This guide is work in progress. Please report any issues you may encounter and other feedback on github.

Marenthyu's Guide to Custom Firmware using SeedMiner


Using SeedMiner with a friend giving you your LFCS

You have a friend with Homebrew already, yay!
Before we continue, however:

If you do not have a dedicated graphics card, this will take FOREVER - you are better off asking someone else for help.

If you do have one, though, good! Please follow along:

Section One - movable_part1.sed

  1. Add your friend to your friendslist on the 3DS
  2. Let your friend add you to his Friend List on the 3DS
  3. Tell your friend to download SeedMiner and install or run seedStarter on their 3DS
    If your friend only has Userland homebrew, it may fail. Tell them to read the readme.txt in the seedminer .zip, it has instructions for that case.
  4. Your friend presses B to dump their friends movable_part1.sed's
  5. Your friend powers off their 3DS
  6. Your friend puts their SD Card into their PC
  7. Your friend sends you your movable_part1.sed, which they will find in the seedstarter directory on their 3DS; It will be prefixed with your Friendcode.
  8. Rename it to movable_part1.sed if it is not yet named that.
  9. Copy the file into a new folder.

Section Two - Checking Python


Now that you have that file, we need to make sure you have python installed.

  1. Open a command Prompt by typing CMD into the start menu search bar and pressing return
  2. In the new black window, type py -3 --version
    • If it reports Python Version 2.x.x, you have Python 2 and should install Python 3 instead from python.org.
    • If it reports Python Version 3.x.x, you have Python 3.
    • If it complains, you either have Python 2 or no Python.
      • Go to python.org and download and install the most recent Python 3 version, then redo this part to confirm it worked.
  3. Type py -3 -mpip install pycryptodomex
    • If it does not give an error, you are good to go.
    • If you do get an error, try launching the command prompt as administrator by right-clicking the entry in the windows search and selecting run as Administrator; then try again.

Section Three - Downloading SeedMiner and adding your ID0


Next, we will add your ID0 to your movable_part1.sed. Without it, the file is virtually useless.

  1. Download the latest release of SeedMiner from here
  2. Extract the zip file
  3. Move your movable_part1.sed into the seedminer directory you just extracted, so seedminer_launcher3.py and movable_part1.sed are in the same directory.
  4. Next to the seedminer_launcher3.py file, hold SHIFT and right click, then select Open PowerShell Window here... or Open Command Prompt here...
  5. Type py -3 seedminer_launcher3.py update-db into the new window.
  6. Wait for it to finish, then type py -3 seedminer_launcher3.py id0 [YOUR ID0 HERE] - replace [YOUR ID0 HERE] with your ID0 we acquired before.
  7. If it succeeded,
    • And you have a graphics card, type py -3 seedminer_launcher3.py gpu
    • And you don't have a graphics card, type py -3 seedminer_launcher3.py cpu
      I repeat:
      If you do not have a dedicated graphics card, this will take FOREVER - you are better off asking someone else for help.
  8. If it succeeded, it will now take anywhere from 1 minute to an hour, depending on your graphics card. (It MAY take longer.)
  9. Wait.
  10. If it finished, you will now have a movable.sed and a .bin file - feel free to share the .bin file on the forum.
    • If the current offset exceeds about +-1000, you most likely did something wrong, but it is possible to have this bad of a hit every now and then, but it is better to make sure you did everything right at this point.
Once you have your movable.sed continue with the DSiWare Injection Service