File Name Warning and Limitations

• File names in the controller's flash storage are case-sensitive.
• The SD card or USB "Universal Serial Bus" USB is a serial bus standard to interface devices flash drive (FAT16 or FAT32) are not case-sensitive.

Storage	File System	Case-Sensitive
Embedded Flash: AKD PDMM / PCMM / PCMM2G	FFS3 (POSIX-like)	Yes
SD card / USB flash drive: AKD PDMM / PCMM	FAT16 or 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 SD card.
• 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 SD card or 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

• SD Card Path Conventions
• Shared Directory Path Conventions
• USB Flash Drive Path Conventions