File system-related glossary
When creating a CD, you need to select a file system suitable
for the environment (Windows, Mac, UNIX) where the CD will be played.
Main file systems are ISO9660, Joliet, Romeo, HFS, and Hybrid. Each
file system has different restrictions on the length of file name
and location.
 ISO9660
Used for playing CDs in different OSs such as Windows
and Mac. ISO9660 file system limits the file name to 8 characters
with file extension up to 3 characters. Only alphabet, number
(0-9) and underscore (_) can be used in the file name (8.3
format).
Joliet
TIt is a Microsoft's proprietary file system where a long
file name of up to 64 characters can be used. Because this
file system overlaps with the ISO9660 file system, OSs which
do not support Joliet can still read the files using the 8.3
format.
ROMEO
This is also a Microsoft's proprietary file system where a
long file name of up to 128 characters can be used. This file
format is not compatible with ISO9660 and is limited to Windows95/NT
only.
HFS
(Hierarchical File System)
This is a complete implementation of the MacOS's file
system on CD-ROM. Its use is limited to the MacOS environment
only.
Business
Card-sized CD-R
Where two file systems exist on the same
CD-ROM.
Write-related glossary
For writing data to a CD, two methods
are available: the Disc At Once method which
writes all of the data at once to the disc;
and the Incremental Write method which writes
data in units of smaller chunks. According
to the unit size, the Incremental Write method
can further be broken down into three types:
Session At Once, Track At Once, and Packet
Write.
JustLink
Buffer underrun errors that would occur when data transfer
falls behind writing operation has been inevitable for CD-R/RW
drives. Just Link, which we at Ricoh developed on our own,
is a new technology that predicts possible occurrences of buffer
underrun errors in advance and automatically avoids them. The
MP5120A is the industry's drive that features Just Link. With
this technology, the MP5120A ensures stable writing operation
even under circumstances where buffer underrun errors tend
to occur with conventional drives.
Disc
At Once
This method writes the whole data at once, not incrementally.
As a result, data link mainclass does not occur and therefore this
method is very suitable for pre-mastering and creating music
CDs.
Track
At Once
RThis method writes data one track at a time,
and therefore data can be added. Because
data link mainclass is resulted, this method
is not suitable for creating music CDs with
no no-sound portion (such as live recording).
This is the main-stream write method used
by mastering-type writing software.
Packet
Write
This method writes data in smaller chunks than session and
track, It writes data in packets (64 KB for UDF2.0) Because
data can be deleted and written in units of files, this method
enables you to use CD-R/CD-RW discs like floppy disks. In terms
of packet writing software, two types are available. One type
uses a proprietary format while the other type is based on
the UDF standard which is compatible with DVD.
UDF
(Universal Disc Format)
It is a worldwide standard in packet writing
method. It's file format was first adopted
on DVD-ROM and later extended to CD. As the
laser disc's standard format it replaces
ISO9660 (which imposes restrictions on file
name, etc.) and is expected to become the
main recording format of CDs.
Multi-session
In this method, data on a CD is formed by
a session consisting of [Lead-In/Program
Area/Lead-Out]. When data is added to the
CD-R/CD-RW disc using Track At Once method,
the new session is added after the previous
session. A CD with data added in this way
is called a multi-session CD. Because music
CD players can only play the first session,
when creating CD-DA, use Single Session to
perform the write operation.
Session
Close
This is a process to enclose data area. The
Lead-In area precedes the data area which
is then followed by the Lead-Out area. If
this process is not performed, the created
disc cannot be read from a CD-ROM drive.
Finalize
When a disc is created using the Multi-session
method, after data is written onto the disc,
prohibition to add is specified and then
Session Close is performed. Then, when the
Finalize process is executed, no more addition
onto the disc is allowed.
CD format-related glossary
CD-DA(Compact
Disc-Digital Audio)
In other words they are music CDs. The discs contain
only music data and data is written using the Single
Session method.
Video
CD
CD-ROM storing mainly MPEG-compressed video,
together with still picture and sound.
CD-ROM
XA
CD-ROM storing both music/video and data.
Mixed
Mode CD
Both music and data are stored in the same session.
Because they may cause music CD players to malfunction,
they are not commonly used now.
CD-EXTRA
It is a format which improves the problem
of Mixed Mode CD. In this format music and
data are stored separately in two sessions.
PhotoCD
Refers to a CD format devised by Eastman
Kodak to record digitized photos, as well
as the whole system.
Other glossary
DVD+RW
DVD+(plus)RW refers to a specification for 4.7-GB rewritable
DVDs. The revolutionary features of DVD+RW are complete compatibility
with CD-R/RW from which it was developed further, and its usability
as a PC peripheral device.
It has achieved high compatibility with existing
DVD-ROM drives and DVD-Video players, and
it has gained ease of use in operation from
PCs thanks to some improvement including
reduction of formatting time and as much
as 2.4 times of speed (about 20x when converted
for CD) made possible.
Multi-read
CD-ROM drive
A CD-ROM or DVD-ROM drive which can read
CD-RW discs formatted by UDF or ISO9660.
The drive comes added with an AGC (Auto Gain
Control) device and modified firmware for
reading CD-RW discs with low reflection rate.
High
Speed CD-RW Media
The high-speed CD-RW
media is a type of media that conforms to a new CD-RW media standard
instituted for high-speed (4x to 10x) recording.
It can be used only with those drives bearing
the "High Speed CD-RW" logo.
Ultra
DMA33
A method in which data is transferred on
both the rising edge and falling edge of
the chip set's operating clock, thus achieving
a maximum data transfer rate of 33 MB/s,
double the conventional rate. In order that
this protocol can operate, the connected
device (drive) and the chip set itself need
to support this protocol, and a dedicated
driver file is required.
If you want to use a new chip set, you must
obtain a driver for it separately from those
chip set drivers that comes with the operating
system as standard. Since the increased transfer
rate may cause a noise problem, you must
pay attention to the length of the flat cable
used, and the noise generated by the PC system
itself.
Multiword
DMA
A transfer method in which a chip set (DMA
controller) directly performs data transfer
in place of the CPU. In Multiword DMA Mode-2,
data can be transferred at the rate of 16.6
MB/s, which is equivalent to the PIO Mode-4,
lightening the CPU load. This protocol requires
support by the chip set and its dedicated
driver file.
Although Windows 98 and Windows Me includes
some chip set drivers as standard, you may
need to obtain a driver separately when you
use a new chip set.
Programmed
I/O (PIO)
A transfer method in which the CPU directly
performs data transfer. In Mode-4, which
achieves the maximum rate, data transfer
at the rate of 16.6 MB/s is possible, but
that greatly burdens the CPU load in Windows
OSes that perform multitask operation.
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