The Nintendo 3DS has a 1GB NAND Flash chip.
Format
The format of the Nintendo 3DS's flash filesystem is currently undocumented. Reading of the flash chip is possible through pinouts on the motherboard and has been performed successfully but the data is encrypted and can't be understood without first decrypting it.
File System
Each NAND partition is formatted by a FAT file system.
Encryption
The NAND file system is encrypted using AES-CTR.
Partitions
| Name | Description |
|---|---|
| firm0 | Firmware partition. |
| firm1 | Firmware partition. |
| nand | CTR-NAND File System. (3DS) |
| twln | TWL-NAND File System. (DSi) |
CTR partition
Like SD, NAND savegames are stored at 00000000.sav under the data dir, for titles using NAND savegames. Also like SD, the TMD is stored under the titles' content dir as filename <ID>.tmd.
TWL partition
The structure of twln/title/ is exactly the same as DSi.(Same filenames under titles' data/content dir) The structure of twlp(TWL photo partition) is *exactly* the same as the DSi photo partition as well.