Chapter 11 Multimedia Devices and Mass Storage. You Will Learn… About multimedia devices such as sound cards, digital cameras, and MP3 players About.
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You Will Learn…
About multimedia devices such as sound cards, digital cameras, and MP3 players
About optical storage technologies such as CD and DVD
About tape drives and removable drives How certain hardware devices are used for backup
and fault tolerance How to troubleshoot multimedia and mass storage
devices
Multimedia on a PC
Goal• To create or reproduce lifelike representations of
sight and sound
Challenge• Data storage is digital
• Sights and sounds are analog
CPU Technologies for Multimedia
MMX, SSE, and 3DNow!• Improve speed of processing graphics, video, and
sound
• Use improved methods of handling high-volume repetition during I/O operations
Software must be written to use the specific capabilities
Sound Cards
Record sound, save it to a file on hard drive, play it back
Have ports for external stereo speakers and microphone input
May be SoundBlaster compatible
Stages of Computerized Sound
Digitize or input the sound (analog to digital)• Includes sampling
• Data is measured at a series of representative points• Sampling rate = cycles per second, or hertz (Hz)
Store digital data in a compressed data file Reproduce or synthesize the sound (digital to
analog)
Installing a Sound Card
Physically install the card in an empty PCI slot on the motherboard
Install the sound card driver Install the sound application software
Digital Cameras
Use light sensors to detect light and convert it to a digital signal stored in an image file using JPEG format
Use TWAIN format for transferring images Camera’s image-editing software (or another
program) can be used to view, touch up, and print the picture
MP3 Players
Store and play MP3 files downloaded from a PC, using internal memory and flash storage devices
Compression Methods Used with MP3 Players
MPEG (Moving Pictures Experts Group) standard• Tracks movement from one frame to the next and
stores only what changes
• Cuts out or drastically reduces sound that is not normally heard by the human ear
MPEG Standards
MPEG-1• Used in business and home applications to compress
images
MPEG-2• Used to compress video films on DVD-ROM
MPEG-3• Used for audio compression
MPEG-4• Used for video transmissions over the Internet
How MP3 Players Work
Play MP3 files downloaded from a PC, using internal memory and flash storage devices (eg, SmartMedia, CompactFlash, or Memory Stick)
Features to Look for on a Video Capture Card
IEEE 1394 (FireWire) port to interface with a digital camcorder
Data transfer rates, which affect price Capture resolution and color-depth capabilities Ability to transfer data back to digital camcorder or
VCR Stereo audio jacks Video-editing software bundled with the card
Optical Storage Technology
Patterns of tiny pits on disc surface represent bits, which are read by a laser beam
Major optical storage technologies• CD-ROM drives
• Use CDFS (Compact Disc File System) or UDF (Universal Disk Format)
• DVD drives• Use only UDF
CD-ROM
Data physically embedded into disc surface
Surface laid out as one continuous spiral of sectors of equal length that hold equal amounts of data in pits and lands
CD-ROM
Read-only Slower to access than hard drives Used to distribute software and sound files Combines constant linear velocity (CLV) and
constant angular velocity (CAV) Look for multisession feature
CD-ROMs
Caring for CD-ROM drives and discs• Use precautions when handling
CD-ROM drive interface with motherboard• IDE interface (most common)
• SCSI interface with SCSI host adapter
• Proprietary expansion card that works only with CD-ROMs from a particular manufacturer
• Proprietary connection on sound card
• Portable drive; plug into external port on PC
Accessing CD-ROM Drive When Booting from a Floppy Disk
Windows rescue disk needs to include tools to access CD-ROM drive in the event of hard drive failure• There will be no access to 32-bit Windows CD-ROM
drivers on the hard drive
Files required to access a CD-ROM drive while in real mode:• 16-bit device driver provided by manufacturer of CD-ROM
drive; loaded from Config.sys• 16-bit real-mode OS interface to the driver, Mscdex.exe;
loaded from Autoexec.bat
CD-R (CD-Recordable) Drives and Discs
Enables “burning” your own CDs Used for distributing software or large amounts of
data Cannot edit or overwrite Allow for a lot of data storage on a relatively
inexpensive medium Bottom of disk is tinted (eg, blue, black); CDs are
silver Can be read by all CD-ROM drives
CD-RW (CD-Rewritable) Drives and Discs
Allows overwriting old data with new data Cannot always be read by older drives More expensive than CD-R discs
DVD (Digital Video Disc)
Storage capacity• 8.5 GB (one side)• 17 GB (both sides)
Uses Universal Disk Format (UDF) file system Uses shorter wavelength laser than CD; a second
opaque layer also holds data Uses MPEG-2 video compression; requires MPEG-2
controller to decode compressed data Audio is stored in Dolby AC-3 compression
Tape Drives
Advantages• Inexpensive and
convenient
• Large capacity
• Several types and formats
Disadvantage• Sequential access
How a Tape Drive Interfaces with a Computer
External• Parallel port with optional pass-through to the
printer
Internal• IDE ATAPI interface (most popular)
External or internal• SCSI bus• Proprietary controller card or floppy drive interface
Tapes Used by a Tape Drive
Two kinds• Full-sized data cartridges• Minicartridges (more popular)
Standards• Quarter-Inch Committee (QIC) or quarter-inch
cartridge standards (not used much today)• Travan by 3M (popular, improved group of
standards)
Removable Drives
Can be internal or external Advantages
• Increase overall storage capacity of a system• Make it easy to move large files from one
computer to another• Serve as a convenient medium for making backups
of hard drive data• Make it easy to secure important files
Considerations When Purchasing a Removable Drive
Drop height Half-life of the disk Plug and Play compliance
Types of Removable Drives
Iomega 3½-inch Zip drive• Stores 100 MB or 250 MB of data• Drop height of 8 feet
SuperDisk by Imation or Maxell• Stores 120 MB or 240 MB, respectively• Backward compatibility with regular floppy disks
Iomega Jaz drive• Stores 1 GB or 2 GB of data• Drop height of 3 feet
Installing a Removable Drive
Internal removable drive• Similar to installing a hard drive
External removable drive• Different process
Troubleshooting Guidelines
Do not touch chips on circuit boards or disk surfaces where data is stored
Do not stack components on top of one another Do not subject them to magnetic fields or ESD
Problems with CD-ROM or DVD Installations
Computer does not recognize the drive (no drive D listed in Windows 9x Explorer)• Check data cable and power cord connections• For an IDE drive
• Is correct master/slave jumper set?• Is IDE connection on motherboard disabled in CMOS setup?
• For SCSI, are proper IDs set? Most current drivers installed?
• Another device using same port settings?• Suspect a boot virus
Troubleshooting Sound Problems
Problem with sound card itself Result of system settings Bad connections
Troubleshooting Tape Drives
A minicartridge does not work Data transfer is slow Drive does not work after installation Drive fails intermittently or gives errors
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