Data Verification Patents (Class 360/53)
  • Patent number: 8081396
    Abstract: A device for processing data recorded on a tape medium includes a first control part that controls a read head to read specific data recorded in a first area among data recorded in a first format on the tape medium. Data in the first format is recorded at a first recording density. The device further includes a second control part that controls a write head to write the specific data in a second area different from the first area of the tape medium and to write the specific data in a second format in a third area different from the second area of the tape medium. Data in the second format is recorded at a second recording density different from the first recording density. Moreover, the device may include a recording part for recording specific information that specifies a read position of other data among data recorded in the first format on the tape medium.
    Type: Grant
    Filed: August 10, 2009
    Date of Patent: December 20, 2011
    Assignee: International Business Machines Corporation
    Inventors: Takashi Katagiri, Yutaka Oishi
  • Patent number: 8059353
    Abstract: A magnetic storage system includes a disk, a head, an actuator, a read channel, and a main controller. The main controller causes the head to read a data block of a selected track of the disk at each of a plurality of fixed offsets from a center of the selected track. The main controller samples a gain in the read channel a plurality of times while the head is reading the data block at each of the plurality of fixed offsets to obtain a plurality of gain samples for each of the plurality of fixed offsets. If the data block was written off-track with a non-constant offset, the main controller determines an approximate starting position and an approximate rate of change of an off-track deviation of the data block based on the plurality of gain samples for the plurality of fixed offsets.
    Type: Grant
    Filed: August 25, 2008
    Date of Patent: November 15, 2011
    Assignee: Seagate Technology LLC
    Inventor: Michael Chen
  • Patent number: 8049980
    Abstract: A mass data storage system including a hard disk drive comprising heads and platter surfaces determines when a head of the disk is faulty and the disk continues to operate as a partially failed disk with respect to the remaining heads which are not faulty. A striped parity disk array comprises disks capable of operating as partially failed disks allows copying of data from the platter surfaces not associated with a faulty head of a partially failed disk to a spare disk which reduces the amount of data that must be rebuilt in the rebuild process, thereby reducing the amount of time the array spends in degraded mode exposed to a total loss of data caused by a subsequent disk failure.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: November 1, 2011
    Assignee: Network Appliance, Inc.
    Inventor: Tim K. Emami
  • Patent number: 8045285
    Abstract: In an implementation, a media drive includes bit patterned magnetic media and a module. The module is to cause data encoded by one or more error correction codes to be written on the bit patterned magnetic media with a constraint that is configured to be used to synchronize the data if a bit insertion or deletion occurs.
    Type: Grant
    Filed: February 19, 2009
    Date of Patent: October 25, 2011
    Assignee: Marvell International Ltd.
    Inventors: Xueshi Yang, Gregory Burd
  • Patent number: 8033008
    Abstract: A defect inspection is performed for each of glass substrates by a surface defect detector. The distance from the center of the glass substrate to a detected defect, as a radius of a nonmagnetic region to be formed circular, is recorded along with an ID assigned to the glass substrate. Such defect information is recorded in a defect list using a printer or recorded in an RFID tag using an RFID writer. The defect list or the RFID tag is attached to a glass-substrate case. Each glass substrate and its defect information are in one-to-one correspondence and are provided to a customer as a magnetic disk manufacturer. Based on the obtained defect information, the customer manufactures magnetic disks each being a discrete track recording medium having the nonmagnetic region formed at the position where the defect is present.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: October 11, 2011
    Assignees: Hoya Corporation, Hoya Glass Disk (thailand) Ltd.
    Inventors: Hiroshi Takeda, Ken-ichi Nishimori, Tomotaka Yokoyama, Tadashi Tomonaga
  • Patent number: 8027120
    Abstract: A magnetic tape device comprises a plurality of magnetic heads for recording or reproducing data to a magnetic tape including a data recording area, a tape running mechanism for making the magnetic tape run on the magnetic heads, and a controller for controlling a recording and reproducing operation of the magnetic heads for the magnetic tape while running. The controller includes a recording controller to control the recording and reproducing operation of the magnetic heads so as to record recording target data including a redundancy without recording the recording data and data which is the same as at least a part of the recording target data as redundant data, these data not being recorded in data recording areas adjacent with each other.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: September 27, 2011
    Assignee: NEC Corporation
    Inventor: Kenji Kubota
  • Publication number: 20110222183
    Abstract: A method according to one embodiment includes: deciding to perform a refresh operation on a media cartridge having a tape wrapped around a spool; determining which drive of a plurality of drives is available to perform the refresh operation; causing the media cartridge to be mounted to the available drive; causing the drive to unwrap the tape from the spool of the media cartridge to about an end of the tape; and causing the drive to wrap the tape back onto the spool after the unwrapping, wherein at least some data on the tape is overwritten with new data, and a verification operation is performed using the new data.
