Data storage method and system for NandFlash

Abstract

The invention discloses a data storage method for NandFlash, which comprises the following steps of: collecting a write data page number corresponding to data which needs to be written at present, and the write data page number is obtained by adding one to a page number recorded before the end of a previous write cycle; reading and recognizing the state of the current page number from a preset page state table; if the page is a good page, writing the to-be-written data into the current page, performing data reading verification, marking the current page in the page state table as a bad page when the verification is wrong, generating a new page number of the current page so as to perform state recognition from the page state table, and recording a write data page number of a current write cycle when the verification is correct, and entering the next writing cycle. According to the invention, the space utilization rate and the service life of the device are improved, correct writing of data in each period is ensured, and the continuity of stored data is ensured.

Description

technical field [0001] The invention relates to the field of storage technology, in particular to a data storage method and system for NandFlash. Background technique [0002] Because the manufacturing process and storage principle of NAND FLASH devices determine that bad blocks will inevitably be generated during the production process and use process, therefore, bad block management is a necessary strategy in NAND application scenarios. On the one hand, bad blocks need to be identified and marked when the chip leaves the factory; at the same time, bad blocks generated during use must also be isolated, otherwise continued use will lead to the risk of potential data loss. [0003] Since NAND FLASH includes multiple blocks, and each block includes multiple pages. Wherein, the block structure is the minimum operation unit in the erasing process, and the page structure is the minimum operation unit in the data writing process. In the prior art, the common practice is to judge...

AI Technical Summary

Problems solved by technology

In the prior art, the common practice is to judge whether the block is a bad block based on the block as a whole. As long as there is an uncorrectable bit in a page in the whole block, the block is judged to be a bad block, and all pages of the block are cannot continue to use

Therefore, in order to ensure the continuity of the stored data, it is necessary to move the data of the good pages in the existing bad block to the new block, but in fact, the storage units of other pages in the block are still normal, and the data can still be stored normally Therefore, the existing data storage bad block management method has a large waste and a large space loss, and also reduces the service life of the NAND FLASH device. At the same time, it takes a long time to move data, which affects the storage of new data. Not conducive to the continuity of data storage

[0004] In addition, although some data storage bad block management methods involved in the prior art can mark bad blocks in units of pages, so as to effectively improve the space utilization rate and service life of NAND FLASH devices, they cannot address the problems involving repeated Real-time bad page marking is carried out during the use of erasing and writing operations. It is still about the bad block recovery scheme at the factory. Bad blocks caused by continuous repeated reading and writing during data storage cannot be marked, and bad pages are encountered during data writing. block continuity cannot be guaranteed

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