Abstract: In a digital system having a host, a controller device and at least one nonvolatile memory integrated circuit, such as a flash memory chip, a method and apparatus is disclosed for storing digital information, provided by the host, in the nonvolatile memory under the direction of the controller in an efficient manner so as to significantly improve system performance. The nonvolatile memory is organized into sequentially-numbered blocks. Each nonvolatile integrated circuit is assigned a predetermined number of sequential blocks and when a free block is solicited for storage of digital information provided by the host, the nonvolatile integrated circuit rather than the entire nonvolatile memory is searched for the free block. When the information stored in a block is being updated by the host, the nonvolatile integrated circuit assigned to that block is excluded from the search for the free block.

Abstract: A method and apparatus is disclosed for increasing the system performance of a digital system having a controller for controlling nonvolatile devices for storing blocks of information, each block having a group of sectors. When sectors within a block are being re-written in sequential order, the controller writes the new sector information into a sector location of another block without the need to move any of the sectors within the original block thereby reducing the number of read and write cycles needed to avoid erase-before-write operations. A `used` flag, stored in the sector location of each block, indicates that the sector has been transferred to another block or, alternatively, a move locator word maintains status information regarding the position of the sectors within the block that have been moved.

Abstract: In a digital system having non-volatile memory devices for storage of digital information therein, the digital information being organized in sectors, each sector having a data field and a corresponding extension field, a controller device for performing operations such as reading and writing to and erasing information from a selected plurality of sectors and further verifying successful erasure of the selected erased sectors, the controller device including an error detection circuit for detecting errors within each of the sector data fields using the corresponding sector extension field and a flash interface circuit coupled to the non-volatile devices through a data bus for receiving an erased sector of information therethrough and being operative to pass the data field of the erased sector information and a predetermined extension field to the error detection circuit wherein the error detection circuit calculates an extension field corresponding to the erased sector data field, compares the calculated exte

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.

Abstract: A device is disclosed for storing mapping information for mapping a logical block address identifying a block being accessed by a host to a physical block address, identifying a free area of nonvolatile memory, the block being selectively erasable and having one or more sectors that may be individually moved. The mapping information including a virtual physical block address for identifying an "original" location, within the nonvolatile memory, wherein a block is stored and a moved virtual physical block address for identifying a "moved" location, within the nonvolatile memory, wherein one or more sectors of the stored block are moved. The mapping information further including status information for use of the "original" physical block address and the "moved" physical block address and for providing information regarding "moved" sectors within the block being accessed.

Abstract: A semiconductor non-volatile mass storage memory is partitioned into user files and system files. The system files partition is further subdivided into clusters, each cluster having a plurality of sectors. Each cluster stores the system file for a single predetermined LBA. As the information within the LBA is changed, the new information is written into an empty sector within the cluster. Once the cluster is filled, the system either erases for recycling the cluster or preferably locates an empty cluster and repeats the process with that new cluster. Once all the clusters are filled, all clusters containing old data are erased for recycling.