Access-arbitration scheme
US4641266A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 1983 |
| Grant date | Feb 3, 1987 |
| Priority date | — |
| Expiry date | Nov 28, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/37
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a processing system (10) that utilizes daisy-chain arbitration for controlling access to a shared resource (11,13) by a plurality of using devices (1-4,12), a using device (1-4) is allowed to issue an access request signal onto a request signal line (17) shared in common with the other using devices (1-4) only when it senses that the request line is idle. Sensing is done during one clock period and issuance of the request signal is done during the next clock period. The clock period exceeds the signal propagation delay across the request line. Receipt by the arbitrator (14) of a request signal is delayed by a clock period. Access grant signals are daisy-chained by a grant line (18) between the using devices (1-4), without synchronization at each device of issuance of the request signal and receipt of the grant signal, and without multiple sampling at each device of the grant signal. Following receipt of a grant signal, a using device ceases to issue its request signal only upon detecting the end of the grant signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.