In the original version of FAT, files could only carry short “8 dot 3” names, with eight or fewer characters in the main name and three or fewer in its extension. The valid characters in these names are letters, digits, characters with values greater than 0xFF and the following:
$ % ‘ - _ @ ~ ` ! ( ) { } ^ # &
In µC/FS, the name passed by the application is always verified, both for invalid length and invalid characters. If valid, the name is converted to upper case for storage in the directory entry. Accordingly, FAT file names are not case-sensitive.
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