Method and apparatus for disc drive data security using a servo wedge

Information

  • Patent Grant
  • 6771446
  • Patent Number
    6,771,446
  • Date Filed
    Wednesday, February 28, 2001
    23 years ago
  • Date Issued
    Tuesday, August 3, 2004
    19 years ago
Abstract
The present invention includes a method and apparatus to write and read copy protected data on a disc drive storage system using a servo wedge.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention generally relates to storing and retrieving copy-protected data on a disc drive.




2. Background of the Related Art




With the advent of the recording and playing of digital data, the need to store copy-protected data on disc drives becomes increasingly a necessity. Digital data is rapidly becoming the standard format by which industries, such as the entertainment industry, record and play multimedia. Paid for programming available to the public such as movies, sound tracks, music recordings, and the like, are increasing in demand. With digital recording, the public has more options than ever to listen to and/or record digital audio and video with unparalleled recording and playback quality.




One exemplary storage system being used more frequently to store digital multi-media is a computer controlled disc-based storage drive, e.g., a disc drive. Disc drives are capable of storing large amounts of digital data in a relatively small area. Disc drives store information on one or more recording media. The recording media conventionally take the form of a circular storage disc, e.g., media, having a plurality of recording tracks. Conventional disc drives include a plurality of the storage discs, vertically aligned, and each with at least one magnetic head for reading or writing information to the media. Typically, the magnetic head is attached to a positioner arm assembly that uses servomotors, such as stepper motors, to align the magnetic head above the disc. The location of the magnetic head is typically determined by a disc controller that is given the position of a data area on the disc to read or write data. The precise location of the head is typically accomplished by incorporating a closed-loop electro-mechanical servo system with a dedicated servo region, or regions, used to provide relatively continuous feedback to the system to maintain accurate positioning of the data heads.




Unfortunately, due to the high quality of the data and the fact that the data stored on digital storage systems, such as disc drives, is often unprotected and easily copied, the copying and selling of unauthorized copies of digitally recorded material is on the rise. Consider the case where a paid for program such as an audio file is downloaded via a network of computers such as the Internet, to a disc drive for play by a client who has paid for the file. Often, the file may be copied to another storage media or to another disc drive for use by another user unless copy protection is used. This often referred to as “pirating” a copy of the file. Additionally, the file may be repackaged and sold by others for profit without permission, often called “software piracy”. In addition, the files may be shared by other users by playing from the owner's computer allowing the end user the benefit of the file without purchasing the file from the owner.




Conventional digital copy-protection schemes involve techniques such as registration, encryption, digital watermarking, 5C content, and the like. For example, software copy protection schemes often involve the use of copy-protection techniques that require issuing registration numbers with each package. When you install the software, you must enter the registration number. This technique does not prevent all unauthorized copying, but it limits it. In addition, users may not be able to obtain updates to a software product unless they own the original diskettes and documentation. Unfortunately, the user may forget, or may have difficulty in registering the software and may become frustrated if the software stops working and/or working properly.




For conventional multimedia, data stored on optical surfaces such as found on a digital versatile disc (DVD) is often copy protected. For example, the digital-video format includes a content scrambling system (CSS) to prevent users from copying discs. The DVD system may also use key based techniques such as the SC technique that has software keys that expire after use. Unfortunately, this means that today's DVD players may not be able to play DVD-video discs without a software and/or hardware upgrade to decode the encrypted and/or keyed data even though the use may be authorized.




Another issue with conventional copy protection is that of making backups of the data. For example, a user may have a computer that they need to backup the data, conventional encryption techniques often require that a hardware and/or specific software key(s) be used before the data can be successfully copied. Unfortunately, the user may not have the correct hardware or software key to allow the transfer of the data and may become frustrated.




Furthermore, most conventional copy protection techniques such as CSS are defeated over time causing the digital-video and software industry to constantly upgrade the hardware, and/or software techniques to combat the unauthorized copying. The constant upgrading and development of protection techniques that are eventually exposed and defeated causes an increase in the cost of the product as well as possible incompatibility issues with existing systems.




