mac68k-starter

A template for writing programs for the original Macintosh (128K/512K, 1984) in 68000 assembler - with Claude Code on the web, in your browser, or on your own Linux machine.

• mac68k-asm: assembler, linker and resource compiler in one program
• mac68k-disk: Mac floppy disk images
• Mini vMac: emulator, runs headless for tests
• CLAUDE.md: what Claude needs to know about the tools, the machine and the traps of 68000 programming on the Mac

Claude Code on the web

1. Use this template -> Create a new repository -> Private (your ROM will go in there).
2. Upload Mac128K.ROM (from your own Mac) and a System 3.x startup disk as System.dsk into the mac/ folder - see mac/README.md. Without them Claude can build but not test.
3. Give the Claude GitHub App access to the new repository (Configure -> Only select repositories). A private repository only shows up in claude.ai/code after that.
4. On claude.ai/code: open the environment menu (the cloud above the message box) -> Cloud -> Add cloud environment: name it mac68k, network access Trusted, and paste the contents of setup/cloud-setup.sh into Setup script.
5. Select your repository and the mac68k environment, and ask for a program, e.g. "Write a program that draws a bouncing ball. Quit on a click."

Claude builds it, boots it in the emulator, looks at the screenshots, and hands you a startup floppy - your system disk plus the program - as a download on a (private) Claude artifact. Unzip it and open Programs.dsk with Mini vMac, or write it to a real floppy.

On your own machine (Debian/Ubuntu)

sudo bash setup/cloud-setup.sh
./build.sh                      # builds src/Hello.* -> out/Programs.dsk, out/Test.dsk
tools/macemu.py "boot; shot start"

Files

src/	the programs: NAME.Asm, NAME.Link, NAME.R, NAME.Job
build.sh	build one program and put it on disk images
tools/macemu.py	run the Mac headless, click and type, take screenshots
setup/cloud-setup.sh	install everything (cloud environment or your machine)
mac/	your ROM and system disk (private repositories only)

Licence

MIT - see LICENSE. Mini vMac is GPL-2.0 and is built from its own repository.