sfyip

The FAT32 write procedure is handled at fat32_write(). I only tested on macOS Sierra. I will update my macOS to big sur to check it out.

Do not find any problem if using macOS Big Sur. Which macOS version are you using? I can't test on MacOS Ventura because my Mac book Air is not compatible....

Tested STM32F103_FlashPC13LED_FAST_CRYPT.hex. It also works on my Mac book Air (macOS Big Sur and Monterey).

The minimum FAT32 disk size is 32MB, it cannot indicate 64KB flash capacity.

http://elm-chan.org/fsw/ff/doc/getfree.html Usually looks into the free cluster size in FAT32 structure.