    Type: Application
    Filed: May 24, 2011
    Publication date: September 15, 2011
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Scott Milton Fry, Reed Alan Hancock, James Mitchell Karp, Pamela Ruth Nylander-Hill, Eiji Ogura
  • Publication number: 20110205654
    Abstract: A control apparatus for controlling initialization of data stored in a storage unit in response to receipt of an initialization instruction from a host system, includes (a) a register unit that stores inversion bit information indicating a plurality of bits to be inverted in data readout process, (b) a data receiving unit that receives read data and an error correcting code corresponding to the read data, and (c) an inversion unit that inverts part of bits of at least one of the read data and the error correcting code corresponding to the read data on the basis of the inversion bit information in the data readout process after the receipt of the initialization instruction. In the above (a), the plurality of bits to be inverted being part of bits of at least one of read data and an error correcting code corresponding to the read data.
    Type: Application
    Filed: February 2, 2011
    Publication date: August 25, 2011
    Applicant: FUJITSU LIMITED
    Inventor: Hiroshi SAKURAI
  • Patent number: 8004785
    Abstract: A disk drive is disclosed comprising a disk having a plurality of data sectors, wherein a physical block address (PBA) is associated with each data sector. When a write command is received from a host to write user data to the disk, and the write command comprises an unformatted logical block address (LBA), the user data is written to a first data sector, and the first data sector is write verified. A second data sector is defect scanned, and after the second data sector passes the defect scan, the user data is migrated from the first data sector to the second data sector and the LBA is formatted to the second data sector.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: August 23, 2011
    Assignee: Western Digital Technologies, Inc.
    Inventors: Chun Sei Tsai, William B. Boyle, Carl E. Barlow, Kenneth J. Smith
  • Patent number: 8000052
    Abstract: A method according to one embodiment of the present invention includes receiving an instruction to perform a verification operation on a media cartridge having a tape wrapped around a spool; unwrapping at least some of the tape from the spool of the media cartridge; after the unwrapping, wrapping at least some of the tape back onto the spool; during at least one of the unwrapping and wrapping (and preferably both, and possibly over several cycles of unwrapping and wrapping), performing a verification operation; generating a quality metric based on the verification operation; and outputting the quality metric or derivative thereof, such as a pass or fail indication; an instruction to set a pass/fail flag; a number, score or graphic illustrating to a user a general quality of the tape, etc. Additional methods and systems are also presented.
    Type: Grant
    Filed: August 11, 2008
    Date of Patent: August 16, 2011
    Assignee: International Business Machines Corporation
    Inventors: Scott Milton Fry, Reed Alan Hancock, James Mitchell Karp, Pamela Ruth Nylander-Hill, Eiji Ogura
  • Publication number: 20110194205
    Abstract: A method of managing defects of a recording medium of a data storage device includes performing a quality test related to occurrence of errors for each data sector in the recording medium; classifying a quality of each data sector according to evaluation criteria corresponding to quality classifications based on the quality test; determining a number of data sectors in each quality classification; and defect-processing the data sectors of the quality classifications that range from a lowest quality classification to a highest quality classification within a defect management limitation of the data storage device.
    Type: Application
    Filed: February 10, 2011
    Publication date: August 11, 2011
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Hwa-jun Kim, Jae-deog Cho
  • Patent number: 7995300
    Abstract: A plurality of tape drives writes a plurality of indicators corresponding to a plurality of data units on a tape, wherein an indicator indicates which tape drive of the plurality of tape drives has written a corresponding data unit on the tape. Each of the plurality of tape drives generates an extent of read errors, in response to reading the plurality of data units written on the tape. The extent of read errors generated by each of the plurality of tape drives are aggregated at a computational device coupled to the plurality of tape drives. A determination is made at the computational device of a defective tape drive of the plurality of tape drives from the aggregated extent of read errors.
