I'm trying to connect Keil FAT File System and NAND flash NAND512W3A2CN6E on our board(MCU is STM32F207VET6, NAND flash connected to FSMC bank 2). I used Keil File System Demo example as starting point for my project in uVision v5.15. I modified all required settings and when in debug mode I'm trying to format NAND flash with fformat("N0:","/LLEB") function, it return error result 8 == fsDriverError. Call to finit ("N0:") return result fsOK, and call to fmount ("N0:") return result such as fsNoFileSystem. As I don't have sources for FAT file system, I can't understand what's wrong with my project, may be some others settings must be corrected or something else. I don't have any ideas more. Can anyone help me?