GB2440687A

GB2440687A - Setting an optical drive write strategy

Info

Publication number: GB2440687A
Application number: GB0719830A
Authority: GB
Inventors: Munif Halloush Farhan; Christiaan Steenbergen; Steve Kutz
Original assignee: Dell Products LP
Current assignee: Dell Products LP
Priority date: 2003-10-18
Filing date: 2004-09-30
Publication date: 2008-02-06
Anticipated expiration: 2024-09-30
Also published as: GB2440687B; GB0719830D0

Abstract

A method of writing information to an optical media comprises reading an identification code from the medium 20; selecting a write strategy associated with the code if the code is assigned to an existing medium 22, selecting a general write strategy if the code is pre-assigned to a planned optical medium which is not released at the time of manufacture of the drive; and writing to the medium using the selected write strategy. The pre-assigned identification code may be pre-assigned to a manufacturer of media, and may comprise similarities with one or more existing optical media of the manufacturer. The write strategy may comprise a write speed and the medium may be written at the lesser of the write speed and the maximum speed of the drive. Should the media identity code not be associated with either a write strategy or a general write strategy the information may be written using a generic write strategy, 28. The optical medium may be one of CD-R, CD-RW or DVD and the medium identity code may be an ATIP start code.

Description

MTROD AND SYSTEM PORSETrI&G OPTICAL DRIVE-WRiTE-SPEED BACKGROUNI) OF

THE INVENTION

Field of the Invention

The present invention relates in general to the field of information handling system optical drive operation, and more particularly to a method and system for setting optical drive write speed for wilting information to optical media.

Description of the Related Art

A the value and use of inJrmafiou continues to inciasc, individuals and businesses seek additional ways to process and store infbrmation. One option available to users is infbrmation handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling nccds and requirecnts vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much infonnation is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated.

The variations in infonnat ion handling systems allow for Information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservation, enterprise data storage, or global communications. In addition, inlkrination handling systems may include a variety of hardware and software components that may be configured to process, store, and conanuujoate infonnation and may include one or more computer systems, data storagesystems,and-nePvorking-stcms.

As information handling systems have proliferated, so has the amount of infonnation handled and stored by information bandling system users. One increasingly used option for storing these greater amounts of information is optical media. Optical disc drives write information to optical media with lasers that illuminate an optical medium to selectively alter the reflective qualities of the optical medium, and read the information by illuminating the optical medium with the laser at a lower power to measure the reflection from the optical medium. Typically, each optical drive writes to different types of optical media with write strategies developed by the optical drive manufacturer. As optical media manufacturers produce improved optical media, such as optical media that will accept information at eater optical drive write speeds, optical drive manufacturers update the firmware of the optical drives to have write strategies developed for the improved optical media. For instance, a CD- RW optical drive reads embedded ATW start codes from CD-R optical discs to uniquely identify the CD-R medium. The optical drive then writes information to the medium using a write strategy associated with the ATIP start code that the optical drive has In a table in firmware. A standards body known as the Orange Fonun assigns codes to CD-R and Ct)-RW optical media manufacturers each time a new optical medium is released so that optical drive nianufiicturers can develop optimal write speeds and strategies for use with the medium and store the developed write speed and strategy in finnware. Other optical media, such as DVI) media, have or may have similar implementations of such identification codes, either through assignment by a standards body or selladministered.

One difficulty that arises with the use of enibedded codes on optical media to identify the media for optical drives is that an optical drive may read an embedded code from an inserted optical medium that the optical drive does not recognize. If the embedded identification code of an optical medium is not found in an optical drive's firmware, the optical drive typically reverts to a generic write strategy and write speed. Generally, optical drives slow the write speed for the genetic write strategy to a value at which an acceptable quality write of information results regardless of the optical medium. However, the write speeds of optical drives and optical media tend ) to increase over time so that the U86 of a slow write speed with an wireeognized -embedded code generally is an overly conservative approach. For instance, CD-R and CD-RW optioal drive manufacturers typically load a culTent ATIP stait tablo Lu firmware of optical drives at manufacture but do not typically update the firmware after manufacture. Thus, an optical drive Installed in an information handling system may fail to recognize ATIP stait codes of optical media released a.fter manufacture of the optical drive, resulting in writes at slower speeds with generic write strategies even though newly developed optical media are typically designed to write at higher speeds. One solution is to compare an unrecognized ATIP stall code with known codes, such as the last two digits of an ATIP start code. The write strategy for the closest known code is used to write infonnation to the medium having the unknown code. Rowever, use of write strategies of numerically close codes is unreliable and often little more than a guess that a proximately numbered optical media has similar write characteristics to an unknown optical media.

