Using prioritized interrupt callback routines to process different types of multimedia information
US5940610A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 3, 1996 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Oct 3, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/426
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Multimedia information (e.g. graphics, video, sound, control information) passes through a system bus from a CPU main memory to a display memory in accordance with CPU commands. The information may be packetized with associated packet types identifying the different media. A media stream controller processes the information and passes the processed information to the display memory. Controllers in the media stream controller individually pass multimedia information to the display memory. A PACDAC controller in the media stream controller causes media (e.g. graphics, video) in the display memory to be transferred to a PACDAC for display. The format, sequence, and rate of this transfer may be flexibly controlled by software on a frame by frame basis. Arbitration logic establishes priorities for the different controllers in the media stream controller so they may share a single bus for accessing the display memory. A single interrupt controller coordinates interrupts (e.g. at a single level) to provide priorities based upon the type of interrupt cause or media. Each interrupt cause activates only the appropriate callback functions. Two different virtual machine sessions (e.g. Windows,…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.