Secondary storage facility employing serial communications between drive and controller
US4811279A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 1987 |
| Grant date | Mar 7, 1989 |
| Priority date | — |
| Expiry date | Mar 9, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/0673
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A radial bus for use in a secondary storage subsystem, between a mass storage drive and controller. The bus has four unidirectional bit-serial channels, two for carrying signals from drive to controllers. One channel carries real-time drive state information to the controller; another carries real-time controller state information to the drive. The state information is a sequence of multiplexed bits sent in continuous repetition. Most status variables are represented as a single bit in a specific place in the sequence; the set of status variables defining drive state or controller state, as the case may be, is thus provided by a sequence of bits. When such a bit changes state, a potential change of status has occurred; the change is required to persist some number of repetition of the sequence before the state change is recognized, to avoid spuriously signalling a state change.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.