SIJMMARY 01? TUE INVENTION Therefore a need has arisen fbr a method and system which identifies optical media sufficiently fbr an optical disc drive to associate a write strategy with the optical media even though the optical media is released after the optical drive.

In accordance with the present invention, ainethod and system are provided which substantially reduce the disadvantages and problems associated with previous methods and systems for writing information from an optical disc drive to an optical mediwn released after the optical disc drive. Optical medium identification codes are preassigned to planned optical media, such as through an assigning standards body or through a parameter set that includes release date, and made available for loading onto optical disc drives. Optical disc drives manufactured before the development of write strategies for the planned optical media associate the preassigned identification codes with general write strategies that are based on design parameters of the planned optical media, such as the most recent precursor of the medium available to the drive manufacturer. Preassigument of identification codes to optical media improves write speed of optical drives that write to optical media released after manufacture of the optical drive since the optical drives since the optical drives default to a slow speed genwri*teifeiso More specifically, a manufacturer loads a manufactured optical disc drive with preassigned optical media identification codes and associates the preassigned identification codes with general write strategies. The general write strategies are developed from manufacturer design parameters so that a planned optical media identified by a preassigned code will have a general write strategy that allows writing at a greater write speed than is allowed by the optical disc drive's more conservative catch-all generic write strategy. For instance, optical medium identification codes are preassigned by optical media manufacturer so that a disc drive may use the write strategies of existing optical media of a manufacturer as a base point for planned optical media of that manufacturer. In one embodiment, the identification code has a common number for a given set of related optical media and ends with a date stamp that identifies the version of the optical media by its release date. A write strategy module of the optical disc drive reads the identification code from an inserted optical medium and detennines if the identification code is associated with an assigned, preassigned or unknown optical medium. If the identification code is assigned or preassigned so that it has an associated write strategy, then that mite strategy is used to write information to the optical medium. If the identification code is unknown, then a catch-all generic write strategy is applied to write the information.

The present invention provides a number of important technical advantages.

One example of an important technical advantage is that an optical disc drive identifies optical media sufficiently to associate a write strategy with the optical media even though the optical media is released after the optical drive. Preassigned optical media identification codes allow development of general write strategies for planned optical media so that optical disc drives released before the development of a write strategy for an optical medium are able to write at greater speeds than otherwise supported by a conservative catch-all generic write strategy. The ability to write at greater speeds to newly released media with existing optical drives reduces the perception by users that the optical drive is malfunctioning and thus increases user satisfaction with reduced service calls and returns of optical drives.

BRIEF DESCRIPTION OF THE DRAWJNGS

The present invention will be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 depicts a block diagram of an information handling system having an optical drive that writes infonnation to optical media based on preassigned identification codes; and Figure 2 depicts a flow diagram of a method for writing infbrmation with preassigned optical media identification codes.

DETAILED DESCRIPTION

An optical disc drive stores Information generated by an information handling system onto an optical medium for which the disc drive lacked a write strategy at its manufacture by recognizing an identification code of the optical medium as a preassigned identification code. Information from the information handling system is written to the optical medium with a general write strategy associated with the preassigned identification code and developed based on design parameters of an optical medium planned at the time of manufacture of the disc drive. For purposes of this application, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classic', process, transmit, receive, retrieve, originate switch, store, display, manifest, detect, record. reproduce, handle, or utilize any form of infbrmation, intelligence, or data for business, scientific.

control, or other purposes. For example, an information handling system may be a peraonal computer, a network storage device, or any other uitabIo device and may vary in size, shape, performance, tbnctlonality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and Infonnation handling system may also include one or more buses operable to transmit communications between the various hardware components.

