公开(公告)号：JPH09223363A

公开(公告)日：1997-08-26

申请号：JP2905596

申请日：1996-02-16

Applicant: IBM

Inventor： UENO SHINJI ,  IIHARA YASUHIRO ,  ANDO HARUO ,  NAKAMURA TAKASHI

IPC: G11B20/10 ,  G11B20/12 ,  G11B20/18

Abstract: PROBLEM TO BE SOLVED: To efficiently perform data reassigning in a disk device. SOLUTION: In data reassignment processing for moving reading or writing error data in the disk device from an error generation sector position to an alternative region on a disk and recording this, the execution of data reassigning is decided by referring to the remaining capacity of the alternative region in order to efficiently use the alternative region. When the remaining capacity of the alternative region is large, the condition of data reassigning is relaxed and when there is not much remaining capacity, the condition of data reassigning is set strict, only data satisfying a particular condition is moved to the alternative region and for data other than this, only data recovery is performed according to an error recovery procedure(ERP). Thus, the too early disappearance of the alternative region is prevented.

公开(公告)号：JPH087203A

公开(公告)日：1996-01-12

申请号：JP13983794

申请日：1994-06-22

Applicant: IBM

Inventor： SONOBE YOSHIAKI ,  UCHIDA HIROSHI ,  TOYOOKA TAKASHI ,  MATSUI TAKAO ,  AOKI TATSUJI ,  IIHARA YASUHIRO ,  TSUCHIMOTO KAZUNARI ,  OZAWA YUTAKA

IPC: G11B5/39 ,  G11B5/02

Abstract: PURPOSE: To enhance easily the stability of a magnetic domain of a MR head without carrying out complicated works such as disassembling and assembling etc. and reproduce data. CONSTITUTION: A drive device 28 is driven corresponding to a signal output from a controller body 40 of a HDC 30, and it records and reproduces data in a location where an access arm is pivoted at a specific angle. When data for this disk are recorded and reproduced, a bias current supplied to a reproduction element 21A of a magnetic head 20A having a MR effect is turned on/off only for a specific period by a reproduction control circuit 32A. Accordingly, as a direction of a magnetizing vector is changed within a specific period, a magnetic domain of the reproduction element 21A (MR element) is not unstable, but stabilized so that data from the disk can be reproduced stably.