bsnes-jg in RetroArch: Source-Based Setup Guide

bsnes-jg is a cycle accurate emulator for the Super Famicom / Super Nintendo Entertainment System that also covers the Super Game Boy, BS-X Satellaview, and Sufami Turbo. It is a fork of bsnes v115 and its documented changes after the fork include a higher quality resampler with settings, improved performance without loss of accuracy, portability improvements, removal of accuracy-reducing hacks, increased standards compliance, and translation to the C++ Standard Library (ISO C++11).

Prerequisites and core identity

The bsnes-jg core's library name is 'bsnes-jg'. It is licensed under GPLv3, and the core has been authored by byuu and Rupert Carmichael (carmiker).

Supported content file extensions

• .sfc
• .smc
• .gb
• .gbc
• .st
• .bs

Firmware and BIOS files

Required or optional firmware files go in the frontend's system directory. The documentation lists the following co-processor firmware filenames along with their md5sums.

Subsystem workflows

bsnes-jg supports the Super Game Boy, BS-X Satellaview, and Sufami Turbo via the Subsystem API. The documented subsystem identifiers are sgb, bsx, sufami (one cart), and sufami2 (two carts).

For Super Game Boy, you need a Game Boy ROM (.gb or .gbc) and a Super Game Boy ROM. For BS-X Satellaview, you need a BS Memory dump (.bs) and the BS-X BIOS ROM. For Sufami Turbo, you need Sufami Turbo ROMs (.st) and the Sufami Turbo ROM.

The documented command-line example for the Super Game Boy subsystem is shown below. Replace the placeholders with paths on your own system.

retroarch -L {path to bsnes core} {path to Super GameBoy ROM} --subsystem sgb {path to GameBoy rom}

In the RetroArch GUI, the documented Super Game Boy flow is to load the Game Boy ROM through 'Load SuperGame Boy' in RetroArch's Main Menu, then load the Super Game Boy BIOS ROM through 'Load SuperGameBoy' in RetroArch's Menu Menu, and finally start the content by selecting 'Start GameBoy' in RetroArch's Menu Menu.

Loading MSU-1 enhanced ROMs

MSU-1 is supported. To load an MSU-1 enhanced ROM, load the .sfc file that sits in the same directory as the .msu file and the audio tracks.

Core options

The core exposes the options listed in the tables below. Defaults are shown in the tables in the complementary structured section. Several options note that a restart is required to take effect, and the Internal Run-Ahead option is documented as having very high system requirements.

Save and state directories

Cartridge-based battery saves are stored as *.srm files and Real Time Clock data as *.rtc files in the frontend's save directory. States are stored as *.state# files in the frontend's state directory.

Controllers and multitap

User 1 supports the Gamepad and the SNES Mouse. User 2 supports the Gamepad, SNES Mouse, Multitap, SuperScope, and Justifier. Activating multitap support in compatible games is configured by switching to the Multitap device type for User 2.

Frontend feature support

Supported frontend-level features include Restart, Screenshots, Saves, States, Rewind, Core Options, Memory Monitoring for achievements, RetroArch Cheats, Native Cheats, Controls, Remapping, Subsystem, Softpatching, and Crop Overscan. Unsupported items include Netplay, Multi-Mouse, Rumble, Sensors, Camera, Location, Disk Control, Username, Language, and LEDs.

Documented scope and compatibility

The documentation states that the bsnes-jg core is compatible with all officially released SNES/SFC titles. That is the documented scope; it is not an independent verification of every title or ROM variant, and it does not extend to unofficial or hacked content.