Tomorrow s Technology and You 8 th Edition Slide 1 Tomorrow s Technology and You 8/e Hardware Basics: Peripherals Slide 2 Objectives List several examples of input devices and explain how they can make it easier to get different types of information into the computer. List several examples of output devices and the explain how they make computers more useful. Explain why a typical computer has different types of storage devices. Diagram how the components of a computer system fit together. Slide 3 1
Keyboard The most familiar input device Used to enter letters, numbers and special characters Slide 4 Standard keyboard Ergonomic keyboards To address possible medical problems Wireless keyboard Folding keyboards Used with palm-sized computers One-handed keyboards Keyboards printed on membranes Slide 5 Pointing Devices Mouse Touchpad Pointing stick Trackball Joystick Graphics tablet Touch screen Stylus Slide 6 2
Reading Tools Read marks representing codes specifically designed for computer input Slide 7 Optical-mark readers Magnetic-ink character readers Bar-code readers Pen scanners Tablet PC Smart whiteboard Radio Frequency Identification Readers (RFID) Slide 8 Digitizing the Real World Scanners capture and digitize printed images. Flatbed Slide Drum Sheet-fed Slide 9 3
Digital camera Snapshots captured as digital images Digital images stored as bit patterns on disks or other digital storage media Slide 10 Video digitizer Capture input from a: Video camera Video cassette recorder or television Convert it to a digital signal Stored in memory and displayed on computer screens Videoconferencing People in diverse locations can see and hear each other Used to conduct long-distance meetings Video images transmitted through networks Slide 11 Audio digitizers Digitize sounds from Microphones Other input devices Digital signals can be Stored Further processed with specialized software A digital signal processing chip compresses the stream of bits before it is transmitted to the CPU. Slide 12 4
Speech recognition software Converts voice data into words that can be edited and printed Slide 13 Sensors Designed to monitor physical conditions Temperature, humidity, pressure Provide data used in: Robotics Environmental climate control Weather forecasting Medical monitoring Biofeedback Scientific research Slide 14 Screen Output A monitor or video display terminal (VDT) displays characters, graphics, photographic images, animation and video. Video adapter connects the monitor to the computer VRAM or video memory a special portion of RAM to hold video images The more video memory, the more picture detail is displayed. Slide 15 5
Monitor size: Measured as a diagonal line across the screen Resolution: The number of pixels displayed on the screen Pixels (or picture elements): tiny dots that compose a picture The higher the resolution, the closer together the dots. Image quality is affected by resolution and color depth (or bit depth). Color depth refers to the number of different colors a monitor displays at one time. Slide 16 Color depth 1-bit depth 4-bit depth 8-bit depth 16-bit depth Slide 17 Monitor classes CRTs (cathode-ray tubes) LCDs (liquid crystal displays) Overhead projection panels Video projectors Portable computers Slide 18 6
Paper Output Printers produce paper output or hard copy. Two basic groups of printers: Impact printers Line printers Dot-matrix printers Slide 19 Non-impact printers Laser printers Laser beam reflected off a rotating drum to create patterns of electrical charges Faster and more expensive than dot matrix printer High-resolution output Inkjet printers Sprays ink onto paper to produce printed text and graphic images Prints fewer pages/minute than laser printer High-quality color; costs less than laser printer Slide 20 Multifunction printer or MFP combines a scanner, printer and a fax modem. A plotter can produce large, finely scaled engineering blueprints and maps. Slide 21 7
Fax Machines and Fax Modems Facsimile (fax) machine Sending: scans each page as an image converts the image into a series of electronic pulses sends those signals over phone lines to another fax Receiving: uses the signals to reconstruct the image prints black-and-white facsimiles or copies of the originals Fax modem Connect from PC to fax machine via modem and phone line Slide 22 Output You Can Hear Sound card Enables the PC to: Accept microphone input Play music and other sound through speakers or headphones Process sound in a variety of ways Synthesizers Used to produce music, noise Slide 23 Controlling Other Machines Output devices take bit patterns and turn them into non-digital movements. Robot arms Telephone switchboards Transportation devices Automated factory equipment Spacecraft Force feedback joystick Slide 24 8