    Type: Grant
    Filed: August 6, 2010
    Date of Patent: August 9, 2011
    Assignee: International Business Machines Corporation
    Inventors: Scott Milton Fry, Hiroshi Itagaki, James Mitchell Karp, Takashi Katagiri, Pamela Ruth Nylander-Hill, Yutaka Ooishi
  • Patent number: 7990645
    Abstract: Provided is a magnetic recording apparatus including a magnetic recording medium having a magnetic recording position patterned of a magnetic substance and a read head reading information from the magnetic recording medium, wherein the magnetic recording medium includes: a data area having the magnetic recording position patterned including a plurality of data tracks; and a servo area including a servo burst for tracking the data tracks, wherein the servo burst includes a plurality of bursts deviating from one another in a downtrack direction, and a width of each of the bursts is equal to or greater than a width of the read head and narrower than twice the width of the read head. According to this structure, although data is reproduced using a read head having a greater width than a width of each of data tracks, a linear section in which an output voltage is reduced depending on a size of an off-track is formed. As a result, a dead zone can be removed.
    Type: Grant
    Filed: March 25, 2008
    Date of Patent: August 2, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-su Kim
  • Patent number: 7986480
    Abstract: Embodiments of the present invention recite a method of preserving data on a hard disk drive. In one embodiment, a first copy of data is read from at least one sector of a hard disk drive and stored in a first location. A second copy of the data is stored in a non-volatile memory location of the hard disk drive. The first copy of the data is then modified to create a modified copy. The second copy of the data is then used to verify that the modified copy of data has been correctly written to the at least one sector of the hard disk drive.
    Type: Grant
    Filed: November 3, 2005
    Date of Patent: July 26, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Daniel J. Colegrove, Richard M. H. New
  • Patent number: 7974029
    Abstract: A disk drive is disclosed comprising a disk comprising a plurality of tracks, and a head actuated over the disk. A plurality of refresh zones are defined, wherein each refresh zone corresponds to a plurality of the tracks. Data is written to a first refresh zone, and a first zone counter is updated for a second refresh zone at a first rate. Data is written to a third refresh zone, and the first zone counter is updated for the second refresh zone at a second rate different than the first rate.
    Type: Grant
    Filed: July 31, 2009
    Date of Patent: July 5, 2011
    Assignee: Western Digital Technologies, Inc.
    Inventors: Chun Sei Tsai, Sang Huynh, Anthony L. Pei, Don Brunnett, Jahangir John Kasraee, Kent W. Gibbons
  • Patent number: 7974338
    Abstract: To improve the user experience, a digital radio receiver may output the data contained within the Fast Access Channel and Service Description Channel of a Digital Radio Mondiale stream when their decoding is complete without waiting for the Main Service Channel decoding to finish. When the Main Service Channel decoding is finished, the digital radio receiver may output the audio or data contained within the Main Service Channel. The audio or data from the Digital Radio Mondiale stream may be output on a speaker, headphones, a display, or other type of transducer. The digital radio receiver may also include a processor and a memory to store data from the Fast Access Channel and the Service Description Channel, including data from previously received Digital Radio Mondiale streams.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: July 5, 2011
    Assignee: Harman Becker Automotive Systems GmbH
    Inventors: Karl Anton Becker, Norbert Irnich
  • Patent number: 7974034
    Abstract: Systems and methods for detecting and designing enhanced disk sync marks using correlation detection are disclosed. The enhanced sync marks provide better noise immunity and higher detection rates over traditional Viterbi-based detection schemes even with a shorter sync mark length. The disk sync mark may provide optimal noise immunity for a particular target polynomial or a plurality of common target polynomials. The minimum Euclidean distance between a candidate sync mark and a plurality of right-shifted versions of the candidate sync mark is computed and compared with other candidate sync marks. The sync mark with the largest minimum Euclidean distance is then selected as the optimal mark. Systems and methods are also disclosed for detecting and designing a disk sync mark using correlation detection when the polarity of the disk is unknown or time-varying.
    Type: Grant
    Filed: June 6, 2007
    Date of Patent: July 5, 2011
    Assignee: Marvell International Ltd.
