Yamaha Comprehensive Guide to Partial CAV Constant Angular Velocity for the CRW3200

Partial CAV (Constant Angular Velocity)

The CLV (Constant Linear Velocity) method is generally used to write data on a CD-R disc. In writing using the CLV method, the disc rotation speed is adjusted to keep the data writing speed (data transfer rate) constant on all parts of the disc.

In contrast, the CAV (Constant Angular Velocity) method exercises control so as to keep the disc rotation speed constant. Since the CAV method makes it possible to substantially increase the maximum data transfer rate without straining of the drive, it is adopted today for most CD-ROM drives.

CD formats define the constant linear density of written data so that the amount of written data per disc rotation will increase as the writing point moves from the inner track to the outer track.

With the CAV method, therefore, data is transferred at a higher rate when it is written on the outer tracks of the disc. To achieve 24X-speed writing, the CRW3200E drive employs the Partial CAV method, which is a combination of the CAV method for inner tracks and the CLV method for outer tracks.

The Partial CAV method controls the disc rotation speed so that the CRW3200E drive starts writing at 18X speed on inner tracks, increasing the speed to 24X as the read/write head moves outward and holds the speed at 24X on outer tracks.

Tip

The CRW3200E drive supports 8cm discs.

Note

Use only circular discs. Do not use any irregular shaped discs such as heart-shaped or star-shaped discs to avoid the risk of malfunction.

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