Computer system employing optimized delayed transaction arbitration technique
US6199131A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1997 |
| Grant date | Mar 6, 2001 |
| Priority date | — |
| Expiry date | Dec 22, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/4031
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A computer system includes a bus bridge which provides an interface between a main memory and a peripheral bus such as a PCI bus. A peripheral bus interface unit is provided which supports delayed transactions. When a PCI bus master effectuates a read cycle to read data from main memory on the PCI bus, the peripheral bus interface detects the read cycle and terminates or retries the transaction on the PCI bus. The peripheral bus interface further requests the read data from main memory and places the read data in a buffer. When the PCI master device re-attempts the read transaction, the peripheral interface provides the read data directly from its delayed read buffer. When the peripheral bus interface retries the PCI master that establishes a delayed read operation, the peripheral bus interface asserts a control signal referred to the delayed cycle signal. A PCI arbiter which controls ownership of the PCI bus receives the delayed cycle signal and, in response to its assertion, lowers a level of arbitration priority provided to the PCI master establishing the delayed read. In one embodiment, the PCI arbiter inhibits ownership of the PCI bus by the master establishing the delayed rea…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.