    Inventors: Ke Han, Zining Wu, Michael Madden
  • Patent number: 7965463
    Abstract: Writing data to magnetic tape is performed by receiving data from a host, establishing sub data sets, computing C1 and C2 ECC, forming Codeword Quad sets, writing a beginning Data Set Separator to a magnetic tape, writing a plurality of contiguous instances of the CQ Set to the magnetic tape and writing a closing DSS. The number of instances of each Codeword Pair is increased, thereby allowing the benefits of writing short tape records and improving reading reliability while reducing susceptibility to mis-tracking errors and large defects, and while reducing the negative impact on data reliability. Otherwise unused latency times are utilizing and therefore no performance penalty is incurred.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: June 21, 2011
    Assignee: International Business Machines Corporation
    Inventors: Steven R. Bentley, Paul J. Seger
  • Patent number: 7965462
    Abstract: Methods, logic, apparatus and computer program product write data, comprising less than a full Data Set, to magnetic tape. Data is received from a host, a do-not-interleave command is issued and C1 and C2 ECC are computed. Codeword Quad (CQ) sets are then formed. At least one CQ set of the Data Set is written to a magnetic tape in a non-interleaved manner and a Data Set Information Table (DSIT) is written to the magnetic tape immediately following the at least one written CQ set. An address transformation may be used to cancel interleaving. Writing a CQ set may include writing a plurality of contiguous instances of the CQ set to the magnetic tape to maintain the effectiveness of ECC capability.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: June 21, 2011
    Assignee: International Business Machines Corporation
    Inventors: Masayuki Demura, Glen A. Jaquette, Hisato Matsuo, Keisuke Tanaka
  • Publication number: 20110141602
    Abstract: A method for using magnetic tape having damaged areas is disclosed. The method may include writing data to streaming magnetic tape, determining if the data write was successful, and responding to an unsuccessful data write by interrupting the data writing and advancing the magnetic tape forward a predetermined distance. Additionally, the method may include attempting to write data at the next location on the magnetic tape and determining if the data write was successful. The method may further include repeating the steps of advancing the tape, attempting to write, and determining whether the data write was successful following any determination that an attempted data write was not successful. The method may include further include resuming writing data to streaming magnetic tape at a location where a data write is determined to be successful.
    Type: Application
    Filed: February 24, 2011
    Publication date: June 16, 2011
    Applicant: DELL PRODUCTS L.P.
    Inventors: Perry Joseph Leopold, JR., John H. Dearlove, SR., William Lindsay Theobald, Michael Joseph Linane, III, Dina Eldin
  • Patent number: 7952826
    Abstract: A method of operating a hard disk drive (HDD) on the basis of a predicted new defect in a disk associated with the HDD is disclosed. The method includes detecting defects in a magnetic surface of the disk, defining a plurality of clusters by grouping the detected defects using a hierarchical clustering algorithm, calculating a curve fit for each one of the plurality of clusters, predicting a new defect likely to occur in the magnetic surface of the disk on the basis of the calculated curve fit; and writing data to the disk on the basis of the new defect prediction.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: May 31, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hristov Stoev Youlian, Jin-won Choi, Nam-guk Kim
  • Patent number: 7948699
    Abstract: Various embodiments of the present invention provide data processing circuits that include a multiplexer, a memory buffer, a data processing circuit, and a channel setting modification circuit. A first input of the multiplexer receives an input data set and a second input of the multiplexer receives a buffered data set. The multiplexer provides either the input data set or the buffered data set as a multiplexer output based upon a select signal. The memory buffer receives the multiplexer output and provides the buffered data set. Operation of the data processing circuit is at least in part governed by channel settings. The data processing circuit receives the multiplexer output and performs a data detection process. The select signal is asserted to select the buffered data set when the data detection process fails, and is asserted to select the input data set when the data detection process succeeds.
    Type: Grant
    Filed: January 2, 2009
    Date of Patent: May 24, 2011
    Assignee: LSI Corporation
    Inventors: Jingfeng Liu, Hongwei Song, Richard Rauschmayer, Yuan Xing Lee
  • Patent number: 7945809
    Abstract: A recording medium for storing start position information for each zone, a method of managing data using the information, and an apparatus for recording the information and controlling recording and reproduction of data based on the recorded information. In a disc having a plurality of zones which form a group, and a spare area which is allocated at the start portion or the end portion of the group for replacing defects, when start logical sector numbers of each zone are changed by slipping replacement during initialization or reinitialization, the information is stored in the defect management area to thereby increase the compatibility of the medium. In particular, by the method and apparatus of managing data using information stored in a defect management area, generation of errors is prevented in reading or writing due to the change of a physical position of a real-recorded file which are caused by wrong calculation of the start logical sector numbers for each zone.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: May 17, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jung-wan Ko
  • Patent number: 7936529
    Abstract: A testing apparatus for magnetic recording medium and a testing method for magnetic recording medium is provided. Such a testing apparatus for magnetic recording medium, including: a rotary mechanism which causes synchronous, coaxial rotation of a master medium and a subject medium; a first support arm; a second support arm; a head stack assembly which causes synchronous movement of a first magnetic head and a second magnetic head by causing synchronous, coaxial rotation of the first support arm and second support arm, and which determines the position of the second magnetic head relative to the subject medium based on servo information signals obtained by loading servo information from the master medium into the first magnetic head; and a signal processing mechanism which synchronizes the servo information signals and magnetic recording playback signals, and which tests the magnetic recording playback signals of the subject medium.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: May 3, 2011
    Assignee: Showa Denko K.K.
