Emulating the operation of a video graphics adapter
US7395199B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 2005 |
| Grant date | Jul 1, 2008 |
| Priority date | — |
| Expiry date | Aug 18, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/45541
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for emulating the functionality of VGA hardware, wherein the emulator program of the present invention maintains a set of tables that permits the emulator program to branch to a function customized for both the instruction and the operating mode of the VGA hardware. When the customized function has already been generated, the emulator will automatically dispatch directly into the customized function. If an instruction is executed at a time when the VGA operating mode has changed, the addresses of the customized functions are loaded from a second table. If a customized function is not present, a customized function is generated and the tables are updated to point to the addresses of the newly created customized function. As the VGA hardware is switching among operating modes, a customized function is not generated until such time when an actual instruction is executed for the VGA hardware.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.