migration.md

June 8, 2023 ยท View on GitHub

Migrating a project to Marsdev

In General

  • The toolchain path variable is MARSDEV, default /opt/toolchains/mars.
  • From there, stuff related to M68000 (MD CPU) is in m68k-elf, for SH-2 (32X CPU) sh-elf.

Marsdev was originally forked from Gendev, but there are some paths that may be a level up or down from what they were. Compare the paths in your Makefile with those in an example project and fix them accordingly.

From SGDK (Official Windows releases)

SGDK projects are expected to work without changes and can be compiled in the usual way.

If you get file/path not found errors, make sure the GDK environment variable is set, and note that paths on most Unix filesystems are case-sensitive.

From an old dated release to v1.0.0-rc1 or later

The default installation path has changed from ${HOME}/mars to /opt/toolchain/mars. In addition, tools that were previously installed to mars/bin are now installed to mars/m68k-elf/bin instead. You may need to update these paths in your project's Makefile.

The below applies only to SGDK projects:

SGDK integration had some annoying bugs and the following changes were made, both to resolve those bugs, and make maintaining the integration easier:

  • SGDK's built in Makefiles are now used with minimal changes instead of a completely custom one.
  • SGDK bin, include and lib paths are moved into m68k-elf instead of being at the root.
  • A GDK variable is set to the path $MARSDEV/m68k-elf.

In the best case scenario, you would only have to do the following:

  1. Replace your Makefile with the one from the SGDK example project
  2. Delete sega.s, and make sure rom_head.c is in src/boot (create if it doesn't exist).

Note that the new Makefile is just a wrapper that runs SGDK's makefile.gen.