Referring now to Figure 1, a block diagram depicts an information handling system 10 having an optical disc drive 12 that writes information to an optical medium 14 with a write stegy associated with a preassigned optical medium identification code. rnformation processing components associated with information handling system 10 generate information for storage and communicate the infounation to optical disc drive 12. Optical disc drive 12 prepares to write the infonnation to optical medium 14 by reading an optical medium identification from optical medium 14 with a laser 16. For instance, an ATIP start code issued by the Orange l7oxum for CD-It optical media is read from an inner diameter area. Other types of writable optical media, such as CD+RW, DVD-R. DVD-RW and DVD+RW optical media, may be identified with 9imilar codes embedded in the optical media at manufacture. The read optical medium identification code is compared with codes listed in a write strategy table 18 to determine a write strategy for writing the information to the optical medium.

Write strategy table 18 is stored in memory associated with optical disc drive 12, such as the firmware of optical disc drive 12 or memory of the information processing components that is accessible by flxnrware. Write strategy table 18 is populated at manufacture of optical disc drive 12 with the write strategies developed by the manufacturer for known and tested optical media. For instanc; the optical disc drive manufacturer tests each of the different types of optical media available to determine a write strategy settings for power, speed, and pulse characteristics, like pulse length, duration, delay and shape, that writes information with a desired accuracy on each optical medium. The optical disc drive manufacturer associates a write strategy with each type of optical medium's unique identiflcation code. These write strategies are stored as assigned write strategies since each identification code is assigned to a particular optical medium type of an optical medium manufacturer.

0 Write strategy table ISis also populated at manufacture of optical disc drive 12 with generic and general write strategies for use where an optical medium 14 has an unknown identification code or an identification code for which the optical disc drive manufacturer has not developed an associated write strategy. The generic write strategy writes information at a conservative speed setting in order to allow optical disc drive 12 to write information on virtually any optical medium having an unknown identification code with acceptable quality. Although this conservative generic write strategy ensures accurate writing of infounation on less advanced optical medium designed fbr use at lower writing speeds, its use on newly developed optical media designed tbr use at higher writing speeds needlessly slows the writing of information by optical disc drive 12. For instance, an Information handling system user who puts a new optical medium into a new optical disc drive expects the drive to write at or near its maximum speed. However, if the optical disc drive manufacturer did not have a write strategy for the new optical medium at the manufacture of the optical disc drive, then use of the generic write strategy available for unknown optical media will result in a slow write speed and create a perception of improper performance to the user.

In order to prevent unnecessary reliance on the conservatively slow generic write strategy available for use with unknown optical media, optical medium identification codes are preassigned for planned optical media and stored in write strategy table 18. For instance, each optical media manufacturer is preassigned optical medium identification codes for optical media planned for development by that manufacturer, even if the media manufacturer has not begun any development work. The manufacturer provides optical disc drive manufacturers with design parametci for the planned optical medium, such as planned write speeds or the planned optical medium's relationship to existing optical medium of the nianufcturer. The optical disc drive manufacturer is then able to develop general write strategies for the planned optical media and associate the general write strategies with the preassigned optical medium identification codes stored in write strategy table 18. Thus, optical disc drive 12 receives an optical medium that was developed after manufacture of the optical disc drive and applies a generic write strategy to write information to the optical medium by reading the identification code from the optical -.7-medium, matching the read identification code to a preassigned identification code of preassigned identification code, The optical disc manufacturer prepares general Wtito strategies based on the backwards compatibility of newer media and a look at existing ref ated media to find the closest fit to a planned medium. in one embodiment, related media have the same identification code except for a time stamp added at the end of the identification code that specifies the version of the media. In such an embodiment, infIrnnation is written to an optical medium by an assigned write strategy if the complete Identification code is present in the write strategy table and is written with a general write strategy if the version time stamp is not present with the general write strategy selected by the portion of the identification code that precedes the time stamp.

keferring now to Figure IA, the use of preassigned optical media identification codes for a manufacturer of an optical media is illustrated in an example of an optical disc drive write strategy table 18 for a CD-R or CD.RW drive. Three part ATIP start codes are associated with assigned and future planned optical media.