Thus, what is needed is a method that allows the recording and playing of copy protected material to the user without the ability to copy the data or use the data in an unauthorized manner without affecting the compatibility of the storage device to operate with non-copy protected data.




SUMMARY OF THE INVENTION




The present invention generally provides a method and apparatus for storing and retrieving copy protected data within storage devices such as a disc drive. One aspect of the present invention provides a method for writing on a disc drive data to be copy protected, the steps include providing data to be copy protected, copying a first data table to a second data table writing the data to be copy protected to a least one data sector within at least a first data wedge and modifying, within the first data list, the status of at least one servo wedges adjacent and corresponding to the data wedge, as defective.




Another aspect of the invention provides a method for reading copy protected data from a disc drive, the steps include determining if a request to read copy protected data has been issued, and if the request to read copy protected data has not been issued then reading at least one first servo status from a first data table wherein the first servo status indicates the a servo wedge as defective, but, if the request to read copy protected data has been issued then reading a second servo status from a second data list which indicates the servo wedge as valid and reading the data from the corresponding data wedge.




One aspect of the present invention provides a disc drive system comprising a signal-bearing media means for storing data, a code memory means coupled to a read/write controller means for controlling the reading and writing of data to the signal-bearing media, a means for reading and writing the data to the signal-bearing media and a processor means coupled to the code memory and the read/write controller. The processor includes a program which, when executed on the processor for a write sequence, is configured to perform the steps of copying a first data table to a second data table, writing data to be copy protected to at least one data wedge of the signal-bearing media, and modifying, within the first data table, the status of at least one servo wedge corresponding to the data wedge, as defective. When the program is executed on the processor for a read sequence, is configured to perform the steps of determining if a request to read copy protected data has been issued, if the request to read copy protected data has not been issued then reading at least one first servo wedge status from the first data table wherein the servo status indicates the location of the data as defective, but, if the request to read copy protected data has been issued then reading a second servo wedge status data from the second data table wherein the servo status indicates the location of the data as valid and reading the data.











BRIEF DESCRIPTION OF THE DRAWINGS




So that the manner in which the above recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.




Other features and advantages of the invention will become apparent to a person of skill in this field who studies the following description of an embodiment given below in association with the following drawings.





FIG. 1

is a plan view of a typical disc-based apparatus for reading and writing data on a media wherein the present invention may be used to advantage.





FIG. 2

is a plan view of typical media for storing data wherein the present invention may be used to advantage.





FIG. 3

illustrates a memory core for storing programming data in which the present invention may be used to advantage.





FIG. 4

is a flow diagram of a method for a start-up sequence for the disc-based apparatus of

FIG. 1

in accordance with the present invention.





FIG. 5

is a flow diagram of a method for a write sequence for the disc-based apparatus of

FIG. 1

in accordance with the present invention.





FIG. 6

is a flow diagram of a method for a read sequence for the disc-based apparatus of

FIG. 1

in accordance with the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Embodiments of the invention have particular advantages in electronic data storage systems. One exemplary electronic data storage system commonly used in the computer industry, well suited for supporting the digital data copy protection method described herein, is known as a disc drive. As will be described below, aspects of the preferred embodiment pertain to specific method steps implementable on computer disc-drive systems.




In one embodiment, the invention may be implemented as part of a computer program-product for use with computer disc-drive systems. The programs defining the functions of a preferred embodiment can be provided to the disc drive via a variety of signal-bearing media, which include but are not limited to, (i) information permanently stored on non-writable storage media (e.g. read-only memory devices within a computer such as read only CD-ROM disks readable by a CD-ROM or DVD drive; (ii) alterable information stored on a writable storage media (e.g. floppy disks within diskette drive or hard-disc drive); or (iii) information conveyed to a computer by communications medium, such as through a computer or telephone network, including wireless communication. Such signal-bearing media, when carrying computer-readable instructions that direct the functions of the present invention, represent alternative embodiments of the present invention. It may also be noted that portions of the product program may be developed and implemented independently, but when combined together are embodiments of the present invention.





