow of data on LAN. • WiFi & Bluetooth. – Mobile computing network standards. 42
- 43. WRAP UP • Computer systems – Supercomputer – Mainframe – Microcomputer • System unit – CPU – Primary memory – System board • Interface ports – USB – FireWire • Peripherals – Storage devices – Input devices – Output devices • Networks – WAN – LAN – Internet 43
Editor's Notes
- #4: Have students identify purpose of each function and a device that performs the function.
- #6: Have students research other platforms and discuss if they are different platforms or just different operating systems. Discuss the role of the WWW in creating a single computing platform.
- #7: Students should identify the devices for each port and discuss other ports they find on their computers.
- #8: Students should identify the benefits of these ports and also the distinctions between USB and FireWire. Research the current standards for transmission speeds of USB2 and FireWire 800. Identify appropriate uses for each.
- #11: Students should identify the distinction and importance for all these uses. Discussion could include which secondary storage devices are appropriate for each use.
- #12: Floppy disks are marginally supported on most current microcomputers, however there are still drawers full of backup data on floppy disks. While discussion of floppy storage may not enter in the lesson, it does offer a transition to the benefits of hard disk storage. Tape drives are not covered in the text, but should be mentioned as a backup media
- #13: FYI taken from "The Decline of Magnetic Disk Storage Cost over the Next 25 Years " by Steve Gilbeany, located at: www.berghell.com/whitepapers/Storage%20Costs.pdf Students may not appreciate how easy it is to destroy magnetism on a disk. Magnetic fields from radios, TVs, or just extreme heat often destroyed data on floppy disks.
- #14: Have students report why the capacity is set at 74 minutes of digital audio. Originally set at 74 minutes to accommodate a performance of Beethoven’s Symphony Number 9. Later Extended to 80 minutes.
- #16: Students might think the V means Video in DVD. Have them research why it refers to Versatile and not Video in current uses.
- #17: The DVD-R (Recordable) format is designed to fill much the same role with DVDs as CD-R does with CDs. DVD-R can be used to burn large data disks, and it is currently the most reliable media for burning DVD video to discs that can play back in set-top DVD players. The DVD-RW (ReWritable) format was designed for sequential recording to support recording of streaming media, including for consumer video recorders. DVD-RW discs should be reusable over 1000 times, with an estimated lifetime of 30 to 50 years. It is somewhat less compatible than DVD-R with existing DVD players.
- #18: Note: Prior to Jan. 08, there were two formats competing to become the standard. Blu-ray was adopted as the format standard for all high definition video discs. Toshiba's HD-DVD used on the X-Box lost the high definition storage battle.
- #20: While costs and sizes of solid state storage are in flux, when compared with magnetic disk storage they continue to be more expensive and have a limited capacity. Future trends however, suggest that Flash storage drives will be embedded in the computer system. Have students research why this storage was called "flash" storage. All data is re-written on the drive at once in a "flash."
- #21: Class discussion on the future of digital data is based on historic changes to hardware and software requirements to access the data. What measures are being taken to effectively store data in formats we can access 20 - 50 years from now? Consider the data on all the floppy disks created in software that no longer exists as a thought provoking issue on future of our "life" and "historic" data.
- #23: Discuss why there are so many pointing device options. Why are they popular on laptop computers? The Wii remote is not developed in the textbook, but students will recognize it as a pointing device for the popular game.
- #25: Use scanner software to demonstrate the settings every scanner application has to capture an image with set spatial and color resolutions. Review the spatial resolution for monitor display is between 72 - 96, for laser printing use 300 dpi. Color resolution is controlled by bit depth: 2 bit color = black and white, 8 bit grayscale, 24 bit color are common settings.
- #27: Students could research digital cameras and discuss the features of each. Special discussion around digital cameras with SLR, special lens additions, and mega-pixel ratings could be part of the review. Recommend a camera that a developer might use to take nature pictures of eagles. Video at How Stuff Works on buying a digital camera : http://electronics.howstuffworks.com/digital-camera.htm
- #34: Have students research why CRTs are losing popularity despite their low cost and better quality image. Monitor size Power consumption Hazardous materials
- #35: Students should explain the difference between Active and Passive matrix. Laptops are built at a fixed number of transistors that determine the resolution. If the settings are altered, the quality of image will be changed.
- #36: Have students visit HowStuffWorks and research how sound cards deliver quality of computer sound. http://computer.howstuffworks.com/sound-card.htm
- #39: Use textbox on Considerations for Selecting a Printer to discuss best options for multimedia development business, a home user, an office user.
- #41: Review with students the meaning of protocol and why common rules or standards would be critical to connect multiple networks together and share data in a efficient manner.
- #42: Students should identify why the WWW is a revolutionary protocol. Consider the cross-platform compatibility for content and wide range of multimedia as part of the discussion. http or Hypertext Transfer Protocol Html is the hypertext markup language that codes the web pages. Review the address structure of a URL and how they differ for internal files and external files.
- #43: Have students comment on benefits of having the processing of data done on a local desktop computer and the communication bandwidth service the transmission of data. Where are the efficiencies in this model? Ethernet is most common LAN technology. Software protocols are available on all PC's and widely supported by Internet protocols. Have students research and explain the distinction between wifi and bluetooth, where they are commonly used, and the new standards for wifi transmission. http://www.awirelesslife.com/wireless.html offers a short clear overview and includes wimax technology.