Mechanism allowing asynchronous access to graphics adapter frame buffer physical memory linear aperture in a multi-tasking environment
US6510470B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 18, 1998 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Dec 18, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/393
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A module is interposed between a multitasking operating system and the device driver for a graphics adapter including a frame buffer with a linear aperture for continuous, asynchronous data transfers. The interposed module may selectively intercept all graphics device driver function requests or simply pass such requests to the device driver, and provides a mechanism for generating graphics output in the frame buffer without utilizing graphics accelerator hardware on the graphics adapter. The interposed module is aware of the start and stop of asynchronous data transfers to the frame buffer. When asynchronous data transfers are started, the interposed module invokes the graphics adapter device driver to obtain access to the frame buffer linear aperture and sets its own internal state to active. While active, the interposed module intercepts all graphics device driver requests and employs its own mechanism to generate graphics output in the frame buffer responsive to such requests, without utilizing the graphics accelerator hardware. Since the graphics accelerator hardware is not utilized, the frame buffer linear aperture always remains enabled. While inactive, the interposed module…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.