基于地址映射的NAND Flash控制器设计

Design of NAND Flash Controller Based on Address Mapping

摘要:

针对嵌入式数据采集系统对NAND Flash进行读写控制时出现的坏块问题和磨损失衡问题，对数据采集系统的工作特点进行分析，借鉴闪存转换层的思想，提出了一种基于地址映射的NAND Flash控制方法，通过建立、维护、查询NAND Flash存储块逻辑地址与物理地址之间的映射关系表，实现NAND Flash的坏块管理和磨损均衡功能，同时介绍了使用地址映射方法的NAND Flash控制器设计过程；仿真测试和实际应用结果表明，基于地址映射方法设计的NAND Flash控制器能够识别、管理出厂坏块和突发坏块，均衡存储块的磨损，提高嵌入式数据采集系统的可靠性；该方法实现过程简单，无需移植文件系统，硬件资源要求低，为嵌入式数据采集系统中NAND Flash的读写控制提供了新的思路。

Abstract:

Aiming at problems of bad blocks and uneven wear when using NAND Flash in embedded data acquisition system, a NAND Flash control method based on address mapping is proposed by analyzing the working characteristics of data acquisition system and using the idea of Flash translation layer. The method implements functions of bad block management and wear-leveling through establishing, maintaining and querying the address mapping table about logical to physical addresses conversion of NAND Flash blocks. The design of NAND Flash controller using the way of address mapping is introduced. The results of simulation and application show that the NAND Flash controller based on address mapping could identify and manage bad blocks original and burst, level wear of blocks and improve reliability of system. The method is simple to implement, could work without migrating file system and has low hardware requirements, which provides a new idea for NAND Flash control in field of embedded data acquisition system.