FIG. 1

is a plan view of a typical disc-based apparatus for reading and writing data on a media wherein the present invention may be used to advantage.

FIG. 1

illustrates one embodiment of the invention including disc drive electronics


30


which in general includes an interface


39


adapted to receive external signals and data, and a Head Disc Assembly Interface (HDAI)


38


for connecting the disc drive electronics


30


to the head disc assembly (HD)


82


. The HD


82


includes read/write transducer head(s)


40


coupled via wires


46


to the HDIA


38


, a spindle motor


41


, an actuator arm


49


, a servo actuator


47


, and other disc drive components that are well known in the art. The read/write transducer head(s)


40


are mounted on the actuator arm


49


. As the servo actuator


47


moves the actuator arm


49


, the read/write transducer head(s)


40


fly above a media


50


to read and write data to the media


50


. The media


50


typically includes a disc or discs coated with a recording material such as ferrous iron, magneto-optical media, and other materials adapted to hold a magnetic charge. Media


50


may also include optical media such as a DVD adapted to optically store digital information. A set top box


80


, coupled to interface


39


, is used to communicate with video and audio sources such as digital cable TV systems, digital satellite, and the like and is adapted to handshake with the disc drive electronics


30


so as to control the inflow/outflow and protection of copy protected data. The step top box


80


is of any conventional design adapted to receive digital information and transmit the information to the interface, and communicate with the disc drive electronics


30


through interface


39


to interface/disc/servo controller


31


. The set top box may communicate with the interface through any conventional communication mode such as SCSI, ATA, serial, IEEE 488, and any other form of electronic data transfer. Illustrative multimedia formats include audio files (e.g., AU, WAV, AIFF, MIDI, MP3), video files (e.g., MPEG, AVI), image files (GIF, JPEG, XBM, TIFF, PICT, Raster file) and other formats known in the art.




The interface/disc/servo controller


31


provides a translation and command interface between the set top box


80


and disc drive electronics


30


through the interface


39


. The interface/disc/servo controller


31


is directly connected to the buffer memory


32


through a memory bus connection


66


. The buffer memory


32


may store program code and/or data for use with the operation of the drive. Interface/disc/servo controller


31


is also connected via a read/write bus


44


to CPU


34


used for processing the disc drive commands, the code memory


35


is adapted to store operational data and commands, and the servo power electronics


36


are adapted to operate the servomotor


41


and actuator arm


49


. Servo power electronics


36


are typically connected to the HD


82


via servo control connection


84


to a plurality of FET switches


37


that control the spin motor


41


. The HDAI


38


provides an electrical connection between the printed circuit board assembly (PCBA)


84


including the internal disc drive electronics


30


, and the HD


82


including the disc drive internal mechanical and electromechanical components. Read/write channel electronics


33


used to transmit data to and from the media


50


via data bus


42


include read write logic


33




a


, write logic


33




b


, and servo logic


33




c


, and includes a connection to the interface/disc/servo controller


31


through data bus


42


. A serial bus


43


is also used to send configuration commands from the CPU


34


to the read/write channel electronics


33


.





FIG. 1

is merely one hardware configuration for a disc-drive data storage system. A preferred embodiment of the present invention can apply to any comparable hardware configuration, regardless of whether the disc-drive data storage apparatus is a complicated, multi-media storage apparatus including a plurality of media types, or a single disc-drive data storage apparatus.





FIG. 2

is a plan view of the media


50


for storing data wherein the present invention may be used to advantage.

FIG. 2

illustrates exemplary data storage tracks


208


on the media


50


including data wedges


210


separated by a plurality of servo wedges


220


in accordance to the present invention. As necessary,

FIG. 1

is referenced in the following discussion of FIG.


