A CLI tool to create CTR (Nintendo 3DS) ROM images.
- NCCH Format Variants:
- CTR Executable Image (.cxi)
- CTR File Archive (.cfa)
- CIP (.cip) (These are the processes bundled with the kernel image)
- CTR Importable Archive (.cia)
- CTR Card Image (.cci/.3ds)
The native format storing code binaries and data archives for the 3DS is NCCH. NCCH files are comprised of:
- code/exheader/plainregion (used for code execution) (plainregion just lists included SDK library add-ons)
- icon (app title text, icon, HOME menu settings)
- banner (cbmd + cwav, i.e. the upper screen banner/sound shown on the homemenu)
- logo (the splash screen displayed after an application is launched from the homemenu)
- romfs (read-only filesystem used to store resources)
Typical uses for NCCH files include:
- Executable image (code+exheader+icon+banner+logo+romfs)
- e-Manual archive (accessed from homemenu) (romfs)
- Download Play child CIA archive (accessed from application) (romfs)
- Update Data archive (romfs)
- Standalone data archive (romfs)
- DLC index archive (icon+romfs)
- DLC archive (romfs)
The native format for gamecard images is CCI and is a NCCH container format. CCI files are limited to containing 8 NCCH files, and can contain NCCH files for applications titles only.
| NCCH | Required | Index |
|---|---|---|
| Executable image | YES | 0 |
| e-Manual archive | NO | 1 |
| DLP child CIA archive | NO | 2 |
| (New 3DS) Update Data archive | NO | 6 |
| (Old 3DS) Update Data archive | NO | 7 |
The native format for packaging NCCH files for install is CIA, which is also a NCCH container format. CIA files are limited to containing 65535 NCCH files and can be used to contain NCCH files for any title type. CIA files also contain signed data used by the 3DS for general title management and DRM. Installing custom CIA files on a 3DS which also uses eShop/SysUpdates is unwise as conflicts will likely occur.
Applications (Application/DlpChild/Demo/Patch/SystemApplication):
| NCCH | Required | Index |
|---|---|---|
| Executable image | YES | 0 |
| e-Manual archive | NO | 1 |
| DLP child CIA archive | NO | 2 |
System Applet/Module:
| NCCH | Required | Index |
|---|---|---|
| Executable image | YES | 0 |
System Data Archives:
| NCCH | Required | Index |
|---|---|---|
| Data archive | YES | 0 |
DLC:
The number of DLC data archives in DLC varies for each DLC.
| NCCH | Required | Index |
|---|---|---|
| DLC index archive | YES | 0 |
| DLC data archive | YES | Varies |
makerom [general args] [rsf args] [crypto args] [ncch 0 build args] [cci args] [cia args]
General Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-f <format> |
ncch/cxi/cfa/cci/cia |
Specify the output file format. cxi/cfa are aliases of ncch. |
-o <path> |
Valid file path. | Specify name/path for output file. Makerom will decided a name if this is not specified. |
-v |
not required | Enables verbose output. |
RSF Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-rsf <path> |
Valid file path | Specify the path to Rom Specification File (RSF). See below for creating RSF. |
-D<KEY>=<VALUE> |
This is used to substitute where $(<KEY>) exists in the RSF files with <VALUE>. This is useful for scripting. |
Crypto Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-target <target> |
t/d/p |
Specify key-chain. This affects encryption, signing and -desc template availability. t=test, suitable for homebrew. d=devkit(incomplete), suitable for devkits. p=retail(incomplete), suitable for production hardware. Not all RSA private keys are known, so d and p targets may not sign data properly. |
-ckeyid <index> |
Any value between 0-255 (inclusive). | Overrides the default common key used to encrypt CIA title keys. |
-showkeys |
none | Dumps loaded key-chain to stdout. |
NCCH Build Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-elf <file> |
Valid file path | Specify ELF. See below for creating ELF. |
-icon <file> |
Valid file path | Specify SystemMenuData icon. |
-banner <file> |
Valid file path | Specify banner. |
-desc <apptype>:<fw> |
