Apparatus and method for record reorientation following error detection in a data storage subsystem
US4209809A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 1978 |
| Grant date | Jun 24, 1980 |
| Priority date | — |
| Expiry date | Sep 11, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59655
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an apparatus and method for record reorientation following error detection in a data storage subsystem each data track is subdivided into equal time-length recording cells which are sequentially numbered past an index point with the beginning of each field of each record coinciding with an initial cell for the field. Upon detection of a retriable error within a given field, the initial cell for the field is determined and stored, the subsystem is disconnected from an interfacing channel, and reorientation is attempted by advancing a transducer addressing the track past the index point to a location which is a selected distance upstream of the stored cell number. If a selected channel command is then received within a given time interval, the subsystem is reconnected to the channel and reorientation is effected as the transducer enters the field the initial cell of which was stored. If the selected channel command is received late, the subsystem waits one revolution of the track and then reorients without looking for further channel commands.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.