emulator: Mandarine
type: standalone
core_classification: community_fork
source: "https://github.com/ptyfyre/mandarine-neo"
upstream: "https://github.com/ptyfyre/mandarine-neo"
profiled_date: "2026-08-08"
source_commit: "7f8ec960b6183be4350bca099d23ddd9fc7bcaa3"
core_version: "1.3.0"
display_name: "Nintendo - 3DS (Mandarine)"
cores:
  - mandarine
  - mandarine-qt
systems:
  - nintendo-3ds
mode: standalone

notes: |
  Citra fork, renamed Mandarine-Neo at release 1.3.0. External files live in
  sysdata/ and nand/ under the user directory: user/ next to the executable when
  that directory exists, otherwise Mandarine on Windows and macOS and
  mandarine-emu on Linux, with Citra and citra-emu kept as legacy locations.
  ref: src/common/common_paths.h:16-70, src/common/file_util.cpp:770-839

  InitKeys reads boot9.bin then aes_keys.txt. Encrypted content needs one of the
  two; a ROM without crypto reads neither.
  ref: src/core/hw/aes/key.cpp:315-324, src/core/file_sys/ncch_container.cpp:200-210

  Failure to derive a key or to find a seed marks the content undecryptable and
  loading stops with ErrorEncrypted.
  ref: src/core/file_sys/ncch_container.cpp:219-223, src/core/file_sys/ncch_container.cpp:236-280, src/core/file_sys/ncch_container.cpp:347-349

  System archives resolve to the NAND title tree. Shared font, Mii data, country
  list and bad word list fall back to open-source replacements built into the
  binary when the title is absent.
  ref: src/core/file_sys/archive_ncch.cpp:126-179, externals/open_source_archives/Readme.md

  The embedded shared font only answers title low ID 0x00014002. CHN, KOR and TWN
  resolve to 0x00014102, 0x00014202 and 0x00014302, which fall through to
  shared_font.bin and then to ErrorSystemFiles, reported as recoverable.
  ref: src/core/hle/service/apt/apt.cpp:195-213, src/core/hle/service/apt/apt.cpp:276-291, src/mandarine_qt/main.cpp:3209-3215

  ClCertA is read from NAND title 0x0004001B00010002 and its ctr-common-1-cert.bin
  and ctr-common-1-key.bin members are decrypted with the KeySlot 0x0D normal key.
  Both the title and the key slot are needed for authenticated HTTPS.
  ref: src/core/hle/service/http/http_c.cpp:1963-2036

  System titles are downloaded and installed in-app from the Nintendo CDN, so the
  NAND title tree is not user-supplied.
  ref: src/mandarine_qt/configuration/configure_system.cpp:672-678, src/core/hle/service/am/am.cpp:536, src/core/nus_download.cpp:12-13

  DumpKeys.gm9, a GodMode9 script producing aes_keys.txt and seeddb.bin, ships in
  the tree and documents sysdata/ as their destination.
  ref: dist/dumpkeys/README.md, dist/dumpkeys/DumpKeys.gm9

  The plugin loader scans sdmc/luma/plugins/<title id>/ for any .3gx file and
  falls back to sdmc/luma/plugins/default.3gx. Plugins carry no fixed identity.
  ref: src/core/hle/service/plgldr/plgldr.cpp:112-146

  mcu.dat holds per-installation MCU state that the emulator writes itself when
  the file is absent or carries the wrong magic.
  ref: src/core/hle/service/cfg/cfg.cpp:734-756, src/core/hle/service/cfg/cfg.h:425-439

  sector0x96.bin is defined but read by no code path.
  ref: src/common/common_paths.h:70

files:
  - name: boot9.bin
    path: sysdata/boot9.bin
    system: nintendo-3ds
    required: false
    size: 65536
    validation: [size]
    note: "AES key section read at offset 55760, RSA modulus and exponent at 0xB3E0 and 0xB4E0"
    source_ref: "src/core/hw/aes/key.cpp:137-206, src/core/hw/rsa/rsa.cpp:49-80, src/common/common_paths.h:69"

  - name: aes_keys.txt
    path: sysdata/aes_keys.txt
    system: nintendo-3ds
    required: false
    note: "key slots, common keys, DLP and NFC key Ys and NFC secrets, one per line"
    source_ref: "src/core/hw/aes/key.cpp:208-311, src/common/common_paths.h:68"

  - name: seeddb.bin
    path: sysdata/seeddb.bin
    system: nintendo-3ds
    required: false
    note: "game seed database for 9.6+ titles; an empty database is written when the file is absent"
    source_ref: "src/core/file_sys/seed_db.cpp:12-58"

  - name: shared_font.bin
    path: sysdata/shared_font.bin
    system: nintendo-3ds
    required: false
    hle_fallback: true
    note: "legacy path, tried after the shared font system archive; decompressed BCFNT with the 0x80 byte APT header"
    source_ref: "src/core/hle/service/apt/apt.cpp:254-270, src/common/common_paths.h:67"

  - name: CTCert.bin
    path: sysdata/CTCert.bin
    system: nintendo-3ds
    required: false
    size: 384
    validation: [size]
    note: "console client certificate; signature type must be 0x010005 and the issuer one of the two Nintendo CA G3 strings"
    source_ref: "src/core/hle/service/am/am.cpp:2427-2454, src/core/hle/service/am/am.cpp:83-93, src/core/hle/service/am/am.h:95"

  - name: SecureInfo_A
    path: nand/rw/sys/SecureInfo_A
    system: nintendo-3ds
    required: false
    size: 273
    validation: [size]
    note: "console region and serial number; loaded on a size check alone, and paired with LocalFriendCodeSeed_B"
    source_ref: "src/core/hle/service/cfg/cfg.cpp:608-610, 689-709, src/core/hle/service/cfg/cfg.h:180-186"

  - name: LocalFriendCodeSeed_B
    path: nand/rw/sys/LocalFriendCodeSeed_B
    system: nintendo-3ds
    required: false
    size: 272
    validation: [size]
    note: "friend code generation seed; loaded on a size check alone, and paired with SecureInfo_A"
    source_ref: "src/core/hle/service/cfg/cfg.cpp:604-606, 711-732, src/core/hle/service/cfg/cfg.h:188-193"