GameAndWatch_MiSTer/rom generator

Game & Watch ROM Generator

This folder contains the ROM packaging tooling for the Game & Watch MiSTer core.

The generator converts MAME Game & Watch artwork and ROM zips into .gnw packages that the FPGA core can load. It does not include MAME ROMs or artwork.

Contents

• src/ - Rust source for fpga-gnw-romgenerator
• Cargo.toml / Cargo.lock - Rust build metadata
• extraction/ - TypeScript helper for generating manifest.json from MAME's hh_sm510.cpp

Requirements

• Rust toolchain with cargo
• Node.js and npm, only if regenerating manifest.json
• A MAME-style folder containing artwork/ and roms/

Expected MAME input layout:

/MAME Folder/artwork/gnw_dkong.zip
/MAME Folder/roms/gnw_dkong.zip

Build The Generator

From the repository root:

cargo build --manifest-path "rom generator/Cargo.toml" --release --locked

The binary will be written to:

rom generator/target/release/fpga-gnw-romgenerator

You can also run it without separately invoking the built binary:

cargo run --manifest-path "rom generator/Cargo.toml" --release --locked -- --help

Generate Or Provide The Manifest

The generator needs a manifest.json describing supported devices, CPU types, ROM hashes, screen setup, and input mapping.

To regenerate it from a local MAME source checkout:

cd "rom generator/extraction"
npm ci
npm run build -- /path/to/mame/src/mame/handheld/hh_sm510.cpp ../manifest.json

That writes rom generator/manifest.json, which the Rust generator can use directly.

Generate ROM Packages

From the repository root:

cargo run --manifest-path "rom generator/Cargo.toml" --release --locked -- \
  --manifest-path "rom generator/manifest.json" \
  --mame-path "/path/to/MAME Folder" \
  --output-path "/path/to/output" \
  supported

The output directory must already exist.

The supported filter includes SM510, SM511, SM512, SM510 Tiger, and SM5a titles. SM511/SM512 packages include the fixed 4 KiB program ROM area plus the appended 256 byte melody ROM.

On MiSTer, generated .gnw files belong in:

/games/Game and Watch/

Useful Filters

Generate one game:

cargo run --manifest-path "rom generator/Cargo.toml" --release --locked -- \
  --manifest-path "rom generator/manifest.json" \
  --mame-path "/path/to/MAME Folder" \
  --output-path "/path/to/output" \
  specific gnw_dkong

Generate only installed supported games:

cargo run --manifest-path "rom generator/Cargo.toml" --release --locked -- \
  --manifest-path "rom generator/manifest.json" \
  --mame-path "/path/to/MAME Folder" \
  --output-path "/path/to/output" \
  --installed \
  supported

The Rust CLI is the source of truth for options:

cargo run --manifest-path "rom generator/Cargo.toml" --release --locked -- --help