Docomo Phones by NEC

Check the dumping hardware overview for a list of known preservation hardware.

If you need help, please come chat with us on the VGPC or No-Intro discord servers.

• Docomo phones by NEC use a very similar bootloader to the one used in Panasonic and Casio Docomo phones.
• When an NEC phone is properly connected to a debug cable, it will light up for approximately one second, and then turn off.
• We currently do not know how to extract NAND data from NEC phones between approximately N902i - N703iμ. These phones are also challenging to connect to PC. It may take multiple tries for your PC to detect one of these phones. Sometimes, these phones connect better after booting up once.

Extracting Data

1. ktdumper

Reading File Systems

1. EPOC32
2. JFFS2

Ktdumper is a tool for extracting data from feature phones that are compatible with the Foma debug adapter, which includes all Docomo phones and select SoftBank phones. Please note that ktdumper will not work unless you have the Foma debug adapter.

Ktdumper is compatible with Linux and WSL (Windows System on Linux). It can be used as a command line tool or as a live Linux iso with a GUI.

Ktdumper Command Line

sudo ./ktdumper.sh d904i dump_nand

Ktdumper Live Iso

The JFFS2 file system can be extracted with Jefferson, which runs on Python. You can install Jefferson in a pre-existing Python using pip:

sudo apt-get install python3-pip
sudo pip3 install jefferson

The following command creates a folder called “jffs2_extracted” to contain the data extracted from nand.bin.

sudo jefferson -d jffs2_extracted nand.bin

Note: You may see the error

data_crc does not match!

The dump may still be working. Let it continue until the process is complete before trying other steps.

Troubleshooting

If the jffs2_extracted folder contains no data, the offset will need to be removed from the .bin file.

You can determine the offset two ways:

• Using binwalk, look for the address where the JFFS2 file system begins.

binwalk nand.bin

• Using a hex editor such as HxD, look for the following four bytes:

85 20 19 E0

Or

85 19 02 E0

Delete all data before those four bytes and try again to extract with Jefferson.

Note: It is not possible to undelete files from a JFFS2 file system.

Current tools for removing the SSR200 FTL are meant to work on Linux or WSL (Windows Subsystem for Linux)

1. Install PyFatFS. You can use pip.

   sudo apt-get install python3-pip
   sudo pip3 install pyfatfs

2. Download the fs-tools repository from Github
3. PyFatFS must be patched in order to read docomo SSR200. Give install.sh permission to run with the following command:

   chmod +x install.

   Then run install.sh

   sudo ./install.sh

The following steps are different based on whether you are trying to extract SSR200 or SSR200 “Old Flavor”

Regular SSR200

1. Copy nand.bin and nand.oob to fs-tools/ssr200. With all files in the folder (nand.bin, nand.oob, and all of the ssr200 fs-tools), run the following command:

   python3 run.py nand.bin

SSR200 “Old Flavor”

1. Install Sleuthkit

   sudo apt install sleuthkit

2. Copy nand.bin and nand.oob to fs-tools/ssr200_old_flavor. With all files in the folder (nand.bin, nand.oob, and all of the ssr200 fs-tools), run the following command:

   run.sh nand.bin

Current tools for extracting XSR1 require Windows.

1. Download rfs_dumper.exe from Github
2. The input file should be stripped of everything before the first 91 5A 49 2C header. In HxD, you can do this by going to the menu and selecting Search>Find, then selecting the Hex-values tab and pasting in 91 5A 49 2C. Once you find this location, delete everything before it. Save this new file as input.bin.
3. Place onenand.bin, onenand.oob, and rfs_dumper.exe in one folder. Open a terminal in the folder with the dump (onenand + oob) and rfs_dumper.exe. Use the following command:

   .\rfs_dumper.exe input.bin output.bin

The file system can now be read and extracted with TestDisk.

Once you've dumped your games, it's time to generate and submit metadata to a preservation project for validating and cataloging. See the dump submission instructions for more information.