Computer system having software interrupt (INTN) instructions selectively operating in a virtual mode
Abstract
Abstract A computer system is disclosed herein including a given microprocessor specifically designed to operate in a virtual operating mode that allows a software program previously written for an earlier designed single program microprocessor to execute in a protected, paged, multi-tasking environment under a particularly designed host operating software program. The system also includes means for executing software interrupt (INTn) instructions, using emulation software forming part of the host program in order to emulate the way in which these instructions would have been executed by the earlier microprocessor. As a unique improvement to this overall computer system, certain ones of the INTn instructions are executed by means of emulation software while others are executed by means of the previously written program in cooperation with the given microprocessor and its host operating software program.
Inventors
- 👤 John H. Crawford
- 👤 Donald Alpert
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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