ROM set and assets

86Box relies on a set of ROM dumps gathered from physical hardware to emulate it. This includes the system BIOS, as well as any option ROMs used by expansion cards. Additionally, some features require an asset pack installed separately from the ROM set.

The ROM set and asset pack are organized into several directories for each device type, each of which contains futher subdirectories for each machine or device model or category.

Note

The expected file names of the ROM dumps and their locations within the set are hardcoded in the emulator. If you rename them or add your own dumps with different file names, the emulator will not be able to make use of them.

Search path

The emulator utilizes a search path mechanism to locate ROMs. By default, the following locations are considered:

  1. roms subdirectory in the VM path

  2. roms subdirectory in the same directory as the emulator executable

  3. Platform-specific locations

A custom location can be specified by using the -R or --rompath command line argument, which then precedes any other considered locations.

Tip

The list of all paths searched when loading ROMs is printed to the log and standard output when 86Box starts.

Windows

The following locations are searched on Windows:

  1. %LOCALAPPDATA%\86Box\roms

  2. %PROGRAMDATA%\86Box\roms

Unix

86Box honors the XDG base directory specification on Linux and other Unix-compatible platforms. The following locations are searched:

  1. $XDG_DATA_HOME/86Box/roms

  2. 86Box/roms subdirectory in each path listed in $XDG_DATA_DIRS

This usually resolves to ~/.local/share/86Box/roms, /usr/local/share/86Box/roms and /usr/share/86Box/roms (in order).

macOS

The following locations are searched on macOS:

  1. ~/Library/Application Support/86Box/roms

  2. /Library/Application Support/86Box/roms

Note

If 86Box cannot find any ROM dumps even after you extracted the set into one of the directories listed above, please make sure that the roms folder name does not contain a hidden extension. This can be fixed by selecting the folder in Finder, choosing Get Info in the context menu or the File menu, and renaming the folder in the Name & Extension section of the information window.

Asset pack

Some features also require an asset pack, which is included with release builds of 86Box downloaded from GitHub, as the assets folder inside the downloaded archive on Windows, or embedded within the application on Linux and macOS. It must be installed manually in other situations, such as when using advanced builds.

Currently, the floppy audio and hard disk audio features require the asset pack to be installed.

The same search path mechanism described above applies to the asset pack, but with a directory named assets instead of roms. The -A or --assetpath command line argument can be used to specify a custom location.