I was wrong about the file format. I ran this command `# fsck -N /dev/mmcblk0p1` to check the format, and it outputted this:
`[/run/current-system/sw/bin/fsck.ext2 (1) -- /dev/mmcblk0p1] fsck.ext2 /dev/mmcblk0p1`
Later I found out that this wasn't true, and that the actual filesystem was vfat as Hermann had suggested. Mounting with this command fixed the issue:
`# mount -t vfat /dev/mmcblk0p1 /path/to/mnt -o shortname=mixed -o utf8`
> The “shortname=mixed” keeps the case preserved, as otherwise vfat will convert any filename that’s 8 characters or less to lower case (default behavior is “shortname=lowercase”) and cause problems for rsync. UTF8 is what Windows uses when mounting filesystems, so we specify that to ensure that we’re mounting it the same way (default is to mount iso-8859-1, even though the underlying vfat filesystem will store filenames in UTF8 format).
I found the command on this site: <