Method and apparatus for maintaining variable data in a non-volatile electronic memory device
US5386533A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1990 |
| Grant date | Jan 31, 1995 |
| Priority date | — |
| Expiry date | Nov 21, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C22/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for maintaining variable data in a non-volatile electronic memory device comprises a shifter array (106) which provides a shifter value to shifter register (104). Shifter register (104) uses 8-bit column decoder (110) to specify which of a plurality of overlapping storage units in array (94) will store variable data provided from register (92). Address register (112) specifies to row decoder (116) which of two rows in shifter array (106), pointer array (118) and array (94) will be accessed by read and write operations. Pointer array (118) stores an index specifying which of the two rows contains the most recently updated variable data. Shifter register (104) uses 8-bit column decoder (108) to specify which of a plurality of adjacent storage units in pointer array (118) will store the index. OR gate (98) specifies when to replace an overlapping storage unit in array (94) and an adjacent storage unit in pointer array (118).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.