For each ATIP start code, the optical drive write strategy table has a write strategy including a write speed. The A'ITP start codes that are assigned to an existing optical medium of the manufacturer have a corresponding entry in write strategy table 18 with a write strategy developed by the optical disc drive manufacturer for that optical medium. The ATIP start codes that are preassigned to future planned optical media have a corresponding entry in write strategy table 18 of a general write strategy prepared by the optical disc drive manufacturer based on an analysis of the design parameters of the future optical media. lor instance, the optical disc drive manufacturer may use the write strategy of an optical medium having similar design parameters or may simply use the generic write strategy with a higher write speed.

Alternatively, if the identification code uses the time stamp implementation, the optical disc drive manufacturer implements an algorithm that finds a version of the optical medium by reference to the time stamp portion of the identification code that has an assigned write strategy and uses the assigned write strategy as the general write strategy. The write strategy for preassigned optical medium identification codes will select the lower of the planned maximum write speed of the optical medium or the maxiniuni iiit speed of the optical disc drive.

Referring now to Figure 2, a flow diagram depicts a method for writing information to an optical medium with a write strategy associated with a preassigned optical medium identification code. The process begins at step 20 with the reading of the optical medium identification code from the optical medium by the optical disc drive. At step 22, the read identigcation code is compared with the identification codes of the write strategy table to determine if the identification code is associated with an optical medium For instance, a detennluation is made of whether an identification code is in the write strategy table that matches the time stamp of the read identification code. If no, the process continues to step 24 to compare the read identification code with the identification codes of the write strategy table to detennine if the identification code is preassigned to a planned optical medium. For instance, a determination Is made of whether a match exists in the write strategy table for the first portion of the identification code but not the time stamp. If a match exists on the first portion, the assigned write strategy for that identification code portion with the most recent date stamp is selected as the general write strategy. If the result of steps 22 or 24 are yes, the process continues to step 26 to compare the write speed of the optical medium with the maximum write speed of the optical disc drive so that the write speed of the write strategy will not exceed the zna,thnum write speed of the optical disc drive. A result of yes at step 22 selects the write strategy from thc write strategy table that is associated with the optical medium assigned to the read identification code. A result of yes at step 24 selects the general write strategy from the ito strategy table that is associated with the planned optical mdiumpreassigned to the read identification code. If the result at step 24 is no, the process continues to step 28 for selection of the common generic write strategy. Selection of the common generic write strategy indicates, for Instance, that the read identification code is from an unknown optical media manufacturer.

Although the present invention has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the scope of the invention as defined by the appended claims. Jo

Claims

CLAIMS: 1. A method for writing information to an optical medium by an

optical drive, the method comprising: reading an identification code from the optical medium by the optical drive; selecting the write strategy associated with the identification code from a write strategy table of the optical drive if the identification code is assigned to an existing optical medium; selecting a general write strategy associated with the identification code from a general write strategy table of the optical drive if the identification code is pre-assigned to a planned optical medium, wherein the planned optical medium is released after the optical disk drive; and, writing information to the optical medium using the selected write strategy or the selected general write strategy.

2. The method of Claim 1, wherein the write strategy includes a write speed parameter.

3. The method of Claim I or Claim 2, wherein the optical medium identification code comprises an ATIP start code.

4. The method of any one of the preceding claims, further comprising associating the generic write strategy with an unknown optical medium lacking an assigned or preassigned optical medium identification code.

5. The method of any one of the preceding claims, comprising comparing the general write speed with the optical drive maximum write speed, and writing the information at the lesser of the general write speed and the optical drive maximum write speed.