FatFs is an open source library used in many embedded devices to interface with FAT file systems in Block devices such as SD cards, flash drives, etc. It can load a FAT or ExFAT filesystem found inside a partition in an MBR partition table. However, it doesn’t provide support to find a FAT filesystem inside a GUID partition table.
This blog post will provide you with the knowledge required to load a FAT filesystem inside a GUID partition table using FatFS.
Adding GPT support to FatFS - AllThingsEmbedded
FatFs is an open source library used in many embedded devices to interface with FAT file systems in Block devices such as SD cards, flash drives, etc. It can load a FAT or ExFAT filesystem found inside a partition in an MBR partition table. However, it doesn’t provide support to find a FAT filesystem inside a GUID partition table. This blog post will provide you with the knowledge required to load a FAT filesystem inside a GUID partition table using FatFS.
https://allthingsembedded.github.io/2018/12/29/adding-gpt-support-to-fatfs/