基于FPGA和NAND Flash的存储器ECC设计与实现

ECC Design Based on FPGA and NAND Flash Memory

针对以NAND Flash为存储介质的高速大容量固态存储器,在存储功能实现的过程中可能出现的错"位"现象,在存储器的核心控制芯片,即Xilinx公司Virtex-4系列FPGA XC4VLX80中,设计和实现了用于对存储数据进行纠错的ECC算法模块。在数据存入和读出过程中,分别对其进行ECC编码,通过对两次生成的校验码比较,对发生错误的数据位进行定位和纠正,纠错能力为1 bit/4 kB。ECC算法具有纠错能力强、占用资源少、运行速度快等优点。该设计已应用于某星载存储系统中,为存储系统的可靠性提供了保证。

A certain high speed and large capacity storage system is designed using NAND Flash K9WBG08U1M as its storage media.Though NAND Flash is considered to be one of the most reliable storage medium,there is still small probability of single bit error.To detect and correct this error,an Error Correcting Code（ECC） algorithm system is designed and implemented in the Xilinx FPGA XC4VLX80,which is used as the core control chip of the storage system.Through comparing the two ECC codes calculated from the stored data during read and write operation,bit error can be located and corrected,and the correcting capability is 1 bit/4 kB.The ECC algorithm has the advantages of good correcting capability,less resources requirement and high speed.The design has already been applied in a satellite system to ensure the reliability of the storage system.