File Name Warning and Limitations

  • File names in the controller's flash storage are case-sensitive.
  • The USB flash drive (FAT16or FAT32) are not case-sensitive.

Product

Storage

File System

Case-Sensitive

PCMM2G

Embedded Flash

FFS3 (POSIX-like)

Yes

PCMM2G

USB flash drive

FAT16

FAT32

No

Example

  • Two files (MyFile.txt and myfile.txt) can exist in the same directory of the controller's flash.
    • They cannot exist in the same directory on the controller’s USB flash drive.
  • If you copy two files (via backup operation or function) with the same name but different upper/lower case letters, from the controller's flash to the USB flash drive, one of the files is lost.

  • Use unique file names to prevent conflicts and to keep the application compatible across all platforms.
    Do not rely on case-sensitive file names.

See Also