Back with a major performance update to Retro Shaders!

A few weeks back u/MontyFrog shared a spectacular overlay collection in the sub. I had never seen this. I was only aware of shaders for pixel rendering. I had to investigate. (Check his overlays out they're awesome!)

As it turns out overlays can do a fantastic job of simulating pixel rendering without any of the overhead that comes with shaders. We get better visuals with almost no hit to performance. WHY WASN'T I ALREADY DOING THIS?????

Rather than complicate things bringing other artists work into the script I decided to improve my own game and keep the Retro Shaders overlays truthful to their historic counterparts. The goal is accurate recreation of the original bezels and screen effects - including ghosting. Keep it simple, nothing more.

The new overlays affect the following systems:

• Gameboy
• Gameboy Color
• Gameboy Advance
• Neo Geo Pocket
• Neo Geo Pocket Color

I think they turned out alright! The other handhelds are still using pixel shaders as that is the only way to get the BGR effect that was common with screens from that period.

If you find 80's CRT to be causing slowdown try the 90's Monitor setting instead as it's much lighter on resources.

Download:

Dave's Retro Shaders v1.7

This Retro Shaders update has already been included in dArkOSen, no need to update if you are using the latest image or update.

I reviewed the SD card guide and it says it can take red & grey ultras, but I don’t know if this will work

Well, some of you saw the post I made a while ago here, asking for port ideas, and undoubtedly the most commented on was Hollow Knight, which in turn already has a port on Portmaster, however, it only works on devices with 2GB of RAM or more, and with a 16:9 resolution; development of the port began some time ago, I call it the Hollow Knight Lite R36S Edition, although it's obviously not exclusive to the R36S, it aims to work satisfactorily on weaker devices and has an adaptation for 4:3 resolution. The other project is ArkBogs, which does seem somewhat out of place in this subreddit's topic, but I wanted to include it here for the sake of announcing the project. ArkBogs is a version of dArkOS for low-cost TV boxes, those with 1-2GB of RAM are also in early development; I'll update you on both projects in this subreddit.

Very few people talk about playing Java games on the R36S, and for good reason, since the RetroArch core is still pretty limited (I haven't tried any 3D games yet).

Even so, it's a pretty interesting experience. I recommend using the 320×240 builds of games—they look perfect on the handheld's screen. I'm still testing more games to see which ones work without major issues, but at least these three ran pretty well.

If you wanna try it yourself, just drop the .jar files into the j2me folder inside EASYROMS.

Sorry about the rough video quality and questionable editing. I recorded this pretty quickly because I was really excited about it.

Used a 3D printer to invert the button layout

https://reddit.com/link/1v3wmr1/video/fh1ashh44veh1/player

https://reddit.com/link/1v3wmr1/video/nh1mylg05veh1/player

https://reddit.com/link/1v3wmr1/video/44f93w325veh1/player

https://reddit.com/link/1v3wmr1/video/5v53t46o5veh1/player

https://reddit.com/link/1v3wmr1/video/aep5fatq5veh1/player

Hi!

After many hours of experimenting, I managed to get Ruffle running on the R36S with DarkOS. Personally I searched for it and i couldn't find a way to do it so i did it myself.

I don't consider this a proper "port" since Ruffle already provides official Linux ARM64 builds. What I really did was adapt it to work on the R36S by integrating the required libraries, creating launcher scripts, and making it work with the PortMaster runtime.

I also want to be transparent about the process: this project relied heavily on AI-assisted development. AI was incredibly useful for investigating logs, understanding Linux graphics issues, and exploring possible solutions. However, getting everything working still required a lot of manual testing, trial and error, and debugging directly on the device.

I'm sharing this because I'd love to see other people improve it if possible. I don't really care about credit I just want Flash games to become another playable platform on the R36S.

Requirements

• DarkOS
• Portmaster

Current status

• ✅ Official Ruffle ARM64 nightly works.
• ✅ GPU acceleration is working.
• ✅ Playable performance in games such as Fancy Pants.
• ✅ Controller support through gptokeyb.
• ⚠️ There is still a graphical issue: moving the mouse cursor (mapped to the right analog stick) causes screen flickering while the cursor is moving. When the cursor is stationary, the flickering stops.
• ⚠️ Because of this, point-and-click games may not provide the best experience yet, although it's perfectly usable for navigating menus in keyboard-focused games.

Folder layout

/roms/ports/
│
├── DadNMe.sh
├── FancyPants.sh
├── ...
└── ruffleEngine/
    ├── ruffle
    ├── libssl.so.1.1
    ├── libcrypto.so.1.1
    ├── (required libraries)
    └── games/
        ├── DadNMe/
        │   ├── dadnme.swf
        │   └── controles.gptk
        │
        ├── FancyPants/
        │   ├── fancypants.swf
        │   └── controles.gptk
        │
        └── ...

Each game has its own launcher script inside /roms/ports/.

The launcher only needs these variables to be changed:

CARPETA_JUEGO="DadNMe"
ARCHIVO_SWF="dadnme.swf"
ARCHIVO_GPTK="controles.gptk"

Each game's folder contains:

• the Flash (.swf) file
• a .gptk controller profile

The .gptk profile will likely need to be customized for each game, since Flash games don't share a common control scheme.

https://drive.google.com/file/d/1dpP34JznpMx-Zx8XOuTlnlXKHlMQi4bZ/view?usp=sharing

I spent the last few days testing Arch-R on my R36S. I originally switched because I had reached a dead end trying to push the old Linux 4.4 kernel in dArkOS any further.

