What is this?
muOS is a custom firmware primarily available for handheld devices. It’s configurable, themeable, friendly and easy to use.
The current supported devices are:
- Anbernic RG28XX
- Anbernic RG34XX
- Anbernic RG34XXSP
- Anbernic RG35XX 2024
- Anbernic RG35XX PLUS
- Anbernic RG35XX H
- Anbernic RG35XX Pro
- Anbernic RG35XX SP
- Anbernic RG40XX H
- Anbernic RG40XX V
- Anbernic RGCUBEXX
- TrimUI Brick
- TrimUI Smart Pro
What you need
You’re going to want two SD cards for this – trust me on this one, muOS is not a custom firmware that thrives on a single SD card as they usually do full releases like this where it overwrites everything, but if you have a second SD card, you can keep all your data, saves, ROMs and all that on your second card so they don’t get wiped.
So I would suggest a 32GB or 64GB card for the operating system card and a 128GB or 256GB card for your ROMs and settings card.
Plus you’ll need a USB SD card reader.
Backing up an existing muOS install
First things first, for those of you that already are using muOS and I’m going to limit this to those of you on Canada Goose or newer – if you’re on an older version than that, you’d want to do a fresh install.
Those using two SD cards
For Canada Goose and newer, those using two SD cards, let’s backup all your stuff.
Head to Configuration and then Storage Options – if you followed one of my previous guides and set this all to SD2, hey you’re set, nothing you need to do.
All your data is on your 2nd SD card.
If you didn’t, go one by one and push X to Sync to SD2 until they all are moved over to your 2nd SD card.
Those using one SD card
If you’re using one SD card, head to Configuration and then Device Backup, push X to Toggle All to make sure they all say Included, then head to the bottom and choose Start Backup.
This will take some time.
Once done, you want to connect your SD card to your PC, and you need to copy your ROMs folder to your PC to back those games up, and then head inside of the BACKUP folder, and you want to copy the MustardOS FullBackup file to your PC as well.
Flashing muOS
Okay, let’s start first with grabbing the latest muOS release from their website, go ahead and download the image.
I suggest using the MEGA link as I found it to be more reliable.
You’ll need to grab the image that matches your device model.
We’re also going to need Rufus to flash this image to your SD card, which you can grab from the Rufus website – the portable version is fine.
Open Rufus, make sure the device listed is your connected SD card to the PC – the operating system card if you’re doing two, then click select and choose the image you downloaded from the muOS website.
Then click Start and let it do its thing.
When it’s done, pop that into the OS slot on your device, usually says TF1 and turn on the device.
You can adjust your date/time here, or language, but I just choose Install – date/time can get updated later via WiFi automatically.
Formatting second SD card (for those doing two cards)
While that’s happening, for those that want to use two SD cards, we can format that card otherwise one card users can skip this.
Go ahead and connect your second SD card to the PC, and open Rufus.
Make sure the device is your SD card, then choose non bootable for boot selection and make sure file system is exFAT then click Start.
When it’s done, you can eject.
Wait for the device to finish doing the setup it was doing, and making sure you shutdown after that, you can now insert this second SD card into the second slot and turn on the device.
Head to Config then Storage and for any two card users, check to see if it says SD2 or SD1 here.
If it says SD1, go one by one and push X to migrate to SD2 for everything.
This puts all our data on the second SD card.
That way, the next time there’s an muOS update, it’ll be super easy for you to keep everything and not delete it all when updating.
Going forward, for two SD card users, anything I talk about will be on your second SD card, so you can safely ignore the first unless I bring it up.
Shutdown the device after you’ve done all that and put your SD card into the PC.
Adding ROMs & BIOS
The ROMS folder is where you put your ROM folders, and you can name them whatever you want.
So, for example, for your Game Boy Advance ROMs, you can create a folder just called gba and then put all your GBA games inside of it – the name doesn’t matter, you can name the folder anything you like.
With the above, they would be in the ROMS/gba folder. Repeat for any other systems you have.
For BIOS files, they go inside of the MUOS/bios folder.
If you’re confused as to what ROMs and bios files are, I have a video on that subject below – but ROMs are games, BIOS files are system files that are required for CD based systems like PS1, Dreamcast and so on. You can see a list of required BIOS files here: Recommended BIOS Files.
Restoring existing muOS backups for single SD card users
For those that did a Device Backup, let’s go restore your stuff – head to Applications, Archive Manager, and you should see your backup, just push A to start the restore process.
muOS Settings
So at this point, you’ve added your ROMs, and your BIOS files, we can jump into settings so pop the SD card back into your device and turn it on.
Launching Games
Head to Explore Content and this is where your games are and where you launch them, you should see all your system folders here.
