Dynamic magnetic information storage or retrieval – General processing of a digital signal – Data clocking
Reexamination Certificate
2005-11-22
2005-11-22
Hudspeth, David (Department: 2651)
Dynamic magnetic information storage or retrieval
General processing of a digital signal
Data clocking
C360S039000
Reexamination Certificate
active
06967799
ABSTRACT:
A disk drive is disclosed servo written from spiral tracks by generating a time-stamped sync mark detect signal processed by timing recovery firmware. A plurality of spiral tracks are written to the disk, wherein each spiral track comprises a high frequency signal interrupted at a predetermined interval by a sync mark. The head internal to the disk drive is used to read the spiral tracks, and a time-stamped sync mark detect signal is generated when one of the sync marks is detected. The time-stamped sync mark detect signal represents a time when the sync mark was detected relative to a servo write clock. A difference between the time-stamped sync mark detect signal and an expected time is computed in firmware to generate a coarse timing recovery measurement used to synchronize the servo write clock. The servo write clock and the head internal to the disk drive are used to write product servo sectors along a substantially circular target path.
REFERENCES:
patent: 5576906 (1996-11-01), Fisher et al.
patent: 5583712 (1996-12-01), Brunelle
patent: 5668679 (1997-09-01), Swearingen et al.
patent: 5696639 (1997-12-01), Spurbeck et al.
patent: 5754352 (1998-05-01), Behrens et al.
patent: 6069499 (2000-05-01), Cho et al.
patent: 6091564 (2000-07-01), Codilian et al.
patent: 6111710 (2000-08-01), Feyh et al.
patent: 6191906 (2001-02-01), Buch
patent: 6249395 (2001-06-01), Conway
patent: 6292318 (2001-09-01), Hayashi
patent: 6304407 (2001-10-01), Baker et al.
patent: 6366225 (2002-04-01), Ozdemir
patent: 6411453 (2002-06-01), Chainer et al.
patent: 6429989 (2002-08-01), Schultz et al.
patent: 6507450 (2003-01-01), Elliott
patent: 6519107 (2003-02-01), Ehrlich et al.
patent: 6587293 (2003-07-01), Ding et al.
patent: 6704156 (2004-03-01), Baker et al.
patent: 6738205 (2004-05-01), Moran et al.
patent: 2004/0003193 (2004-01-01), Chainer et al.
U.S. Appl. No. 09/993,778 entitled “Servo Circuit Having a Synchronous Servo Channel and Method for Synchronously Recovering Servo Data”.
Hudspeth David
Mercedes Dismery
Sheerin, Esq. Howard H.
Western Digital Technologies Inc.
LandOfFree
Servo writing a disk drive from spiral tracks by generating... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Servo writing a disk drive from spiral tracks by generating..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Servo writing a disk drive from spiral tracks by generating... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3510082