Method and system for device virtualization based on an interrupt request in a dos-based environment
US5790837A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 1996 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Sep 11, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2009/45579
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A technique for providing device virtualization in an MS-DOS based operating environment, using an interrupt request (e.g., a non-maskable interrupt), is described. The technique includes executing an application on a processor within the MS-DOS based operating environment and, when the application attempts to address the device to be emulated, causing a processor interrupt to occur. In response to the interrupt, the processor executes code representing the virtualization of a device. The code for servicing the interrupt and emulating the device are written in protected-mode code, stored in the extended memory area, and made available by making appropriate entries into the interrupt descriptor tables (IDTs) for the protected-mode contexts which exist for the native protected-mode operating systems and for the DOS extender. The entries made into the IDT for the protected-mode context established for the DOS extender are accomplished by intercepting communications between the DOS extender and the virtual control program interface (VCPI).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.