    Inventor: Junichi Fujita
  • Patent number: 7929233
    Abstract: A system for grading defective bit patterned magnetic media by disk sector in hard disk drives recovers a portion of any defective sectors at a lower areal density. The invention reduces the track pitch density for sectors containing amalgamated islands while leaving the remainder of the defect-free sectors in the zone optimized for linear bit density. This recovers a portion of the defective sector, approximately in proportion to the ratio of amalgamated islands over the original number of islands. A typical zone is first optimized for tracks per inch during formatting of the patterned media disk drive. The zone is then broken up into sectors that can each be optimized separately for linear bit density to ensure the maximum sustainable capacity for each sector.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: April 19, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Christopher W. Bergevin
  • Patent number: 7929234
    Abstract: A disk drive is disclosed comprising a head actuated over a disk, the disk having a plurality of data tracks, wherein a first plurality of data tracks comprises a first plurality of defect scanned data sectors and a second plurality of data tracks comprises a second plurality of unscanned data sectors. The second plurality of data tracks is divided into a plurality of defect zones. A first number of write commands are received from a host to write data to a first defect zone. A first data sector in the first defect zone is defect scanned in response to the first number of write commands to the first defect zone.
    Type: Grant
    Filed: March 27, 2009
    Date of Patent: April 19, 2011
    Assignee: Western Digital Technologies, Inc.
    Inventors: William B. Boyle, Chun Sei Tsai, Anthony L. Pei
  • Patent number: 7929235
    Abstract: Disclosed are a method and system for distinguishing spatial and thermal defects on perpendicular media. The magnetic domains of the perpendicular media are oriented to have a first polarity, scanned using a read head, oriented to have a second polarity and scanned again. The signals from the read head are combined to produce output signals having improved signal to noise ratios from which the locations of spatial and thermal defects can be identified and distinguished.
    Type: Grant
    Filed: May 7, 2009
    Date of Patent: April 19, 2011
    Assignee: MRA TEK, LLC
    Inventors: Stephen Frank Meier, David H. Ferry, Hassan Jalalian
  • Patent number: 7924521
    Abstract: A control module for a rotating storage medium includes a data wedge format table (DWFT). The control module also includes a buffer control module that has a DWFT queue that includes X entries from the DWFT and one of X first servo information for each of the X entries. X is a positive integer. A disk formatter module that compares the one of X first servo information with second servo information that is based on a current position of a read/write device in relation to the rotating storage medium.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: April 12, 2011
    Assignee: Marvell International Ltd.
    Inventors: Lim Hudiono, Daniel R. Pinvidic, Stanley K. Cheong
  • Patent number: 7924522
    Abstract: An apparatus and a method of detecting an error symbol in a data storage apparatus so that an error correcting performance of an error correction decoder.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: April 12, 2011
    Assignee: SAMSUNG Electronics Co., Ltd.
    Inventors: Joo-hyun Lee, Jong-yun Yun, Jae-jin Lee
  • Patent number: 7920350
    Abstract: Data recovery information characterizes data recovery procedure (DRP) steps to be performed within a hard disk drive (HDD) in response to a miss. Particular data recovery information corresponds to a radial position of the actuator and, therefore, the position of the magnetic recording read/write head relative to the associated storage media at the location at which the miss occurred. The data recovery information is based on the physical shape of a write pole and on how the physical shape of the pole inherently affects operational data error associated with the head. Because of the foregoing characteristics of such data recovery information, a more efficient and performant data recovery procedure is performed based thereon.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: April 5, 2011
    Assignee: Hitachi Global Storage Technologies, Netherlands, B.V.
