Header verification in a disk drive using sector histories for improved format efficiency
US5568627A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | Apr 5, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique for verifying a pre-recorded header in a disk drive uses verification history to protect against errors that can cause verification failure. A head number, sector address, and upper track address (track MSB) are read from the disk and compared with corresponding expected values. The results of the 5 most recent comparisons are saved in three 5-bit memories. During each verification, a programmable selection and comparison circuit selects M of the stored indicators and determines whether at least N of them indicate a match. If so, the corresponding field is declared to be correctly verified, so that subsequent reads or writes to data blocks within the corresponding sector are allowed to proceed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.