2


. For clarity, only portions of the tracks


208


are shown. Illustratively, a plurality of concentric tracks


208


are shown representing a plurality of data wedges


210


and servo wedges


220


extending across the media for data storage and retrieval by the read/write head(s)


40


. As the read/write head(s)


40


fly over the media


50


, the servo actuator


47


moves the actuator arm


49


and read/write head(s)


40


to a particular track


208


on the media


50


in response from commands of the interface/disc/servo controller


31


. The data wedges


210


are generally used for storing external data from an external user such as multimedia files and are generally accessible by the user through the interface


39


. Several adjacent tracks


208


can be combined together to create a “zone” of tracks


208


with similar data densities. The “zone” may represent several data wedges


210


. Servo wedges


220


are portions of each track


208


that may include read/write head(s) alignment indicia, physical address information, and check pointing data used for defect management. Servo wedge data is generally for the drive use and is generally inaccessible to the outside user.





FIG. 3

illustrates the code memory


35


for storing programming data in which the present invention may be used to advantage. The code memory


35


is preferably random access memory sufficiently large to hold the necessary programming and data structures of the invention. The code memory


35


may be used to store operating code, and other run-time code that enables the drive. The contents of the code memory


35


may also be stored to a plurality of reserved areas of the media


50


or into other areas of the drive electronics


30


such as buffer memory


32


for redundancy.




The code memory


35


further includes a logical to physical translation program


345


adapted to transform logical block addresses (LBA) to physical media coordinates. Data communicated to and from a data storage system is normally managed by the LBA rather than by physical address. Data sectors are numbered blocks of data to be stored and retrieved. Data sectors are the fundamental units of data handled by the data storage system and are usually of fixed length, e.g., 512 bytes. In one aspect of the invention, one data sector equals the length of one data wedge


210


. However, if the data wedges


210


are large, as is often the case with magnetic storage systems, several logical addressed data sectors may be stored in a single physical data wedge


210


. The physical translation program


345


coordinates the translation of the logical address of a particular block of data to the physical address of the location at which the data is stored.




The coordination between logical addressing and physical addressing is complicated by defects in the recording material in which the data cannot be reliable stored and retrieved. Defects should therefore be skipped, that is, no attempt should be made to either write to or read from them. The details of one exemplar defect management method and apparatus is disclosed in U.S. patent application Ser. No. 09/241,795, entitled “Apparatus and Method for Efficient Defect Management In a Magneto-Optical data Storage System,” Belser et al., filed on Feb. 1, 1999, which is incorporated herein by reference in its entirety.




During manufacture, the recording media


50


is usually written to and then read back from to determine which physical addresses are defective. As part of the process of converting a logical block address to a physical location on the media


50


two lists are stored in code memory


35


, a manufacturer's defect list


305


(e.g., table) and a physical descriptor table


308


(e.g., list). The physical descriptor table


308


generally includes servo data that indicates how many bytes of data may be written between each servo wedge


220


and may indicate if the servo wedge


220


is to be skipped. Additionally, the physical descriptor tables


305


may indicate that a zone needs to be skipped as there may be a very large defect in the media


50


covering more than one data wedge


210


within a zone. To skip a zone, the descriptor table “folds a wedge out” by indicating that the sets of servo wedges


220


adjacent each side of the defective zone, i.e. the wedges that subtend the zone, are defective, thereby skipping all of the data sectors within a zone. The manufacture's defect list


305


, i.e., the drive's defect list, maps the defect relationship between logical and physical addresses between the non-defective physical addresses and logical addresses, and is stored on the media


50


by the manufacture and loaded into the code memory


35


during operation. Additionally, as the media


50


is used, other defects may occur through, for example, the read/write head(s)


40


inadvertently touching the surface of the media


50


during a read and/or write operation and physically damaging a data sector on the media


50


. Media defects subsequent to the manufacturer's defect list


305


are placed in the manufacturer's defect grown list


315


. Thus, the manufacturer's defect grown list


315


literally “grows” as the media


50


is used. The logical to physical translator program


345


uses the physical descriptor table


308


, the manufacturer's defect list


305


, and manufacturer's defect grown list


315


to determine if the requested sector(s) have moved due to defects during a read or write sequence. The code memory


35


also includes an address pointer


322


used to point the logical to physical translation program


345


to the physical descriptor table


308


or to the copy of the physical descriptor table


312


.