    Inventors: Hoan A. Au, Theofilos G. Fkiaras, David H. Jen, Bernd Lamberts, Kris Schouterden, Douglas M. Zuercher
  • Patent number: 7911725
    Abstract: A hard disk includes: a plurality of servo areas which are elongated radially from a center of the hard disk to an outward thereof over tracks thereof; and a plurality of data areas which are respectively provided between the plurality of servo areas; wherein alternative operation is conducted per servo sector containing one of the plurality of servo areas and a data area provided subsequent to the one of the plurality of servo areas and having a defect created therein when a user sector containing at least a portion of the data area and functioning as an access unit has the defect therein.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: March 22, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenji Yoshida, Yuuichi Abe
  • Patent number: 7904745
    Abstract: A recording medium for storing start position information for each zone, a method of managing data using the information, and an apparatus for recording the information and controlling recording and reproduction of data based on the recorded information. In a disc having a plurality of zones which form a group, and a spare area which is allocated at the start portion or the end portion of the group for replacing defects, when start logical sector numbers of each zone are changed by slipping replacement during initialization or reinitialization, the information is stored in the defect management area to thereby increase the compatibility of the medium. In particular, by the method and apparatus of managing data using information stored in a defect management area, generation of errors is prevented in reading or writing due to the change of a physical position of a real-recorded file which are caused by wrong calculation of the start logical sector numbers for each zone.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: March 8, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jung-wan Ko
  • Patent number: 7903361
    Abstract: In the present invention, an inspection area for sampled defect data is set which has a predetermined width in the radial direction of a magnetic disk and a length round the circle of the magnetic disk in the circumferential direction thereof or a predetermined length in the circumferential direction thereof, and while limiting the defect data in the inspection area and shifting a narrow and long search frame within the area, continuing defects in the region of the search frame are followed up and detected, thereby, only curved line shaped continuing defects having comparatively large curvature near to the circle of the magnetic disk are selectively detected and acquired as circle shaped defects.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: March 8, 2011
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Sumihiro Maeda, Yasuhiro Tokumaru
  • Patent number: 7898758
    Abstract: A method for using magnetic tape having damaged areas is disclosed. The method may include writing data to streaming magnetic tape, determining if the data write was successful, and responding to an unsuccessful data write by interrupting the data writing and advancing the magnetic tape forward a predetermined distance. Additionally, the method may include attempting to write data at the next location on the magnetic tape and determining if the data write was successful. The method may further include repeating the steps of advancing the tape, attempting to write, and determining whether the data write was successful following any determination that an attempted data write was not successful. The method may include further include resuming writing data to streaming magnetic tape at a location where a data write is determined to be successful.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: March 1, 2011
    Assignee: Dell Products L.P.
    Inventors: Perry Joseph Leopold, Jr., John H. Dearlove, Sr., William Lindsay Theobald, Michael Joseph Linane, III, Dina Eldin
  • Patent number: 7898757
    Abstract: A hard disk drive controller includes a buffer block temporarily storing recording data received from a host or reproduced data to be output to the host. A formatter outputs the recording data or the reproduced data and outputs a first control signal and a second control signal based on error information of partial data sectors included in a data sector corresponding to the recording data or the reproduced data. An error correction code block encodes and outputs data corresponding to partial data sectors having no errors in the received recording data based on the first control signal received from the formatter during a write operation and decodes data corresponding to partial data sectors having no errors in the received reproduced data based on the first control signal and outputs the decoded data in response to the second control signal during a read operation.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: March 1, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jae-Chun Park
  • Patent number: 7894150
    Abstract: In one embodiment, a method includes simultaneously writing tracks of data on a magnetic medium in a first direction using less than all available writers in an array of magnetic writers. The method also includes determining that an error has occurred when writing one of the tracks and terminating writing with the writer associated with the track on which the error occurred. In addition, the method includes simultaneously writing tracks of data on the magnetic medium in the first direction using a previously unused writer in the array of magnetic writers.
