# US 2020/0081779 A1 · Magnetic disk device and data read method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0081779 A1 - Document ID: US20200081779A1 - Status: Published application - Kind: A1 - Application number: 16/291,756 - Filed: 2019-03-04 - Published: 2020-03-12 - Earliest claimed: 2018-09-06 - Assignees: Toshiba Electronic Devices & Storage Corporation; Kabushiki Kaisha Toshiba - Applicants: Toshiba Electronic Devices & Storage Corporation; Kabushiki Kaisha Toshiba - Inventors: Yosuke KONDO - Web page: https://patentgrep.com/patent/US20200081779A1 ## CPC - G06F 11/1076: {Parity data used in redundant arrays of independent storages, e.g. in RAID systems} - G11B 20/1889: {with discs} - G06F 11/1044: {with specific ECC/EDC distribution} - H03M 13/1148: {Structural properties of the code parity-check or generator matrix} - H03M 13/25: Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM] {(modulation codes H03M13/31)} - H03M 13/6312: {Error control coding in combination with data compression} - G11B 2020/1896: {using skip or slip replacement to relocate data from a defective block to the next usable block, e.g. with a primary defect list [PDL]} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A magnetic disk device includes a magnetic disk, which includes, in a track, a plurality of first sectors each recording user data and a second sector recording parity data for restoring the user data recorded in the first sectors, and a disk controller configured to read data from a plurality of sectors including the first sectors and the second sector based on an instruction from a host, and to detect whether there is an error in each of the first sectors when the user data is read from the first sectors. The disk controller continues reading the data recorded in the plurality of sectors even when an error is detected in one of the first sectors by the disk controller. ## Claims ### Claim 1 A magnetic disk device, comprising: a magnetic disk which includes, in a track, a plurality of first sectors each recording user data and a second sector recording parity data for restoring the user data recorded in the first sectors; and a disk controller configured to read data from a plurality of sectors including the first sectors and the second sector based on an instruction from a host, and to detect whether there is an error in each of the first sectors when the user data is read from the first sectors, wherein the disk controller continues reading the data recorded in the plurality of sectors even when an error is detected in one of the first sectors by the disk controller. ### Claim 2 (depends on 1) The magnetic disk device according to claim 1, wherein the disk controller is configured to perform error correction processing on data read from each of the sectors, and the error that the disk controller is configured to detect includes a first error indicating that error correction processing performed on the data read is not successful and a second error indicating that the sector from which the data is read is an error sector. ### Claim 3 (depends on 2) The magnetic disk device according to claim 2, wherein when the first error is detected by the disk controller during reading of the user data recorded in the first sectors, the disk controller continues reading of the data recorded in the plurality of sectors until the parity data is read from the second sector. ### Claim 4 (depends on 3) The magnetic disk device according to claim 3, wherein the disk controller is further configured to: restore user data in the first sector detected to have the first error using the parity data. ### Claim 5 (depends on 3) The magnetic disk device according to claim 3, wherein when the first error is detected by the disk controller during reading of the user data recorded in one of the first sectors and the second error is detected by the disk controller during reading of the user data recorded in another one of the first sectors, the disk controller interrupts the reading if the first sector detected to have the second error is read earlier than the first sector detected to have the first error. ### Claim 6 (depends on 5) The magnetic disk device according to claim 5, wherein the disk controller is configured to determine that the first sector detected to have the second error is read earlier than the first sector detected to have the first error when results of error correction processing have been returned from each the first sectors that were read earlier than the first sector detected to have the second error. ### Claim 7 (depends on 3) The magnetic disk device according to claim 3, wherein when the first error is detected by the disk controller during reading of the user data recorded in one of the first sectors and the second error is detected by the disk controller during reading of the user data recorded in another one of the first sectors, the disk controller continues reading of the data recorded in the plurality of sectors until the parity data is read from the second sector if the first sector detected to have the first error is read earlier than the first sector detected to have the second error. ### Claim 8 (depends on 1) The magnetic disk device according to claim 1, wherein the data are recorded in the magnetic disk by a shingled magnetic recording technique. ### Claim 9 A method for reading data in a magnetic disk device including a magnetic disk which includes, in a track, a plurality of first sectors each recording user data and a second sector recording parity data for restoring the user data recorded in the first sectors, the method comprising: reading data from a plurality of sectors including the first sectors and the second sector based on an instruction from a host; and detecting whether there is an error in each of the first sectors when the user data is read from the first sectors, wherein the reading of the data in the plurality of sectors is continued even when an error is detected in one of the first sectors. ### Claim 10 (depends on 9) The method according to claim 9, further comprising: performing error correction processing on data read from each of the sectors, wherein the error that is detected includes a first error indicating that error correction processing performed on the data read is not successful and a second error indicating that the sector from which the data is read is an error sector. ### Claim 11 (depends on 10) The method according to claim 10, wherein when the first error is detected during reading of the user data recorded in the first sectors, reading of the data recorded in the plurality of sectors is continued until the parity data is read from the second sector. ### Claim 12 (depends on 11) The method according to claim 11, further comprising: restoring user data in the first sector detected to have the first error using the parity data. ### Claim 13 (depends on 11) The method according to claim 11, further comprising: when the first error is detected during reading of the user data recorded in one of the first sectors and the second error is detected during reading of the user data recorded in another one of the first sectors, interrupting the reading if the first sector detected to have the second error is read earlier than the first sector detected to have the first error. ### Claim 14 (depends on 13) The method according to claim 13, further comprising: determining that the first sector detected to have the second error is read earlier than the first sector detected to have the first error when results of error correction processing have been returned from each the first sectors that were read earlier than the first sector detected to have the second error. ### Claim 15 (depends on 11) The method according to claim 11, wherein when the first error is detected by the disk controller during reading of the user data recorded in one of the first sectors and the second error is detected by the disk controller during reading of the user data recorded in another one of the first sectors, reading of the data recorded in the plurality of sectors is continued until the parity data is read from the second sector if the first sector detected to have the first error is read earlier than the first sector detected to have the second error. ### Claim 16 (depends on 9) The method according to claim 9, wherein the data are recorded in the magnetic disk by a shingled magnetic recording technique.