<apptype>=app/ecapp/demo/dlpchild. <fw>=kernel version minor. |
Use a template for exheader/accessdesc. These are hard-coded, so not all firmwares have a template. A value from 1-7 can be used in place of 'kernel version minor'. A template shouldn't be used if the title needs "special" permissions, the RSF must be configured fully. |
-exefslogo |
none | Include logo in ExeFS. Required for usage on <5.0 systems. |
Arguments useful for rebuilding a NCCH file
| Argument | Acceptable values | Notes |
|---|---|---|
-code <file> |
Valid file path | Specify decompressed/plaintext exefs code binary. |
-exheader <file> |
Valid file path | Specify plaintext exheader binary. |
-logo <file> |
Valid file path | Specify logo. |
-plainrgn <file> |
Valid file path | Specify NCCH plain-region. |
-romfs <file> |
Valid file path | Specify an unencrypted RomFS binary. |
CCI Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-content <path>:<index> |
<path>=Valid file path. <index>=Any value between 0-7 (inclusive) |
Include a built NCCH file in the CCI container. -i can be used instead of -content. |
-devcci |
none | Build a debug CCI? |
-nomodtid |
none | Don't modify the TitleIds of NCCH files included to match NCCH0 |
-alignwr |
none | Align the offset for the Card2 writable region to the end of the last NCCH in the CCI. |
CIA Arguments
| Argument | Acceptable values | Notes |
|---|---|---|
-content <path>:<index>:<id> |
<path>=Valid file path. <index>=Any value between 0x0-0xFFFF (inclusive). <id>=Any value between 0x0-0xFFFFFFFF (inclusive) |
Include a built NCCH file in the CIA container. If <id> isn't specified, it will be generated randomly. -i can be used instead of -content. |
-major <version> |
Any value between 0-63 (inclusive) |
Specify the version major for the title. This cannot be used with -dver. |
-minor <version> |
Any value between 0-63 (inclusive) |
Specify the version minor for the title. This cannot be used with -dver. |
-micro <version> |
Any value between 0-15 (inclusive) |
Specify the version micro for the title. |
-dver <version> |
Any value between 0-4095 (inclusive) |
Specify the data-title version for the title. This cannot be used with -major or -minor. |
-dlc |
none | Specify this flag when building a DLC CIA. |
-rand |
none | Use a random title key to encrypt CIA content. |
General examples:
Create CXI
makerom -o sample.cxi -rsf sample.rsf -target t -elf sample.elf -icon sample.icn -banner sample.bnr -desc app:4
Create CFA
makerom -o sample.cfa -rsf sample.rsf -target t
Create CCI
makerom -f cci -o sample.cci -target t -i sample.cxi:0 -i sample.cfa:1
Create CIA
makerom -f cia -o sample.cia -target t -i sample.cxi:0:0 -i sample.cfa:1:1
Makerom supports building a NCCH file and including it automatically (as index 0) into a NCCH container:
Create CCI and CXI at the same time and include a CFA
makerom -f cci -o sample.cci -rsf sample.rsf -target t -elf sample.elf -icon sample.icn -banner sample.bnr -desc app:4 -i sample.cfa:1
Create CIA and CXI at the same time and include a CFA
makerom -f cia -o sample.cia -rsf sample.rsf -target t -elf sample.elf -icon sample.icn -banner sample.bnr -desc app:4 -i sample.cfa:1:1
Rebuilding CXI
makerom -o rebuild.cxi -rsf rebuild.rsf -target t -code rebuild/code.bin -exheader rebuild/exheader.bin -icon rebuild/icon.bin -banner rebuild/banner.bin -romfs rebuild/romfs.bin
Inspired by Nintendo's format for their makerom, a yaml configuration file is required for creating NCCH files. CIA/CCI can be created without using a RSF file, but default settings will be used.
For CXI, RSF files can be used to specify permissions, and access control settings. Makerom can use default settings by use of the "-desc" option, which removes the requirement for specifying them in the RSF file.
Sample RSF to be used with "-desc": download (link broken)
Sample RSF to be used without "-desc": download
The latest devkitARM used in conjunction with ctrulib can create ELF files compatible with makerom.
ELF files that are created using the official SDK are also supported by makerom.
See BUILDING.md.