Fault tolerant servo address mark for disk drive
US5544135A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1994 |
| Grant date | Aug 6, 1996 |
| Priority date | — |
| Expiry date | Oct 11, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59616
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and method for detecting occurrence of a non-pulse interval of predetermined length between a beginning pulse and an ending pulse as included within a sequence comprising a unique timing mark within a stream of pulses supplied from a source with a state machine. The method of the state machine includes the the steps of: PA1 advancing through a plurality of nominal states marking in time the non-pulse interval, PA1 branching to one of a plurality of available spurious pulse states from one of the nominal states upon detection of a first unexpected pulse, PA1 returning to advance through predetermined remaining ones of the plurality of nominal states following detection of the first unexpected pulse, PA1 reaching a completion state following the nominal states if only the first unexpected pulse is detected, and PA1 reaching an error state following a branch to another one of the plurality of available spurious pulse states upon detection of a second unexpected pulse within the non-pulse interval.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.