Method for automatically transitioning from V86 mode to protected mode in a computer system using an Intel 80386 or 80486 processor
US5255379A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 28, 1990 |
| Grant date | Oct 19, 1993 |
| Priority date | — |
| Expiry date | Dec 28, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/461
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for transitioning an Intel processor from virtual 8086 (V86) mode to protected mode operation which detects when a virtual V86 processor attempts to transition to protected mode, stores all of the information concerning the virtual processor at the time of the attempt to transition to protected mode, remaps the memory allotted to the virtual processor to the memory space used in running a process in real mode, sets up a dummy stack to provide for operation during a transition to protected mode, moves a process for transitioning to real memory space, shifts all of the register values to values for real memory space, and finally reactivates the transition to protected mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.