RetroCompass
RetroCompass

RG28XX — Custom firmware

Quick answer

Button combo

POWER(boots whichever OS is on TF1)

Steps

  1. 1Pick a community OS for the H700: muOS, Knulli or MinUI (all publicly released; MinUI runs from its own card).
  2. 2Download the device-appropriate image from the project's official site/GitHub and unzip it.
  3. 3Flash the image to a spare TF1 (OS) microSD card with balenaEtcher.
  4. 4Keep your ROMs on TF2 (some firmwares want it formatted FAT32 or EXT4 — follow that project's guide).
  5. 5Insert the card in TF1, power on, and complete the firmware's first-run setup.
Last verified: 2026-06-20Source: anbernic.com

The RG28XX uses the Allwinner H700, so it can boot publicly released community operating systems by simply flashing them to the TF1 (OS) microSD card with balenaEtcher — the same swap-the-card method as the stock OS, with no modification to the device itself. Popular choices are muOS (fast, hotkey-driven), Knulli (Batocera/EmulationStation based) and MinUI (minimal, runs from its own card); your ROMs stay on the TF2 card. Note H700 community images generally target the 2GB-RAM RG28XX, not the 1GB model, so confirm your hardware, and always keep your original stock TF1 card so you can switch back. This is a DRAFT for human review.

FAQ

Do I have to modify the device to run custom firmware?
No. These are publicly released OS images that boot from the TF1 microSD card. You just flash a card with balenaEtcher and swap it in; keep the stock card to return to Anbernic OS.
Does custom firmware work on the 1GB RG28XX?
Community images such as muOS and Knulli generally target the 2GB-RAM RG28XX, not the 1GB version. Check your model and the project's compatibility notes before flashing.

Same device — other tasks

Other devices — same task