The code memory


35


further includes the copy protection program


325


used to allow the reading and writing of copy-protected data. The copy protection program


325


generally includes code specific to the operation of the copy-protection scheme such as a servo defect handler


327


code. The servo defect handler code


327


is used to determine defective servo wedges


220


and instructing the address pointer


322


to point to the physical descriptor table


308


if the copy protection program


325


is not called or to point to the copy of the physical descriptor table


312


if the copy protection program


325


is called. While code memory


35


is shown as a single entity, it should be understood that code memory


35


may in fact may be volatile or non-volatile, comprise a plurality of modules, and that the code memory


35


may exist at multiple levels, from high speed registers and caches to lower speed but larger DRAM chips.





FIG. 4

is a flow diagram of a method


400


for a start-up sequence for the disc-based apparatus of

FIG. 1

in accordance with the present invention. As necessary,

FIGS. 1-3

are referenced in the following discussion of FIG.


4


.





FIG. 4

is entered at step


405


when for example the set top box


80


instructs the disc drive electronics


30


to read or write data to media


50


. At step


410


, the interface/disc/servo controller


31


initializes the disc drive electronics


30


, CPU


34


, the code memory


35


, the servo power


36


, FETs


37


, the read/write channels


33


, and the buffer memory


32


and begins the process of “spinning”, i.e., rotating, the media


50


up to prepare the media


50


for a read or write operation. At step


415


, the method


400


determines whether the servomotor


41


is functioning properly. If the servomotor


41


is working improperly, the method


400


proceeds to step


420


and spins the servomotor


41


down. If the servomotor


41


is functioning properly, the method


400


proceeds to step


425


. At step


425


, the actuator arm


49


positions the read/write transducer head(s)


40


and reads the manufacturer's defect list


305


, physical descriptor table


308


, and the copy of the physical descriptor table


322


list stored within a reserved area within memory and/or on the drive media


50


such as a reserved area on a servo wedge


220


. At step


430


, run-time code such as the address pointer


322


is loaded into the code memory


35


from the media


50


and/or memory into a separate data location to allow the normal operation of the drive. At step


435


, the copy protection program


325


is loaded into code memory


35


from the media


50


and/or memory.




At step


440


, method


400


determines if the media


50


is properly formatted to receive data from the read/write transducer head(s)


40


. If the media


50


is not properly formatted, then method


400


proceeds to step


445


to set the read/write commands as invalid and then proceeds to step


450


. If the media


50


is properly formatted, then method


400


proceeds to step


450


. At step


450


, the method


400


determines whether the copy protection program


325


has been called, e.g., the copy protection program


325


was called from the set top box


80


. If the copy protection program


325


has not been called, then method


400


proceeds to step


480


. If the copy protection program


325


has been called, then method


400


proceeds to step


455


and initializes the copy protection program


325


. At step


460


, the method


400


determines whether a copy of the physical descriptor table


312


has been loaded and is available. If the method


400


determines that the physical descriptor table


312


has been loaded then method


400


proceeds to step


480


. If the physical descriptor table


312


has not been loaded then the method


400


proceeds to step


465


and copies the physical descriptor table


308


. At step


480


, method


400


receives a read or a write command. If the read/write commands at step


480


where set to invalid from step


445


, then the drive would be unable to be used for storing or retrieving data from the data wedges


210


. If the read/write commands are set to valid, the method


400


waits for a read or write command.





FIG. 5

is a flow diagram of a method


500


for a method of writing data on the media


50


of

FIGS. 1 and 2

in accordance with the present invention. As necessary,

FIGS. 1-4

are referenced in the following discussion of FIG.


5


.





