Browse Prior Art Database

Hard Disk Drive having Data Address Mark

IP.com Disclosure Number: IPCOM000111964D
Original Publication Date: 1994-Apr-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Kigami, Y: AUTHOR [+3]

Abstract

Disclosed is a highly reliable small Hard Disk having NO ID format with high track density. By writing the different DAMs (Data Address Marks) for the even tracks from the DAMs for the odd tracks, any misreading of the track, such as reading of the adjacent track's sector as the target sector, is completely prevented.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 88% of the total text.

Hard Disk Drive having Data Address Mark

      Disclosed is a highly reliable small Hard Disk having NO ID
format with high track density.  By writing the different DAMs (Data
Address Marks) for the even tracks from the DAMs for the odd tracks,
any misreading of the track, such as reading of the adjacent track's
sector as the target sector, is completely prevented.

      In conventional small Hard Disk Drives, DATA fields are placed
just after ID fields which include sector identifications, such as
logical block addresses, defective sector flags, etc.  Before
read/write operations, the ID field is verified to ensure that the
DATA field coming to the position of the head is the target sector or
not.  But in the case of the HDD having NO ID format, the sector is
identified only by the physical location of the track and sector
(Fig. 1).

      The information on the physical location of the head is
acquired from the servo pattern in HDD.  But in the case of a sudden
shock, the head sometimes flies to an off-track position and makes a
miswrite and a misread.  Conventionally, some fail-safe operations
are adopted for avoiding the erroneous write operation.  But these
fail-safe operations worsen the performance of the operation.

      The subject invention provides a HDD having DAMs which are
written on the tracks for providing the information as to whether the
data track is an odd track or an even track.  By reading the DAM, it
is possible to identify wh...