DMA doorbell
US6735642B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2001 |
| Grant date | May 11, 2004 |
| Priority date | — |
| Expiry date | May 18, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2213/2802
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method of direct memory access (DMA) includes receiving a first notification at a DMA engine that a first list of descriptors has been prepared, each of the descriptors in the list including an instruction for execution by the DMA engine and a link to a succeeding one of the descriptors, except for a final descriptor in the list, which has a null link. The DMA engine reads and executes the descriptors in the first list. When the DMA engine receives a second notification that a second list of the descriptors has been prepared, it rereads at least a part of the final descriptor in the first list to determine a changed value of the link, indicating a first descriptor in the second list. It then reads and executes the descriptors in the second list responsive to the changed value of the link.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.