Implementation of a Reed-Solomon Code as an ECC in Yet Another Flash File System

Flash memory has become an important storage device in many embedded systems because of its high performance, low power consumption and shock resistance. Multi-level cell (MLC) is developed as an effective solution for reducing the cost and increasing the storage density in recent years. However, most of flash file system cannot handle the error correction sufficiently. To correct more errors for MLC, we implement Reed-Solomon (RS) code to YAFFS, what is widely used for flash-based file system. RS code has longer computing time but the correcting ability is much higher than that of Hamming code.

Authors:

• Sungjoon Sim
• Soongyu Kwon
• Dongjae Song
• Jong Tae Kim

Keywords:

• Reed-Solomon
• NAND flash memory
• YAFFS
• ErrorCorrecting Code
• Flash File System

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