Abstract: Embodiments of the present invention help to reduce the occurrence of read hard errors in a hard disk drive (HDD). According to one embodiment, a HDD rewrites data on all data tracks of a block M when the number of write operations to the block consisting of continuous plural data tracks. The HDD further rewrites data on continuous plural data tracks and adjacent to the block. Since the number of write operations is counted every block, a memory area to register the number of write operations can be reduced.

Abstract: Embodiments of the present invention help to reduce the occurrence of read hard errors in a hard disk drive (HDD). According to one embodiment, a HDD rewrites data on all data tracks of a block M when the number of write operations to the block consisting of continuous plural data tracks. The HDD further rewrites data on continuous plural data tracks and adjacent to the block. Since the number of write operations is counted every block, a memory area to register the number of write operations can be reduced.

Abstract: An automatic replacing method is applicable to a magnetic disc drive used particularly in reading data. When a sign that a unit (sector) at which information is handled may be defective at the time of a reading error is detected (saving threshold), the information in that unit is temporarily stored (saved) in a temporary storage area (backup area). If the unit showing the sign is judged to be definitely defective, the information in that unit is transferred to a safe storage area (replacement area). Thus, fatal reading errors and negligible reading errors can be treated separately.

Abstract: An automatic replacing method is applicable to a magnetic disc drive used particularly in reading data. When a sign that a unit (sector) at which information is handled may be defective at the time of a reading error is detected (saving threshold), the information in that unit is temporarily stored (saved) in a temporary storage area (backup area). If the unit showing the sign is judged to be definitely defective, the information in that unit is transferred to a safe storage area (replacement area). Thus, fatal reading errors and negligible reading errors can be treated separately.

Abstract: An automatic replacing method is applicable to a magnetic disc drive used particularly in reading data. When a sign that a unit (sector) at which information is handled may be defective at the time of a reading error is detected (saving threshold), the information in that unit is temporarily stored (saved) in a temporary storage area (backup area). If the unit showing the sign is judged to be definitely defective, the information in that unit is transferred to a safe storage area (replacement area). Thus, fatal reading errors and negligible reading errors can be treated separately.

Abstract: An automatic replacing method is applicable to a magnetic disc drive (3) used particularly in reading data. When a sign that a unit (sector) at which information is handled may be defective at the time of a reading error is detected (saving threshold ), the information in that unit is temporarily stored (saved) in a temporary storage area (backup area). If the unit showing the sign is judged to be definitely defective, the information in that unit is transferred to a safe storage area (replacement area). Thus, fatal reading errors and negligible reading errors can be treated separately.

Abstract: An automatic replacing method is applicable to a magnetic disc drive used particularly in reading data. When a sign that a unit (sector) at which information is handled may be defective at the time of a reading error is detected (saving threshold), the information in that unit is temporarily stored (saved) in a temporary storage area (backup area). If the unit showing the sign is judged to be definitely defective, the information in that unit is transferred to a safe storage area (replacement area). Thus, fatal reading errors and negligible reading errors can be treated separately.