EET Advance Digital Chapter 12 CD - CDR - DVD

Compact Disk Technology Information stored on a reflective surface, read with a laser beam. 74 minutes or 640 Mb of data storage –Current 80 min/700 Mb CD-ROM is a read only version. –Data is recorded at manufacture using a printing-style operation

Transfer rates have been increasing –See Table for speeds A more important measure is access time. –Massive (relatively) mechanism means slow response to move the read head into position to read information.

Speed comparison CD Drive SpeedData Rate Kbps 1x150 4x600 10x1,500 12x1,800 24x3,600 32x4,800 40x6,000 48x7, x15,000

Speed comparison Drive SpeedAccess Time (ms) 1x400 2x300 3x200 4x150 6x150 8x – 12 x100 16x – 24x90 32x – 52x or greater85-75 or less

CD-Rom Drive

CD-R - Recordable media Same storage capacity, but media uses an organic dye –Some makers now featuring 700Mb (80min) The dye reflectivity is changed with a low power laser. –Storage is a WORM variety

ISO 9660

CD-R Media Color Reflective layer/Die Layer –Gold-gold – Phthalocyanine dye Less tolerance for power variations –Gold-green – Cyanine dye More forgiving 10 yr life span –Silver-blue – Azo dye Similar to green, but rated to 100 years.

CD-RW - Re-writable CD Uses a phase-change technology Same storage capacity as CD active layer of CD-RW is Ag-In-Sb-Te –Silver - indium - antimony - tellurium –polycrystalline structure is reflective –High power laser heats to degrees

–This solidifies in a non-reflective state –To erase, a lower power laser heats to 200 degrees, which solidifies in the original reflective state.

CD-ROM Disc & Drive Formats Red Book –Digital Audio CDs (CDDA) Yellow Book –Computer CDs –Mode 1: ISO 9660 –Level 1: PC, Apple, UNIX, DVI –Level 2: CDTV

CD-ROM Disc & Drive Formats White Book –Video CD –MPEG-1, MPEG-2 Orange Book –Writeable CDs – CDR

Green Book –Combination of Red and Yellow Books –CD-I CD + (Enhanced CD) –Combines Music and computer Data on 1 CD

Data Standard: ISO 9660 High Sierra Format CD-CA (digital Audio) CD-ROM XA – extended architecture –Multi-session CDs

DVD Digital Versatile Disk –initial capacity 4.7 G minutes of video with three audio and four sub-title channels. –8.5 G dual layer disks - use a semi reflective top layer. –double sided 9.4G single layer 17G double layer

Additional capacity from –smaller pit length –reduced track pitch –larger data area on disk –More efficient modulation –More efficient error correction code –less sector overhead

Short wave-length laser reads fast transfer rate - ~ 9x by CD-Rom standards interface - standard IDE/ATA or SCSI

Standard DVD Formats FormatSizeS/layersCapacity DVD-5120mmS/s4.7G DVD-9120mmS/d8.5G DVD-10120mmD/s9.4G DVD-14120mmD/d13.24G DVD-18120mmD/d17G DVD-180mmS/s1.4G DVD-280mmS/d2.7G DVDR-1120mmS/s2.58G DVDR-2120mmD/s9.4G

Recordable DVD –Two standards –DVD-R WORM type –DVD-RAM re-writable like CD-RW

Recordable DVD Standards DVD-RAM – 2.6 G/side –Not compatible w/ DVD ROM $25/disk DVD-R – 4.7G (1999 version) –Almost all can read this format $40/disk DVD-RW – 4.7G –Almost all can read this format $40/disk DVD+RW – 2.8G/side –A few current from Sony or Phillips $30/disk

DVD Ram encoding

DVD-Ram

DVD-R Wobbled Groove

DVD-R

MultiRead & MultiRead2 MediaMultiReadMultiRead2 CD-DA (audio)XX CD-ROMXX CD-RXX CD-RWXX DVD-ROM-X DVD-Video-X DVD-Audio-X DVD-Ram-X

References ocs/dvdramwhitepaper.shtmlhttp:// ocs/dvdramwhitepaper.shtml Mueller, S., Upgrading and Maintaining PC’s 12e, 2000, Que Corp.