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Theoretically, FAT32 could go up to 16TB with 4k drives, but it's limited to 8TB due to FAT32 maximum cluster number coded in 28bits instead of 32bits.
Thanks for the report about EmuNAND and 4k.
I guess I should limit it in the loader then (it's currently allowed past d2x v4).
FAT32:
Maximum FAT32 clusters : 28bits = 0x0FFFFFFF = 268 435 455
Maximum FAT32 sectors : 32bits = 0xFFFFFFFF = 4 294 967 295
With 512 bytes/sector, 32K/cluster = 2TB:
Number of sectors in 32K/cluster = 32 768/512 = 64 sectors/cluster
Maximum theoretical size : Max cluster * cluster size = 28 bits * 32k = 8 796 092 989 440 (8TB)
but usable size : Maximum usable sectors * sector size = 32bit * 512 = 2TB
With 4096 bytes/sector, 32K/cluster = 8TB:
Number of sectors in 32K/cluster = 32768/4096 = 8 sectors/cluster
Maximum usable size : Max cluster * cluster size = 28 bits * 32k = 8 796 092 989 440 (8TB)
Even if theoretical size : Maximum sectors * sector size = 32bit * 4096 = 17 592 186 040 320 (16TB)
Maybe using 64k/cluster will use full 16TB, but it will not work with all homebrew.
Though, using 4k/sector is already a problem with some homebrew.
Maximum FAT32 clusters : 28bits = 0x0FFFFFFF = 268 435 455
Maximum FAT32 sectors : 32bits = 0xFFFFFFFF = 4 294 967 295
With 512 bytes/sector, 32K/cluster = 2TB:
Number of sectors in 32K/cluster = 32 768/512 = 64 sectors/cluster
Maximum theoretical size : Max cluster * cluster size = 28 bits * 32k = 8 796 092 989 440 (8TB)
but usable size : Maximum usable sectors * sector size = 32bit * 512 = 2TB
With 4096 bytes/sector, 32K/cluster = 8TB:
Number of sectors in 32K/cluster = 32768/4096 = 8 sectors/cluster
Maximum usable size : Max cluster * cluster size = 28 bits * 32k = 8 796 092 989 440 (8TB)
Even if theoretical size : Maximum sectors * sector size = 32bit * 4096 = 17 592 186 040 320 (16TB)
Maybe using 64k/cluster will use full 16TB, but it will not work with all homebrew.
Though, using 4k/sector is already a problem with some homebrew.
Thanks for the report about EmuNAND and 4k.
I guess I should limit it in the loader then (it's currently allowed past d2x v4).