Memory protection system for effecting alteration of protection information without intervention of control program
US4434464A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1981 |
| Grant date | Feb 28, 1984 |
| Priority date | — |
| Expiry date | Mar 31, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1466
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a memory protection system for a computer, memory protection information provided for each of the memory areas of a memory and memory protection information provided for each of the programs executed by a processor are collated to determine allowance/inhibition of access to the memory. By detecting that an instruction to be executed is an instruction having a particular operation and that an address of the memory to be accessed by the instruction is a particular address, the memory protection information for the program executed by the processor is alterd to allow the memory access. The alteration of memory protection information is carried out with no intervention of a control program.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.