FIG. 5

is entered at step


505


when a write command is received at step


480


. At step


510


, the read/write head(s)


40


are positioned by actuator arm


49


in response to interface/disc/servo controller


31


and data is written onto the media


50


. At step


510


, the method


500


converts the logical addresses to physical address using the logical to physical address translation program


345


and writes the data to the appropriate sectors on the media


50


. At step


515


, method


500


determines whether a copy protection command via interface


39


called the copy protection program


325


. In one aspect, the set top box


80


issues the copy protection command to the interface/disc/servo controller


31


. If the command for copy protection was not received and/or not understood, the method


500


proceeds to step


525


. If the command for copy protection was received, the method


500


proceeds to step


520


. At step


520


, the method


500


modifies the physical descriptor table


308


to map out the data wedge


210


between two consecutive servo wedges


220


where the copy protected data was written to, as defective, i.e., by folding a data wedge out. In one embodiment, only some of the data is written to the mapped out wedge to decrease the processing time and minimize the servo defect list data within the physical descriptor table


308


. Subsequently, method


500


proceeds to step


525


. At step


525


, method


500


determines if the write sequence has ended. If the sequence has ended, method


500


exits at


530


. If the write sequence has not ended, then method


500


returns to step


510


and continues the write sequence. Thus, if the copy protection program


325


was not called, the data may be normally written, and if the data protection program


325


was called, the data sectors written are skipped by folding a data wedge


210


where some, or all, of the copy protected data is located.





FIG. 6

is a flow diagram of a method


600


for a method of reading data from the media


50


of

FIGS. 1 and 2

in accordance with the present invention. As necessary,

FIGS. 1-5

are referenced in the following discussion of FIG.


6


.





FIG. 6

is entered at step


605


when a read command is received at step


480


. At step


610


, method


600


determines if the copy protection program


325


was called. If the copy protection program


325


was not called then method


600


proceeds to step


615


and uses the physical descriptor table


308


by setting the address pointer


322


to point to the physical descriptor table


308


that has been modified from step


520


, i.e., a data wedge was folded out. Method


600


proceeds to step


625


described below to read the data. If the copy protection program


325


was called, then the method


600


proceeds to step


620


. At step


620


, method


600


sets the address pointer


322


to point to the unmodified copy of the physical descriptor table


312


to read the data wherein the data wedge(s)


210


storing the copy protected data are not folded out. At step


625


, method


600


converts the logical addresses to physical address using the logical to physical address translation program


330


and then reads the data. If the data being read was written as copy protected from method


500


and the copy protection program


325


was called, then the data reads normally as the data wedges are not folded. From step


620


, if the data being read was written as copy protected from method


500


, and the copy protection program


325


was not called, then the data reads sector


305


indicates that the data sector locations of the copy protected material as bad e.g., “sector(s) not found”. At step


630


, method


600


determines if the read sequence has ended. If the read sequence has ended, the method


600


proceeds to step


635


described below. If the read sequence has not ended, the method


600


proceeds to step


625


and continues to read the data. At step


635


, the address pointer


322


is set to point to the physical descriptor table


308


and exits at step


640


. Thus, an unauthorized user would not be able to read the data from the disc drive as the copy protected data wedge


210


is skipped.




In summary, the present invention generally provides a method and apparatus for storing and retrieving copy protected data within storage devices such as a disc drive. One embodiment of the present invention provides a method


500


for writing on a disc drive data to be copy protected, the steps include providing data to be copy protected


505


, copying a first data table, such as physical descriptor table


308


to a second data table, such as the copy of the physical descriptor table


312


, writing the data to be copy protected to a least one data sector within at least a first data wedge


210


and modifying, within the first data table, the status of at least one servo wedge


220


corresponding to and adjacent the data wedge


210


as defective. In another aspect, the step of modifying comprises, within the first data table, i.e., physical descriptor table


308


, modifying two consecutive servo wedges


220


subtending the data wedge as defective. In addition, before the step of providing data to be written, a step includes providing a copy protection command signal


455


. The step of providing a copy protection command signal is a user selectable step


450


. In one aspect, the first and second tables comprise the physical descriptor table


