Yamaha CRW2200IX Series, Руководство пользователя

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Before Use
7
About the Orange Book
The Orange Book standard defines how all recordable discs (including CD-R and CD-RW) are
written. Part 2 of the Orange Book standard relates to CD-R discs, and Part 3 to CD-RW discs.
The standard was named after the color of the book’s cover.
About CD-ROMs
A CD-ROM disc is a compact disc containing high-density read-only data. It has
many applications, including the playback of music and video, the archiving of
data, as well as on-line documentation. The following are descriptions of each
CD-ROM format:
CD-DA: Up to 79 minutes of stereo audio is written in 16-bit resolution at a
sampling rate of 44.1 kHz for a 79 minute disc.
Data CD: Up to 700 megabytes of computer data is stored in standard ISO9660
format for a 700 MB disc.
Video CD: These hold movies in which video and audio data has been
compressed using MPEG-1 technology.
About Partial CAV (Constant Angular Velocity)
Writing to a CD-R disc is normally done using the CLV (Constant Linear
Velocity) method. In this method, the disc rotation speed is adjusted so as to
keep a constant data transfer rate at any portion of the disc. In other words, the
disc rotation speed will vary in CLV writing.
In contrast, the CAV (Constant Angular Velocity) method uses a constant disc
rotation speed for all portions of the disc so that the data transfer rate will vary.
Because the CAV method has the advantage of largely increasing the data
transfer rate with a minimum load to the drive’s mechanism (compared to CLV’s
rotation speed adjustment), many current CD-ROM drives use the CAV method.
CD formats define the constant linear density of written data (data should be
written onto the disc at a constant pitch) so that the amount of recorded data per
disc rotation will increase as the writing point moves from the inner to the outer.
In other words, in CAV writing, the outer portion has an increased data transfer
rate.
The CRW2200IX drive uses the CAV method in the inner portions as well as
the CLV method in the outer portions (Partial CAV) in order to enable up to
20X-speed writing. The drive will control the disc rotation speed to start writing
at 12X speed in the inner portions, gradually accelerating up to 20X speed and
maintaining 20X speed in the outer portions.