Compression of data in read only storage and embedded systems
US6349375B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1999 |
| Grant date | Feb 19, 2002 |
| Priority date | — |
| Expiry date | May 10, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/401
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
This disclosure involves the combination of data compression and decompression with a virtual memory system. A number of computer systems are discussed, including so-called embedded systems, in which data is stored in a storage device in a compressed format. In response to a request for data by a central processing unit (CPU), the virtual memory system will first determine if the requested data is present in the portion of main memory that is accessible to the CPU, which also happens to be where decompressed data is stored. If the requested data is not present in the decompressed portion of main memory, but rather is present in a compressed format in the storage device, the data will be transferred into the decompressed portion of main memory through a demand paging operation. During the demand paging operation, the compressed data will be decompressed. Likewise, if data is paged out of the decompressed portion of main memory, and that data must be saved, it can also be compressed before storage in the storage device for compressed data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.