CrossMix OS: Installation Guide (Mac)

What is CrossMix OS?

CrossMix OS is a powerful, versatile custom firmware for retro handhelds. It combines the best elements from GarlicOS, MinUI, and others — all in a smooth and fast user interface, with wide compatibility and extra features.

It’s especially popular among TrimUI Smart Pro users, but it also runs on other devices like the Anbernic RG35XX.

Installation Guide for macOS

This guide is specifically written for Mac users. No terminal commands needed — just a MicroSD card, a reader, and a little patience.

What You’ll Need

• A MicroSD card (8GB minimum, 64GB or more recommended)
• An SD card reader or microSD adaptor
• The latest CrossMix OS release
• BIOS files (more on that later)
• Your ROM collection

Step 1: Format the SD Card via Finder (FAT32)

1. Insert the SD card into your Mac
   Use a card reader if your Mac doesn’t have a built-in slot.

2. Open Finder
   Locate the SD card in the sidebar.

3. Right-click the SD card and choose ‘Erase’
   In the window that appears:

   • Format: choose MS-DOS (FAT)
   • Name: for example, use CROSSMIX
   • Scheme: leave it as default

4. Click ‘Erase’ and wait for the formatting to complete
   This may take a few minutes depending on your card’s size and speed.

Step 2: Install CrossMix

1. Download the latest release
   Go to the CrossMix GitHub releases page
   Scroll to the bottom under “Assets” and download a ZIP file like:
   CrossMix-OS_v1.x.x.zip

2. Extract the ZIP file directly to your SD card
   Use Finder or an app like The Unarchiver (faster).
   Make sure you extract the contents directly to the root of your SD card.

Step 3: Add BIOS Files

Download the necessary BIOS files from this Retro Gear BIOS archive link.
Copy the correct files into the BIOS folder on your SD card.

*be aware… downloading bios and rom files is not always legal.

Tip: If you’ve used RetroArch before, you can copy BIOS files from
RetroArch/.retroarch/system.

Step 4: Add Your Games (ROMs)

Find ROMs online through the Retro Games Megathread
or explore the RG Collection on Archive.org.

*be aware… downloading bios and rom files is not always legal.

Unzip your ROM files and organize them into the correct subfolders on your SD card. For example:

• NES for Nintendo Entertainment System
• GBA for Game Boy Advance
• PSP for PlayStation Portable

Some folder names differ from the stock OS. A few examples:

• PPSSPP → PSP
• OPERA → PANASONIC
• PICO8 → PICO

Step 5: Boot CrossMix OS

Insert the SD card into your TrimUI Smart Pro and power it on.
The first boot may take a little longer — CrossMix is setting up PortMaster and other components.

Done!

You now have a clean and fresh install of CrossMix OS on your retro handheld. Enjoy the sleek UI, quick load times, and full system compatibility.

Did this guide help you out?

Let others know on Reddit, Discord, or social media! And if you’re in the market for modded Game Boys, handheld upgrades, or accessories — check out my shop: retrogear.nl

-XXX-

Jorne