RetrOS – Custom Firmware for Clone R36S (rk3326 Variant)

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** NOT FOR "REAL" R36S CONSOLES **

** INTERNAL FIRMWARE VARIANTS WITH TF1 HIGHEST SUPPORT **

** BRAND NEW DEVELOPMENT. PATIENCE PLEASE. **

** PROBLEM? FILE AN ISSUE **

Welcome to RetrOS – a clean, stable custom firmware for clone Temu R36S handhelds powered by the RK3326 SoC. RetrOS is purpose-built to boot from TF1, restoring and enhancing factory behavior with modern tweaks, deeper hardware support, and full image portability.

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🚀 What’s Inside RetrOS

RetrOS is based on a hybrid build from factory NAND firmware, fused with stable bootloader components from K36 Clean. It combines:

• ✅ More Themes Sourcing themes stinks, more built right in!
• ✅ MBR from K36 Clean — ensuring reliable boots on any card size
• ✅ Custom kernel + DTB for R36S (rk3536 variant) with correct analog stick mapping
• ✅ Direct NAND extraction of factory system partition
• ✅ Fixed splash screen support (logo_kernel + system splash)
• ✅ Support for USB, WiFi (depending on module), and SSH
• ✅ Re-enabled EmulationStation features like Collections, Ports, and Netplay
• ✅ Mount SWAP Partition on MMC Automatically mounts mmcblk0p4 on internal EmuElec Clones

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🔧 Technical Overview

• Boot: Clean extlinux.conf-based U-Boot setup with optional UUID or device path booting (/dev/mmcblk1pX)
• Kernel: Pulled from NAND image for perfect analog stick support; later builds will include modular kernel support
• DTB: Uses rf3536k3ka.dtb, which fixes analog direction and input registration
• System: Based on clean EmuELEC 4.x series with modified init and terminal utilities
• Splash: Boots with logo_kernel.bmp and optional plymouth-like splash image (neon gamepad design included)

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🛠 Use Cases

• 🧪 Reverse engineering: Full NAND mirror used for analysis
• 💾 System restoration: Reflashable image with correct bootloader
• 🎮 Custom OS base: Great for modders and retro gaming OS devs
• 💡 Reference firmware: Use RetrOS as a clean baseline for custom EmuELEC builds

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⚠️ Known Issues

• ⏱️ Boot is slightly slower (~30s) using factory kernel; WIP kernel builds may improve this
• 🔌 WiFi support depends on compatible USB dongle or onboard chip (not all are supported)
• 🛠️ Recovery tools are not included by default; mount the STORAGE partition externally to debug

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🧠 Coming Soon

• Automatic resizer for STORAGE on first boot
• Built-in busybox terminal launcher (for low-level debugging)
• Optional RetroArch core updater integration
• RetrOS OTA build script for kernel patching + image generation
• More Unlock and Utility Apps
• Update and Standalones and Cores for Offline
• Verify all compatible Wifi Dongles
• Port Master

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📂 Credits

• AeolusUX
• EmuELEC community
• K36 Clean for bootloader base
• RetrOS contributors for tooling, splash graphics, and testing
• Pyntux for rf3536k4ka.dtb