The Research Of NAND Flash Memory-based Embedded File System

With the development and application of computer technology, the use of embedded systems is becoming increasingly commonplace. NAND Flash is a kind of flash memory, it is widely used in embedded systems for its practical features. Embedded systems often need file system to manage the NAND Flash, most of the current popular file system are high specially, do not have good compatibility, but mainstream desktop operating systems support FAT file system.Designed and implemented a embedded file system named WLFAT for applications based on NAND flash memory, WLFAT is based on FAT file system, with the same compatibility and add flash translation layer to implement the management of the underlying storage media based on NAND Flash hardware features, such as address mapping, bad block management. Specifically:(1) describes the principles of FLASH memory, hardware features, classification and comparative for 2 main flash. Introduces the basics of file systems, functions and major operations, analysis of the composition of the embedded file system and system requirements, and the current mainstream of the embedded file system.(2) a detailed description of the basic principles of FAT file system, then depict the overall design, and describes the implementation details by modules.(3) study the problems encountered in NAND flash management, then leads to FTL concept and propose the design of this FTL. Made in the overall framework and then detail implementation mechanisms.In this paper, the practical and compatibility are take into account, on one hand consider the hardware characteristics of NAND FLASH fully, design targeted management mechanism, on the other hand taking into account the NAND FLASH memory devices for the embedded systems often need and desktop operating system exchange data, design inherited the FAT file system compatibility.