Method for expanding addressable memory range in real-mode processing to facilitate loading of large programs into high memory
US5642491A · kind A · utility
9Cited by
8References
18Claims
0Family size
Assignee
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Key dates
| Filing date | Sep 21, 1994 |
| Grant date | Jun 24, 1997 |
| Priority date | — |
| Expiry date | Sep 21, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/0292
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Disclosed is a technique for overcoming the 1-Mbyte mode memory limitation associated with "real-mode" operation of certain Intel Corp. microprocessor architectures. This limitation can be overcome by altering the contents of a register portion that is computationally meaningful only in "protected mode," but which persists and exerts effects in real mode. By indirectly manipulating the contents of this register portion in protected mode in a manner that avoids disruption to the register during the switch back to real mode, access can be obtained, in real mode, to up to 4 Gbytes of volatile memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.