    Type: Grant
    Filed: April 6, 2009
    Date of Patent: February 22, 2011
    Assignee: International Business Machines Corporation
    Inventors: Robert Glenn Biskeborn, Jason Liang
  • Patent number: 7889449
    Abstract: According to an aspect of an embodiment, a memory device has a medium including a plurality of tracks, each of which has a plurality of sectors separated by a plurality of servo areas, for storing data in the sectors of the tracks, a head for writing data into and reading data from the medium and a controller for determining whether the head has read out data from a sector on a target track correctly or not in reference to information obtained from servo areas sandwiching the sector and for driving the head so as to retry reading out data from the sector when the controller determines that the head failed to have read out data on the target track.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: February 15, 2011
    Assignee: Toshiba Storage Device Corporation
    Inventor: Masami Tashiro
  • Patent number: 7885027
    Abstract: Embodiments of the present invention provide a magnetic disk drive in which the error correction capability of ECC is improved without sacrificing the storage capacity. In one embodiment, a data track adopts a format structure in which no data-to-data gap area is formed in data sectors. When one of the data sectors is updated in a state in which the rotational speed of a magnetic disk does not satisfy specified conditions, a leading end area of a succeeding data sector or a trailing end area of a preceding data sector is overwritten by the data sector. If a read error occurs in the overwritten data sector, ERP steps are executed to perform read retry so that the read error is recovered by means of on-the-fly ECC or erasure correction. In the case of the erasure correction, an erasure pointer equivalent to the maximum number of overwritten bytes is set.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: February 8, 2011
    Assignee: Hitachi Global Storage Technologies, Netherlands, B.V.
    Inventors: Nobuhito Kitamura, Hitoshi Yoshida, Noriyuki Sumiya
  • Patent number: 7885028
    Abstract: A hard disk drive with a disk that has a plurality of data bits. The drive includes a circuit that reads each data bit n times and selects a value for the bit based on the most frequent occurrence of one of a plurality of values. This process provides a voting technique that enhances the quality of accurately captured data.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: February 8, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yawshing Tang, Carl Xiaodong Che, Na-Young Kim
  • Patent number: 7885024
    Abstract: An enhanced oscillation test for detecting off track writing associated with a read/write head writing, on a magnetic media, a measurement track. Once the measurement track is written, a series of seek, write, and read operations is performed, e.g., between various origin tracks and the tracks adjacent to the measurement track, in order to detect any off track write problems. If a measurement track read operation fails a certain number of times, then an error code is generated which indicates an off track write problem.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: February 8, 2011
    Assignee: Hitachi Global Storage Technologies, Netherlands, B.V.
    Inventor: Pirat Boonyurn
  • Patent number: 7880993
    Abstract: The present invention provides a technique for detecting a defect in a tape medium within a relatively short or narrow range. A tape defect detection device includes: a read unit for reading data from a tape medium; an error correction unit for performing error corrections for the data read by the read unit; a correction number counting unit for counting the number of the error corrections, made by the error correction unit, for each of multiple divided areas of the tape medium; a temporary storage unit for temporarily storing, for each of the areas, the number of the error corrections counted by the correction number counting unit; and a detection unit for detecting a defect in the tape medium, on the basis of a distribution of divided areas each having a larger number of error corrections than other divided areas on the tape medium.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: February 1, 2011
    Assignee: International Business Machines Corporation
    Inventors: Setsuko Masuda, Kenji Nakamura, Hirokazu Nakayama, Yutaka Oishi
  • Patent number: 7880994
    Abstract: In a data storage device, a head writes data so as to protect data from off track writing to adjust tracks. A control unit acquires large ring buffer during sequential writing and performs a retry to return adjacent tracks, according to data of a return sector area of the ring buffer when a write error occurs. A write error due to a detection mistake of an off track error can be prevented.
    Type: Grant
    Filed: October 28, 2008
    Date of Patent: February 1, 2011
    Assignee: Toshiba Storage Device Corporation
    Inventor: Noriyuki Sato
  • Patent number: 7880987
    Abstract: Certifying a storage media while servowriting the media by formatting a full compliment of servo data in storage tracks of the media in a minimum number of passes per storage track while simultaneously performing a 100% media certification of the storage tracks during the minimum number of passes per storage track.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: February 1, 2011
    Assignee: Seagate Technology LLC
    Inventors: Ken L. Belmont, Dan R. McLeran, Dave Scott Williamson, Mark Christian Roberts, Gabor Szita
  • Patent number: 7876518
    Abstract: An apparatus is provided that can detect error locations in certify testing of a magnetic recording medium without influence from undulation of the substrate or irregularities in film thickness distribution of magnetic film of the magnetic recording medium. Such an apparatus tests playback signals of a magnetic recording medium, the magnetic head 53 conducts playback of signals which are recorded in the magnetic recording medium. The AGC unit 34 amplifies the played back signals at a gain rate controlled according to elapsed time after input of a signal originating in an error area of the magnetic recording medium among the played back signals. The CMP unit 38 compares the slice level and the level of the amplified signals, and discriminates the existence or non-existence of error.
