FATFS improvements #127
Description
- document internals, @Cheng-Li1 wrote some documentation, need to find the best place for it. Attached is the docs.
- currently the implementation does not efficiently make use of the sDDF block interface. Each worker cothread will only make a single block request at any given time. This means the asynchronous interface of sDDF is used in a synchronous way, meaning that performance is not going to be great.
- fixup grammar of comments