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Technical Notes
CD-R/RW drives are equipped with a buffer memory, which temporarily stores data
that is being transferred. When the buffer memory becomes empty due to a delay of
data transfer for any reason, a writing error happens. Such condition is defined as
buffer underrun, and such an error is defined as a buffer underrun error.
Buffer Underrun Protection is featured in the CRW-F1SX drive.
When buffer underrun almost happens, Buffer Underrun Protection temporarily
suspends the writing process. Writing resumes when enough data has accumulated
in the buffer memory. Buffer Underrun Protection in the CRW-F1SX drive is
extremely accurate, resulting in seamless recording before and after suspension.
Test writing
Test writing is a function to check for the possible occurrence of buffer underrun in your
computer environment. When Buffer Underrun Protection of the CD writing software is
activated, the test writing function cannot be operated. Buffer Underrun Protection
should be deactivated to operate the test writing function.
Disc-at-Once (DAO)
This method is used to write all data onto a disc in one operation. It writes multiple
pieces of data without placing a space between data, starting with the innermost
track of the disc. Once data is written by this method, no data can be added to the
same disc even if there is free space available on the disc. This method is useful for
making a backup copy of an entire disc.
Track-at-Once (TAO)
This method is used to write data on a disc on a track-by-track basis. A track can be
defined as the smallest unit of area that contains an ordinary program, image file,
text file, etc. This method enables you to add data to the same disc, one track of data
at a time, as long as there is free space available on the disc. A disc that contains data
written in several sessions is defined as a multi-session disc. An area that records
data and management information (Lead-in/Lead-out) is defined as a session. Lead-
in and Lead-out are signals written for stating the starting and ending points of one
session.
Ordinary audio CD players can only play back single-session discs or the first session on
a multi-session disc. Do not record audio data on the second and subsequent sessions.
Buffer Underrun Protection Function
Writing Methods
Note
