Here are some notes on the usage of the flash filesystem on the LegoMindstorms NXT controller.
File names can be up to 19 characters long, and are case-insensitive. There is no directory hierarchy; all files are kept in a single top-level directory. The on-board interface shows files grouped into various categories, like “Software files”, “Try Me” etc—these groupings are based purely on the filename extension.
|Datalog files||text files containing sensor data||.log|
|Software files||executable bytecode programs||.rxe|
|Sound files||sound sample files; melody files||.rso|
|Try Me||executable bytecode programs||.rtm|