308


. The second table comprises a copy of the physical descriptor table


312


. IN one aspect, the physical descriptor table


308


comprises servo defect data. In another aspect, the step


510


of writing the data to at least a second and third data wedge


210


defining a zone of data wedges


210


, modifying, within the first data table, i.e., physical descriptor table


308


, the status of the servo wedges


220


subtending the zone of data wedges


220


as defective, wherein the second data wedge


210


is subtended by a second set of servo wedges


220


and the third data wedge


210


is subtended by a third set of servo wedges


220


. In another aspect, the data wedges


210


are defined by a logical block address.




Another embodiment of the invention provides a method for reading


625


copy protected data from a disc drive, the steps include determining if a request to read copy protected data has been issued


610


, and if the request to read copy protected data has not been issued then reading


625


at least one data servo status from a first data table, i.e., physical descriptor table


308


, where the servo status indicates the data wedge


210


as defective, but, if the request to read copy protected data has been issued then reading a second servo status from a second data table, i.e., the copy of the physical descriptor table


312


, which indicates the servo wedge


220


as valid and reading the data from the data wedge


210


corresponding to the servo wedge


220


. In one aspect, the first and second tables comprise the physical descriptor table


308


. The second table comprises a copy of the physical descriptor table


312


. In addition, the physical descriptor table


308


may comprises servo defect data.




One embodiment of the present invention provides a disc drive system comprising a signal-bearing media means


50


for storing data, a code memory means


35


coupled to a read/write controller means


31


for controlling the reading and writing of data to the signal-bearing media


50


, a means for reading and writing the data to the signal-bearing media


50


and a processor means


34


coupled to the code memory


35


and the read/write controller


31


. The processor


34


includes a program


500


which, when executed on the processor


34


for a write sequence, is configured to perform the steps of copying a first data table to a second data table, i.e., physical descriptor table


308


, writing data


510


, to be copy protected to at least one data wedge


210


of the signal-bearing media


50


, and modifying


520


, within the first data table, the status of at least one of a first set of consecutive servo wedges


220


subtending the data wedge


210


, as defective. When the program


600


is executed on the processor


34


for a read sequence, is configured to perform the steps of determining


610


if a request to read copy protected data has been issued, if the request to read copy protected data has not been issued then reading


625


at least one servo wedge status from the first data table, i.e., physical descriptor table


308


, where the servo status indicates the location of the data as defective, but, if the request to read copy protected data has been issued then reading the servo wedge status data from the second data table, i.e., copy of physical descriptor table


312


, where the servo status indicates the location of the data as valid and reading the data.




Although various embodiments which incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments within the scope of the present invention. For example, it is contemplated that the copy protection program


325


may be integral to the overall drive code, or may be an impendent module within code memory. Alternatively, the copy protection program


325


may be partially stored external to the drive and downloaded through the interface


39


.




While foregoing is directed to the preferred embodiment of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.



