Hi all, When I started compiling and linking the ARTX flash file system I get some errors from the linker. (L25: DATA TYPES DIFFERENT / SYMBOL: _iob). The solution is very simple, it is possible to choose if char default signed or unsigned (options, tap 'C', treat plain char as 'unsigned char' must be checked). I hope that this will be the solution what you need… (For KEIL, maybe it is for the future better to use unsigned and signed by the declaration for the lib files).