DVD/CD Drives FAQ for any models

Glossary

 

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

It 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.
 

Hybrid

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 block does not occur and therefore this method is very suitable for pre-mastering and creating music CDs.
 

Track At Once

This method writes data one track at a time, and therefore data can be added. Because data link block 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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