    Type: Grant
    Filed: February 14, 2008
    Date of Patent: January 25, 2011
    Assignee: Showa Denko K.K.
    Inventors: Shuji Hatada, Junichi Fujita
  • Patent number: 7864890
    Abstract: A signal processing apparatus has a plurality of baseline wander correcting units, provided in a processing path in which a predetermined processing is performed on an input signal. At least one of the plurality of baseline wander correcting units includes a correction permission control unit that controls permission or rejection of correction, and baseline wander in the input signal is corrected sequentially by each of the plurality of baseline wander correcting units, based on a control of the correction permission control unit. The baseline wander correcting unit corrects the baseline wander by determining whether or not the baseline correction is to be effected or not, so that the wander of baseline can be efficiently corrected.
    Type: Grant
    Filed: September 21, 2006
    Date of Patent: January 4, 2011
    Assignee: Rohm Co., Ltd.
    Inventors: Atsushi Esumi, Kai Li, Hidemichi Mizuno
  • Patent number: 7864471
    Abstract: A method includes: writing data to a bit-patterned media at times determined by a clock having a period that is offset from a bit island period by a fixed offset to create one insertion or one deletion approximately within a predetermined number of bit islands, reading the data, and correcting the read data using error correction. An apparatus that implements the method is also provided.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: January 4, 2011
    Assignee: Seagate Technology LLC
    Inventors: Deepak Sridhara, Ching He, Arvind Sridharan, Raman Venkataramani
  • Patent number: 7859784
    Abstract: A data storage device, that stores write data by a head, rewrites data on an adjacent track at a timing which is different from write retry of detecting a head off track when data may be written to an adjacent track. When an off track error, which affects data on an adjacent track, is generated by a write command, rewrite processing of this write command is not executed immediately, but a rewrite request including information on the track to be rewritten and the shift amount of the off track is held. And the rewrite request being held is executed at a timing which is different from the write retry. So rewrite processing can be executed after vibration, which caused the off track, stops, and the generation of an off track error during rewrite processing and the generation of further off track writing can be prevented.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: December 28, 2010
    Assignee: Toshiba Storage Device Corporation
    Inventor: Kenji Ogawa
  • Patent number: 7852596
    Abstract: A disk drive is disclosed comprising a disk and a head actuated over the disk. The disk comprises a plurality of tracks, wherein each track comprises a plurality of data sectors. A read command is received from a host to read data from a target data sector. When it is determined that the target data sector has not been written by the host, dummy data is returned to the host.
    Type: Grant
    Filed: February 25, 2009
    Date of Patent: December 14, 2010
    Assignee: Western Digital Technologies, Inc.
    Inventors: William B. Boyle, Chun Sei Tsai
  • Patent number: 7852586
    Abstract: The invention concerns a method and a device for scanning data stored on a recording medium. The device comprises a reading head and further comprises: means to calculate an error rate of the data read by said reading head, said data being arranged as groups of data, means to align the reading head in respect with the next data to be read according to said error rate of the data read, the reading head reads at least twice some of said groups, changing position in respect with the group of data from one reading to the other, means to compare the calculated error rate corresponding to each position of the said reading head, means to align the reading head with the relative position in respect with the groups of data giving the lowest error rate in order to read the following groups of data, and the means to align the reading head adjust the frequency of the groups of data read at least twice.
    Type: Grant
    Filed: June 12, 2007
    Date of Patent: December 14, 2010
    Assignee: Thomson Licensing
    Inventors: Louis Chevallier, Arnaud Morigault, Lionel Oisel
  • Patent number: 7848041
    Abstract: According to one embodiment, a disk drive that includes a disk and a disk controller is provided which effectively correct data errors that are generated at the time of reproducing data. The disk has a data-recording area constituted by a set of magnetic dots that are physically separated from one another. The disk controller uses error-correcting codes to determine an error that shows a change in the total number of bits in a data-bit string of the data set reproduced.
    Type: Grant
    Filed: April 16, 2008
    Date of Patent: December 7, 2010
    Assignee: Kanushiki Kaisha Toshiba
    Inventor: Akihiko Takeo