Start with a genuine 32X target
Marsdev provides a cross-platform Mega Drive and 32X toolchain. Its README distinguishes the 68000 toolchain from the additional SH toolchain needed for 32X work. Clone the documented dependencies and build the intended target rather than assuming that an ordinary Genesis compiler setup can produce a complete 32X program. Pin the repository commit, compiler version and build options in your project notes.
The original Sega 32X hardware manual is the reference for the CPU environments, registers and startup requirements. Read it alongside the framework's sample startup code. The SGDK project is useful for ordinary Mega Drive development, but its general Mega Drive scope should not be confused with an automatically complete 32X engine.
Prove the toolchain before designing the game
- Build an unmodified 32X example and retain its build log and output checksum.
- Run it in a supported emulator, recording emulator version and configuration.
- Use a flash cartridge that explicitly supports the output and test with a real 32X.
- Confirm visible 32X graphics, a base-console layer, input and audio.
- Repeat normal reset and cold boot before changing the sample.
A minimal scene should make the origin of each graphics layer obvious, for example with distinct labels or patterns. This makes a missing link cable or initialization error easier to identify. Keep development messages short and visible before adding a complex renderer. Change one subsystem at a time so a new failure can be traced to a specific build.
Design for the whole hardware arrangement
Document communication and ownership between processors using the framework's established patterns. Do not invent register writes from a screenshot of another project's code. Begin with bounded data transfers, then add performance counters or visible timing markers before optimizing. Test different supported regional timings if you claim them. Frame-rate-dependent movement and timeouts need particular attention during that test.
The Mega EverDrive Pro manual documents 32X cartridge support and restrictions involving the in-game menu and CD core. These restrictions affect deployment and debugging expectations. A project that needs CD hardware must state its complete configuration and cannot assume that every “Sega CD-capable” flash cartridge can supply it through a 32X. Keep a cartridge-only build and any CD-dependent build clearly named.
Publish a useful compatibility record
List required base models, 32X region, tested original hardware and flash-cartridge firmware. Include a source or buildable sample where possible, the license for code and assets, output checksums and a short reproduction sequence. A commercial-game patch should identify the exact original revision and distribute a patch where appropriate, without bundling assets you cannot redistribute.
Test saving separately from gameplay if the project supports it. An emulator save state is not evidence of working native persistence on hardware. Verify an intentional save, shutdown and reload. For crash reports, request the last visible marker, exact hardware arrangement and output checksum. These records let another developer reproduce the problem without guessing whether it came from an old executable, a missing video link or a different mapper.