The DR-DOS/OpenDOS Enhancement Project

I think, that the external driver will be a reasonable thing: exFAT file system has no short file name support and keeps names of files in UNICODE. Design of directory entries significantly differs from FAT16 and FAT32, and moreover, exFAT doesn't use FAT chains for not fragmented files, so it may be reasonable to not modify the DOS kernel. But the design strongly resembles FAT12/16/32.

P.S. Now I'm trying to implement cross-platform utility for reading files from exFAT partitions.