Specialized PCMCIA host adapter for use with low cost microprocessors
US6665748B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2000 |
| Grant date | Dec 16, 2003 |
| Priority date | — |
| Expiry date | Mar 5, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and method for providing DMA transfers between an adapter card with or with out DMA capabilities and a system CPU with DMA capabilities. An adapter DMA controller circuit resides between the system CPU and the adapter card. This adapter DMA controller allows the system to run in immediate mode which allows the system CPU to talk to the adapter card as if the adapter DMA controller was not there. The system can also run in DMA mode. In this mode the system CPU sets up the system DMA controller and the adapter DMA controller. The adapter DMA controller takes over sending or receiving data to the adapter card and then requesting a DMA transfer with the system DMA controller. The transfer of data between the adapter DMA controller and the adapter does not use any system CPU resources such as the data and address busses. The system CPU is free to use the system resources to continue operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.