Claims
  • 1. A method for writing on a disc drive data that is copy protectable, comprising:providing data that is copy protectable; copying a first data table to a second data table; writing the data that is copy protectable to a least one data sector within at least a first data wedge; and modifying, within the first data table, the status of at least one servo wedge corresponding to and adjacent the data wedge as defective.
  • 2. The method of claim 1, wherein the step of modifying comprises, within the first data table, modifying two consecutive servo wedges subtending the data wedge as defective.
  • 3. The method of claim 1, wherein the first and second table comprise a physical descriptor table.
  • 4. The method of claim 3, wherein the second table comprises a copy of the physical descriptor table.
  • 5. The method of claim 3, wherein the physical descriptor table comprises servo defect data.
  • 6. The method of claim 1, wherein prior to the step of providing data, a copy protection command signal is provided.
  • 7. The method of claim 1, further comprising the step of writing the data to at least a second and third data wedge defining a zone of data wedges, modifying, within the first data table, the status of the servo wedges subtending the zone of data wedges as defective, wherein the second data wedge is subtended by a second set of servo wedges and the third data wedge is subtended by a third set of servo wedges.
  • 8. The method of claim 7, wherein the data wedges are defined by a logical block address.
  • 9. A method for reading copy protected data from a disc drive, comprising:determining if a request to read copy protected data has been issued; if the request to read copy protected data has not been issued then reading at least one first servo status from a first data table wherein the first servo status indicates servo wedge as defective; and if the request to read copy protected data has been issued then reading a second servo status from a second data table that indicates the servo wedge as valid and reading the data from a data wedge corresponding to and adjacent the servo wedge.
  • 10. The method of claim 9, wherein the first and second table comprises a physical descriptor table.
  • 11. The method of claim 10, wherein the second table comprises a copy of the physical descriptor table.
  • 12. The method of claim 10, wherein the first table comprises a physical descriptor table comprising servo wedge data.
  • 13. The method of claim 9, wherein the first servo status indicates skipping the data wedge containing the data.
  • 14. The method of claim 9, wherein the first servo status indicates that two consecutive servo wedges subtending the data wedge are defective.
  • 15. A disc drive system comprising:a signal-bearing media for storing data; code memory means coupled to a read/write controller means for controlling the reading and writing of data to the signal-bearing media; means for reading and writing the data to the signal-bearing media; and processor means coupled to the code memory means and the read/write controller means for writing and reading copy protectable data to and from the media; wherein if a request to read copy protected data has not been issued then reading at least one first servo status from a first data table wherein the first servo status indicates a servo wedge as defective, and if the request to read copy protected data has been issued then reading a second servo status from a second data table that indicates the servo wedge as valid and reading the data from a data wedge corresponding to and adjacent the servo wedge.
  • 16. The system of claim 15, wherein the processor comprises a program which, when executed on the processor for a write sequence, is configured to perform the steps comprising:copying a first data table to a second data table; writing data that is copy protectable to at least one data wedge of the signal-bearing media; and modifying, within the first data table, the status of at least one of a first set of consecutive servo wedges subtending the data wedge as defective; wherein, when the program is executed on the processors for a read sequence, it is configured to perform the steps of: determining if a request to read copy protected data has been issued, if the request to read copy protected data has not been issued then reading at least one servo wedge status from the first data table wherein the servo status indicates the location of the data as defective, and if the request to read copy protected data has been issued then reading the servo wedge status data from the second data table wherein the servo status indicates the location of the data as valid and reading the data.
  • 17. The system of claim 16, wherein the step of modifying the status comprises the step of marking at least one servo wedge as defective.
  • 18. The system of claim 16, wherein the code memory means is selected from the group consisting of volatile memory and non-volatile memory and media.
  • 19. The system of claim 16, wherein the means for reading and writing the data to the signal-bearing media comprises at least one read/write head adapted to read and write data to the media.
  • 20. The system of claim 16, wherein the first and second table comprises a physical descriptor table.
CROSS-REFERENCE TO A RELATED APPLICATION

This invention is based on U.S. Provisional Patent Application Serial No. 60/185,441 filed Feb. 28, 2000, entitled Fold Wedges To Hide Copy-Protected Data filed in the name of Gayle L. Noble. The priority of this provisional application is hereby claimed. U.S. Patent application entitled “Method and Apparatus for Disc Drive Data Security Using a Defect list”, Ser. No. 09/795,877 filed on Feb. 28, 2001, filed in the name of Gayle L. Noble is hereby incorporated herein by reference in its entirety. U.S. Patent application entitled “Method and Apparatus for Disc Drive Data Security Using Physical Location”, Ser. No. 09/795,623 filed on Feb. 28, 2001, filed in the name of Gayle L. Noble is hereby incorporated herein by reference in its entirety.

US Referenced Citations (3)
Number Name Date Kind
5799145 Imai et al. Aug 1998 A
6052781 Weber Apr 2000 A
6397270 Cheswick May 2002 B1
Provisional Applications (1)
Number Date Country
60/185441 Feb 2000 US