If you push X on any of them, you can see what emulator or core they’re using for that system – so mGBA for GBA and we can change that if we want to to another core.
I’d leave all this as default.
You do want to make sure that each system does have a core or emulator set though, so just check each system for it and if it’s missing, add one.
If you head into a system folder, there’s all your games – you can do the same thing here by pushing X to change an emulator or core on a per-game basis if you want to.
Don’t worry about artwork just yet, we’ll add that later.
If you push Y, you can add your games to a Collection for easier browsing – I have a pokemon collection already, or you can push Y to create a new one that you want and put your games inside.
Collection
Collection is up next, and let’s go ahead and create a collection called Pokemon.
This will be if you want to create groups of games.
All you need to do is find the game you want to add to a collection in the Content list, push Y, select the Pokemon collection and then A to add. Easy.
History, Information & Applications
History is your history of games.
Info is just information about the firmware and storage space, input tester, that sort of thing.
Apps is where all your apps will be, Dingux commander is a file manager for example, Portmaster and so on.
RetroArch Settings
RetroArch is fully locked down on muOS, you can’t make any changes – however, we can enter our RetroAchievements information so if you head to Settings and Achievements, you can login with your information.
We haven’t connected to WiFi yet so they won’t work just yet, but that’s the only change we can make.
For advanced users, I’ll show you how to open up RetroArch later if you want to.
Make sure to head back to Main Menu in RetroArch, Configuration File, Save Current Configuration to save your changes here for Achievements if you want them.
Config
Head to Configuration and then General Settings.
You can adjust brightness and volume, or use a hotkey of Menu + Volume keys to adjust brightness which is easier.
You can also set where the device loads to on startup, if you want it to go right into the last game you were playing and so on.
Date & Time
Date and Time is where you can update your date and time, but usually you just need to set your Timezone.
Advanced Settings
Scroll down to RetroArch Network Wait and if you’re using RetroAchievements, enable this.
It waits for the network to connect before loading a game, insanely useful.
Right under that is RetroArch Config Freedom.
If you really want to edit RetroArch, you need to enable this to do so, but I don’t suggest it unless you really know what you’re doing.
Lastly there’s Device Rumble if you want that.
Connectivity
Back out and now into Connectivity then into Wi-Fi Network.
Push X to scan for your WiFi and then connect to it with your password.
Push Connect to connect.
One thing I want to point out here, special tip especially for RetroAchievements users – if you know how to setup a static IP, I would suggest doing that instead of DHCP.
DHCP can take 30 seconds or so to jump into a game with RetroArch Network Wait enabled, whereas with static IP, it’s like 3 seconds.
Just a small tip.
Back out and into Web Services and if you want to use a web browser on your PC to manage files on muOS, enable SFTP or if you want to use Syncthing, enable Syncthing.
Themes
Back out and into Customisation.
Let’s head into Theme Picker and then Theme Download.
Once that’s done, you’ll see a whole list of available themes for your device, just push on whatever you want to use it!
Interface
Back out and into Interface Options and I like enabling Network to see the network icon to know I’m connected in the top right.
And that’s it from a settings perspective.
Launching a game & Hotkeys
Let’s go ahead and launch a game by finding one in Explore Content and boom we’re in.
Let’s talk about the hotkeys you have available to you, which are all on muOS’ website.
- Menu + X for RetroArch Menu.
- Menu + START to exit a RetroArch game.
- MENU + R1 to fast forward.
- MENU + R2 for Save State.
- MENU + L2 for Load State.
- MENU + Y for Show FPS.
Scrappy – For Box Art
Alright as promised, last for today is artwork scraping and we need to use a program called Scrappy to do so.
Go ahead and connect your SD card to the PC, and first, let’s make sure you don’t have a Scrappy already downloaded.
Go into MUOS/applications and if you see a Scrappy folder here, delete it. Fresh start.
Two SD card users should check both SD cards for this.
Then let’s grab the latest release from the Scrappy Github.
We want the muxapp that does not say update in the filename.
Download it and make sure to put that into the ARCHIVE folder on your SD card.
Safely eject, pop the SD card back into your device and turn it on.
Head to Applications and then Archive Manager.
Push A on Scrappy to install it.
Back in Applications, scroll down and now open Scrappy.
You can adjust what your scrape will look like, I like epic gradient so I’m going to use that.
Then you can choose what to scrape, it’s our first time so Scrape All.
Head down and into Advanced Tools, in the future you can Update Scrappy right from here.
Head back and push Select, and you want to enter your Screenscraper username and password or you’ll hit limits.
Just register on Screenscraper’s website and use those credentials here and push Save.
Scroll down and I would highly suggest you do one system at a time because scraping can take forever, so maybe un-check all and start with one system.
Push select to head back and now scroll up and click Start scraping to start.
