Where do I put my content?

One of the key differentiators between muOS and other CFW’s is its flexibility with content storage. Essentially, it most doesn’t care where you put things.

The only firm rule is that all your content must be in sub-folders under a folder named roms.

This can be on SD1, SD2 or both.

Example 

.
└─ ROMS
   ├── SEGA
   │    ├── Master System
   │    │   └── <game files here>
   │    └── Mega Drive
   │        └── <game files here>
   ├── Nintendo Entertainment Sytem
   │   └── <game files here>
   └── SNES
       └── <game files here>

How do I transfer content to the device?

Of course, you can always eject the SD card (shut down the device first!) and plug it into a card reader to transfer files from a computer. However, there are other options you may find more convenient.

Wireless file transfer (for devices with Wi-Fi)

  • Enable the “Configuration > Web Services > SFTP + Filebrowser” setting.
  • In a Web browser, connect to your device’s IP address on port 9090. You can find the IP address in the bottom-right corner of the muOS Wi-Fi Network app. (The full URL will usually look something like http://192.168.1.XX:9090/.)
  • The default user name and password are “muos”. This can be changed in the filebrowser settings.
  • You can also use an SFTP client (e.g., the sftp command on Linux, WinSCP on Windows, etc.). Connect to the same IP address on port 2022 using the user name and password given above.

USB file transfer via MTP

  • Change the “Configuration > General Settings > Advanced Settings > USB Function” setting to MTP, and then connect a USB cable from your device’s USB port to your computer or phone.
  • On some platforms, the file explorer will open automatically and show the contents of the device. Other platforms may require you to manually install and use an MTP application.
  • The quality of MTP implementations varies across platforms. Additionally, USB functionality on many of the devices muOS supports can be inconsistent at times. If the connection doesn’t succeed at first, try a different cable, a different USB port, or a different MTP program.

What about Multi-Disc Content?

Some systems split their content over multiple discs. The preferred way to handle these so that your content list isn’t cluttered with all the disc names is to use .m3u & .chd files.

A handy article on how to convert to CHD can be found here.

To prevent the individual discs appearing in the content list simply move them to a hidden subfolder. Folders can be hidden by prefixing the name with a . or _

Example

Here’s how you would setup a multi-disc game to only have one entry in the content list.

.
└─ roms
   └── Sony Playstation
        ├── .hidden
        │   └── <game discs here>
        └── Final Fantasy VII.m3u

In this example the Final Fantasy VII.m3u would contain the following.

.hidden/Final Fantasy VII (Disc 1).chd
.hidden/Final Fantasy VII (Disc 2).chd
.hidden/Final Fantasy VII (Disc 3).chd

Incorrect M3U Files

Please note that some created ROM sets like TinyBestSet come with incorrect M3U formatting and will need to be modified for it to work with muOS!

What about BIOS files?

muOS conforms to libretro standards for BIOS files.
For information around which particular BIOS you need, please consult their documentation:

https://docs.libretro.com/library/bios/

NOTE

muOS does not supply any BIOS files!

muOS requires that its BIOS files be located in MUOS/bios
Most files can be placed in the root of that folder unless otherwise specified by the libretro docs.

How does muOS know what my content is?

This is one of the key features of muOS.

muOS will attempt to determine the contents of your folders by matching the folder name with commonly used names.
It stores the list of known names in /mnt/mmc/MUOS/info/assign.json.
If muOS has detected a known name it will automatically assign a default core to that folder.

NOTE

muOS will never use a default core that requires a BIOS to function.

If muOS is unable to automatically assign a core, simply try launching some content.
At this point muOS will prompt you to select which system it’s for.

Example

If I attempt to launch content from my SNES folder it will prompt which system.
Here I’m selecting the system Nintendo SNES-SFC

You can then select which core you would like to use. In this case I’d select Beetle Supafaust.

Once done, muOS knows that folder contains Nintendo SNES content and will no longer prompt.

I chose poorly

What happens if you inadvertently choose a core you don’t want or like?
No problem. Simply hit SELECT on a game and it’ll prompt you to choose again!