The CDG5 project

The CDG5 project is an effort to thoroughly reverse-engineer Mac OS 9.2.2, the final release of the "Classic" Mac OS. We place an emphasis on supporting late-model PowerPC G4-based Macs, and also on hacking new features into the OS (e.g. support for >1.5 GB RAM).

Our work is spread over several GitHub repositories:

• 3 MB 68k ROM: http://github.com/elliotnunn/mac-rom
• 4 MB PowerPC rom, inc. NanoKernel: http://github.com/elliotnunn/powermac-rom
• Bootable "Mac OS ROM" file: http://github.com/elliotnunn/newworld-rom
• Disk-based Start Manager: http://github.com/elliotnunn/boot3
• Bootloader-NanoKernel shim: http://github.com/elliotnunn/wedge

Some tools:

• Get data into and out of HFS disk images and resource forks, robustly and portably
• Build software in the Mac emulator of your choice: http://github.com/elliotnunn/BuildCubeE
• Move resources around: http://github.com/elliotnunn/zcp
• Patch PowerPC binaries: http://github.com/elliotnunn/patchpef
• Patch 68k MPW code objects: http://github.com/elliotnunn/patchobj
• Extract 68k MPW code objects from a ROM: https://github.com/elliotnunn/unlink
• Graft a System Enabler onto a Mac OS ROM file: https://github.com/elliotnunn/enablifier

Most of our testing, and some of our discussion, takes place on the MacOS9Lives forums.