Direct logical block addressing flash memory mass storage architecture
US5924113A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1998 |
| Grant date | Jul 13, 1999 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/1068
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A nonvolatile semiconductor mass storage system and architecture can be substituted for a rotating hard disk. The system and architecture avoid an erase cycle each time information stored in the mass storage is changed. Erase cycles are avoided by programming an altered data file into an empty mass storage block rather than over itself as a hard disk would. Periodically the mass storage will need to be cleaned up. These advantages are achieved through the use of several flag, and a map to correlate a logical block address of a block to a physical address of that block. In particular, flags are provided for defective blocks, used blocks, and old versions of a block. An array of volatile memory is addressable according to the logical address and stores the physical address. Furthermore, the volatile memory device is configured to store physical block addresses in volatile memory locations identified by logical block addresses and is configured to store flags in volatile memory locations identified by the physical block addresses. During power-up the physical block addresses are used to address the volatile memory locations and update the flags with shadow flags of the nonvolatile mem…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.