This implementaion of file system is developed by ELM Chan http://elm-chan.org/fsw/ff/00index_e.html. This is based on FAT file system specification. It provides an interface to physical storage management through its disk io API in diskio.c. The disk io interfaces are updated to interface with Zephyr flash memory management. Current revision in the tree is 0.15 URL to current version: http://elm-chan.org/fsw/ff/arc/ff15.zip