公开(公告)号：JPH11317027A

公开(公告)日：1999-11-16

申请号：JP3363099

申请日：1999-02-12

Applicant: IBM

Inventor： MARIO BRAUM ,  STEVEN ROBERT HELLER ,  JAQUETTE GLEN ALAN ,  WILLIAM JOHN CABELACK

IPC: G11B20/14 ,  G11B20/12 ,  G11B20/18 ,  H03M7/00 ,  H03M13/00

Abstract: PROBLEM TO BE SOLVED: To make a synchronization recognizable even when an error is occurred in the detecting of a synchronous pattern by allowing an error resistant binary coded mark to include a coded pattern consisting of fixed plural bits and allowing the coded pattern to be at the maximum Hamming distance from the known pattern connected to the number of bits being in the fixed plural bits. SOLUTION: An error resistant binary coded synchronous mark is written as a fixed length coded pattern being at the maximum Hamming distance from the known VFO pattern connected to the number of bits being in the fixed length pattern to be used by a formatter 45 and it is transmitted to a write channel 32. This synchronous mark is also recorded to an opposite direction at the back of coded data and the recorded synchronous mark must become to be at the maximum pattern distance in the opposite direction from the connected known VFO pattern. As a result, a possibility that any part of synchronous patterns is confused with the VFO pattern is low and when an effective synchronous pattern appears in front of the coded data, the synchronization is recognized at a correct position.

公开(公告)号：JPH10320941A

公开(公告)日：1998-12-04

申请号：JP6803598

申请日：1998-03-18

Applicant: IBM

Inventor： MARIO BRAWM ,  STEVEN ROBERT HELLER ,  WILLIAM JOHN CABELACK

IPC: G11B21/10 ,  G11B5/596 ,  G11B7/007 ,  G11B20/12 ,  G11B20/18 ,  G11B21/08

Abstract: PROBLEM TO BE SOLVED: To provide a data storage disk drive with a plurality of servo sectors containing a servo timing mark(STM) that can detect an error and correct it. SOLUTION: Each of STMs 121, 303, and 313 is expressed as a pattern consisting of digital information of n bits, each track has one set consisting of m inherent STM patterns, each of m inherent STM patterns consisting of n bits has the minimum sliding distance (d) for all other STM patterns in the set, and the (d) is larger than 1. In a disk drive, a capability to detect an error can be balanced with a capability to correct the error within a limitation defined by a code. An STM decode circuit can be adapted by updating the comparison value of the error correction and the error detection.

公开(公告)号：JP2000011565A

公开(公告)日：2000-01-14

申请号：JP16616599

申请日：1999-06-14

Applicant: IBM

Inventor： MARIO BROWN ,  WILLIAM JOHN CABELACK ,  LEWIS JOSEPH SERRANO ,  MANTLE MAN-HON YU

IPC: G11B5/596 ,  G11B20/18 ,  G11B21/10

Abstract: PROBLEM TO BE SOLVED: To provide error correcting and detecting method and device for retrieving prescribed data, servo data, for example, from a disk position error signal(PES) field in a data storage device. SOLUTION: In a preferable embodiment, PES data, a truck number, for instance, is mapped into a cord word of an error correcting coding(ECC), the cord word is further divided into one set of symbols, and these symbols are mapped into a second bit/vector group having a specified weight. A preferable encoding method is selected in order to equalize an analog signal characteristic of the PES field. As a result, the change in the conventional servo detector is made to a minimum, even if necessary, as this PES field is used as both of the analog information and digital information.

公开(公告)号：JP2000021105A

公开(公告)日：2000-01-21

申请号：JP16617699

申请日：1999-06-14

Applicant: IBM

Inventor： MARIO BROWN ,  WILLIAM JOHN CABELACK ,  LEWIS JOSEPH SERRANO ,  MANTLE MAN-HON YU

IPC: G11B5/596 ,  G11B5/012 ,  G11B5/82 ,  G11B20/18 ,  G11B21/10 ,  G11B27/30

Abstract: PROBLEM TO BE SOLVED: To provide a disk to be used in a dive drive and a method of manufacturing the same disk. SOLUTION: In the position error signal(PES) field of every track on the disk, encoded predetermined data, for example, servo data is written. In the preferred embodiment, a) data, for example, track number is mapped to the code word of error correcting code(ECC), b) code is encoded for further redundancy using a bit vector and c) unprocessed data written to the PES field is restricted and an analog signal characteristic used by the servo system for positioning is equalized. Therefore, this method enables that PES field can be used as the source of digital data recorded with resistance to trouble while it is used as in the prior art.