Yabause in RetroArch: Source-Based Guide to the Saturn Core

Yabause is an open-source Sega Saturn emulator built with portability in mind and rendered entirely in software. According to the official libretro documentation, it has gone without updates for years and upstream appears to be dead. This guide summarizes what that documentation states about running the Yabause core through RetroArch.

What the Documentation Covers

The source page is a library entry for the Yabause core: it identifies the core, lists its authors and license, states accepted content formats, describes BIOS handling, tabulates core features, and records the save, state and reported output values. It does not describe a step-by-step installation or configuration walkthrough.

Core Identity and Licensing

• - The Yabause core is authored by Guillaume Duhammel, Theo Berkau and Anders Montonen.
• - The core is licensed under GPLv2.
• - The emulator is software rendered, meaning rendering is handled on the CPU rather than through a hardware-accelerated path.

Accepted Content Formats

The documented supported file extensions for Yabause content are .cue, .iso, .ccd, .mds, .chd, .zip and .m3u. Loading a disc image in one of these formats is the documented way to start a game; this guide does not provide or point to any game files, and you must supply your own legally obtained content.

BIOS: Optional in Principle, Required for M3U

The BIOS file named in the documentation is saturn_bios.bin. It is listed as optional, and the documentation notes that the built-in emulated BIOS is not perfect and offers lesser compatibility, so installing a real BIOS is highly recommended. However, because multi-disc Saturn games are independent discs that send the player back to the BIOS screen when discs are switched, the real BIOS is required if you intend to load .m3u playlists for multi-disc titles.

Supported and Unsupported Features

The documentation tabulates the following feature support for the core. Supported means the feature is listed with a check mark; not supported means it is listed with a cross.

Reported Output Values

• - Core provided FPS: 60 for NTSC games and 50 for PAL games.
• - Core provided sample rate: 44100 Hz.
• - Core provided aspect ratio: 4/3.

Save and State Files

The documentation records the following file naming for the core's save and state output. Saves are written as 'content-name'.srm and states are written as 'content-name'.state#.

Documentation Limitations

This source page does not include installation steps, directory configuration, per-game compatibility notes, performance expectations or troubleshooting content. Upstream development is described as apparently dead, which means no further updates or fixes should be assumed from that project. Anyone relying on this page should treat the details above as a description of the core as documented, not as a verified functional result.

Summary

Yabause is a portable, software-rendered, GPLv2 Saturn emulator available as a libretro core. It accepts common disc image and playlist formats, works without a BIOS in principle but needs a real BIOS for .m3u multi-disc playlists, supports saves, states, controls, cheats and disk control, and does not support rewind, netplay or rumble. The official page stops short of a full setup walkthrough, so configuration steps would need to come from another source.