The Xbox 360 XL HDD and USB patches are now open-source on GitHub! These are the patches that extend the size limit of the internal SATA drive and external USB drives from 2 TB to 16 TB.

This was one of the most challenging projects I ever worked on. It involves significant updates to the Xbox 360’s I/O stack and various changes to other undocumented systems. This is also the first time the XDK version has been made public for those who may have been waiting for it.

A long-form writeup is planned at a future date detailing how everything works and all the challenges that were encountered through the development process. If you have any specific technical questions, feel free to leave them in the comments below.

FAQ

Q: Why are they being open-sourced now?
A: The plan was always to open-source the patches eventually, once they were considered complete. While there are still known issues, no new ideas have come to mind recently on how to solve them, so the time seemed right to release them now to see if anyone else might have creative ideas on how to solve the remaining issues.

Q: Is there anything new in this release compared to the last compiled patch release?
A: No – if you are a user, there is no update to flash. Today’s source code release is representative of the v4 HDD patch, v3 USB patch, and v1 combined patch.

Q: Are the patches now discontinued?
A: Not exactly, but there are relatively few people reporting problems with them, so it may be considered close to a finish project now.

Q: What are the known issues?
A: They are mentioned in the GitHub readme. If you are a user and don’t see an issue listed you think should be there, leave a comment below with the details.

Q: Can I use this release to make a Bad Update version?
A: For the USB version maybe, but not the HDD version right now.