Use of erasable non-volatile memory for storage of changing information
US6104638A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1999 |
| Grant date | Aug 15, 2000 |
| Priority date | — |
| Expiry date | Feb 26, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/102
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Non-volatile write-once memory, is used for storage of variable data. In an example embodiment, segmented flash memory is used, in which individual segments can be erased. At least two segments are used. When a segment is nearly full, or when the segment is corrupted, the latest values are written to a new segment. During initialization, all variables of interest are written into RAM with default values. The flash segment being used is read sequentially from oldest entry to newest entry, and values from flash memory are used to overwrite values (or pointers to values) in RAM. RAM then contains (or points to) the most recent value for every variable. When a new segment is written, the new segment is written using the values from RAM. The method provides for identification of the latest (current) value for each stored item of information, provides for adding new types of data and deleting old types of data, provides for action when a memory segment is full, and provides for recovery from power-failure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.