3DS ROM Tool

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3DS ROM Tool
General
Author(s)3DSGuy
TypeUtility
Version2.9
LicenceMixed
Links
Download

"rom_tool" is a tool I wrote in light of the recently announced Gateway 3DS. It has three main features:

  • Read 3DS ROMs, and print information about them, including actual ROM file size, and minimum required 3DS FW etc.
  • Accurately trim 3DS ROMs, and be able to restore them again.
  • Extract the partitions from 3DS ROMs (and other NCSD Images, such as NAND Dumps)

ROM trimming and un-trimming is tested(to trim and un-trim correctly), and works with all 3DS ROM sizes, large(4GB) and small(128MB).

NOTE: In release v2.6 and onwards, there exists a feature called "Super Trim". This works by removing the update partition(in addition to unused bytes) from the ROM. However as this is removing used data from the ROM, the removed update partition CANNOT be restored, and the ROM is PERMANENTLY altered. As update partitions are approximately 30MB in size, Super Trimming offers little advantage over regular trimming when dealing with large ROMs. So Super Trimming a ROM should only be done when space is scarce.

NOTE: Super Trimmed ROMs are only compatible with Gateway Version 1.1a and above. This is because the update partition is removed, and under normal circumstances the 3DS would register an error. However in GW Version 1.1a and above, game card update check is bypassed, so removing the update partition will not affect playing the ROM.

HOW TO USE

This is a command line tool, so you have to use cmd.

View ROM/NAND Dump Info:

rom_tool -i Test.3ds

Extract ROM Partitions:

rom_tool -x [directory to extract partitions] Test.3ds

Trim ROM:

rom_tool -t Test.3ds

Super Trim ROM (Permanently remove update partition):

rom_tool -s Test.3ds

Restore ROM (Untrim):

rom_tool -r Test.3ds

Supported Operating Systems:

  • Windows 32bit/64bit (Tested on Windows 7/8) (executable included in download)
  • Mac OS X (Tested on 10.8.3) (executable included in download)


Change log (v2.9):

  • Extraction of NCSD Partitions should no longer bottleneck RAM
  • Save Encryption is now determined
  • The condition of the NCSD File Image, is displayed (Full Size, Trimmed, SuperTrimmed)
  • An issue has been identified in Linux, and Linux versions will not work with large (>=2GB) roms.
  • Checking the Size of the ROM has been improved