Rules of Thumb: Ergonomics and Health Choose equipment that s ergonomically designed. Create a healthy workspace. Build flexibility into your work environment. Rest your eyes. Stretch to loosen tight muscles. Listen to your body. Seek help when you need it. Slide 25 Storage Devices: Input Meets Output Magnetic Tape Can store large amounts of information in a small space at a relatively low cost Limitation: sequential data access Used mainly for backup purposes Slide 26 Storage Devices: Input Meets Output Magnetic Disks Random data access Floppy disks Provide inexpensive, portable storage Hard disks Non-removable, rigid disks that spin continuously and rapidly Provide much faster access than a floppy disk Removable media (Zip & Jaz disks) Provides high-capacity portable storage Slide 27 9
Storage Devices: Input Meets Output Optical Disks Use laser beams to read and write bits of information on the disk surface Not as fast as magnetic hard disks Massive storage capacity Very reliable Slide 28 Storage Devices: Input Meets Output CD-ROM Optical drives that read CD-ROMs CD-R WORM media (write-once, read many) CD-RW Can read CD-ROMs and write, erase and rewrite data onto CD-R & CD-RW disks Slide 29 Storage Devices: Input Meets Output DVD (Digital Versatile Disks) Store and distribute all kinds of data Hold between 3.8 and 17 gigabytes of information DVD-ROM drives Can play DVD movies, read DVD data disks Read standard CD-ROMs, and play audio CDs Read-only: can t record data, music, or movies DVD-RAM drives Can read, erase, and write data (but not DVD video) on multi-gigabyte DVD-R (but not CD-R or CD-RW) media Slide 30 10
Storage Devices: Input Meets Output Solid-State Storage Devices Flash memory is an erasable memory chip: Sizes range from 16 MB to 1 GB Compact alternative to disk storage Contains no moving parts Designed for specific applications such as storing pictures in digital cameras Likely to replace disk and tape storage Slide 31 Computer Systems: The Sum of Its Parts Personal Computer Design Classes Tower systems Tall, narrow boxes, generally have more expansion slots and bays than other designs Flat desktop systems Designed to sit under the monitor like a platform All-in-one systems (like the imac) Combine monitor and system unit into a single housing Slide 32 Computer Systems: The Sum of Its Parts Laptop computers Include all the essential components, including keyboard and pointing device, in one compact box Slide 33 11
Computer Systems: The Sum of Its Parts Ports and Slots Revisited The system or motherboard includes several standard ports: Serial Port for attaching devices that send/receive messages one bit at a time (modems) Parallel Port for attaching devices that send/receive bits in groups (printers) Keyboard/Mouse Port for attaching a keyboard and a mouse Slide 34 Computer Systems: The Sum of Its Parts Other ports are typically included on expansion boards rather than the system board: A video port is used to plug a color monitor into the video board. Microphones, speakers, headphones, MIDI ports are used to attach sound equipment. An SCSI port allows several peripherals to be strung together and attached to a single port. A LAN port uses faster connections to a localarea network (LAN). Slide 35 Computer Systems: The Sum of Its Parts Expansion Made Easy With the PC open architecture and the introduction of new interfaces, you can hot swap devices. USB (Universal Serial Bus) transmits a hundred times faster than a PC serial port Firewire (IEEE 1394) can move data between devices at 400 or more megabits per second. The high speed makes it ideal for data-intensive work, like digital video. FireWire 800, which offers 800 Mbps transfer speeds, was recently introduced on high-end Macintosh systems. Slide 36 12
Computer Systems: The Sum of Its Parts Putting It All Together A typical computer system might have several different input, output, and storage peripherals the key is compatibility. Networks blur the boundaries between computers. Networked computers may have access to all the peripherals on a system. The computer is, in effect, just a tiny part of a global system of interconnected networks. Slide 37 Inventing the Future: Tomorrow s Peripherals Tomorrow s Storage Smaller disks that hold more A single electron memory chip the size of a thumbnail that can store all of the sounds and images of a full-length feature film Tomorrow s Output Flat-panel screens replacing desktop CRTs Retinal displays that work without a screen Slide 38 Inventing the Future: Tomorrow s Peripherals Tomorrow s Input: Sensors More sophisticated devices will serve as eyes, ears, and other types of sense organs for computer networks. Slide 39 13
Lesson Summary Peripherals allow computer to communicate with the outside world and store information for later use information. The most common input devices today are the keyboard and the mouse. A variety of other input devices can be connected to the computer. Output devices perform the opposite function: They accept strings of bits from the computer and transform them into a form that is useful or meaningful outside the computer. Slide 40 Lesson Summary (continued) Storage devices are capable of two-way communication with the computer. Because of their high-speed random access capability, magnetic disks are the most common forms of storage on modern computers. Network connections make it possible for computers to communicate with one another directly. Slide 41 14