My goal wasn't to compare distributions. I simply wanted a modern kernel to continue low-level hardware research.

Here are my observations so far.

What worked immediately:

- System booted normally after flashing.

- All core services came up without issues.

- USB OTG gadget works out of the box.

- Ethernet-over-USB works immediately.

- SSH over USB works immediately.

- Wi-Fi works.

- The battery indicator reports correct battery level.

- No speaker noise in the menus.

- No speaker noise after leaving games.

- No speaker noise while using my USB Wi-Fi dongle.

For me, USB Ethernet alone was a huge improvement. On dArkOS I spent a long time patching DTBs and experimenting with USB gadget mode before reaching the same point.

Things I noticed:

Wi-Fi SSH

After rebooting the console, SSH over Wi-Fi reports: WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

It is easy to fix by removing the old SSH host key from known_hosts, but it becomes annoying during development.

I haven't investigated the reason yet.

OTG role switching

Switching from USB Gadget mode to USB Host still requires rebooting or powering the console off.

Runtime role switching would still be preferable.

Package repository

The Arch-R repository intentionally contains only a relatively small set of packages.

For example, I tried installing Midnight Commander:

pacman -S mc

and discovered that the package is simply not available.

This isn't necessarily a problem, but developers coming from a traditional Arch Linux environment should be aware of it.

SanDisk SD cards in TF2

I immediately ran into the exact same TF2 problem I had previously solved in dArkOS.

Large SanDisk cards fail to initialize because of the MMC timing configuration.

The good news is that my previous DTB fix works on Arch-R without modification.

Repository:

https://github.com/khizhnik/r36s-ArchR-fixtures

PortMaster

One interesting difference compared to dArkOS:

PortMaster itself correctly detected all of my existing ports.

However, EmulationStation only displayed ports whose launcher scripts were located directly inside:

/storage/roms/ports

After copying the launcher .sh files to the top-level ports directory, every port immediately appeared and launched correctly.

So this seems to be an Arch-R frontend convention rather than a PortMaster problem.

Why I moved to Arch-R

The only reason I switched was the newer Linux kernel.

For people interested in kernel work, device trees, USB, drivers, or low-level hardware research, this alone is a huge advantage.

If your current operating system already does everything you need, I don't think there is a strong reason to migrate.

But if you enjoy exploring how these handhelds actually work internally, the newer kernel opens many interesting possibilities.

Overall impression

After only three days, I can already say that the overall architecture of Arch-R feels well designed.

This may surprise people who know that I'm not particularly fond of Arch Linux.

Even so, I think the project itself is technically impressive.

If someone ever decides to build a Debian or Ubuntu based operating system for the R36S with a clean and maintainable architecture, I would strongly recommend studying the solutions already implemented in Arch-R.

At the moment I'm running Arch-R from an 8 GB SD card while keeping my dArkOS installation intact.

My plan is to continue comparing both systems because I believe each of them can inspire improvements in the other.

Test hardware

Device:

R36S

PCB revision: R36S-V1.0

PCB date: 2024-09-27

SoC

Rockchip RK3326

RAM

1 GB (2 × Micron D9QWN DDR3)

Audio

RK817 PMIC / audio codec

External amplifier marked 20N52 (possibly JS2001 family, not yet confirmed)

I've searched for a solution but I've still not found any around so I'll ask again.
Even though its been asked before. Since all the previous posts I've found with this question. How do I make the cursor dissapear during normal game-play and re-appear when menus are open?

And also. I don't think this problem applies to any specific devices so I'll not provide a mainboard number here since I think its irrevelant to this discussion. Any fixes that could be done on device, USB(OTG) and/or with Remote Services would be greatly appreciated.Also if you really wanted to know at least I can tell you it is an R36 ULTRA. Don't see the mainboard number under the battery. Sorry.

I am trying to create a fork of dArkOSRE - https://github.com/southoz/dArkOSRE-R36 - and i want to know about how to build an image file myself after altering the fork's source code. I cant seem to find any information on this online, so if someone can help or point me in the right direction, it would be much appreciated.

https://x.com/i/status/2079145562289623111

What would happen if we were to replace the RK3226 on the R36S with this beast, leaving everything else the same? What would need to be recoded, and what do you think the performance would be?

Did all right (i guess), half life and undertale are working both perfectly but balatro doesent even open.

I putted the .exe in the balatro folder
I am using the latest port master version
My r36s is a clone but it has some version of arkos(I don’t know wich)

Tried renaming the file to just balatro or Balatro.exe but none work

What could i do?

I can't use the portmaster installer because it keeps saying that it doesn't have the permissions to create folders.

Also its trying to use roms2 even though I don't have a second SD card

I started testing Arch-R on my R36S and immediately ran into a familiar problem: my 512 GB SanDisk card was not detected in the second SD slot.

The kernel initialized the second MMC controller, but card startup failed with:

mmc0: error -110 whilst initialising SD card

I had previously encountered almost the same issue on dArkOS, so I compared the working DTB fix with the Arch-R device tree.

The minimal fix was:

- limit only mmc@ff380000 to 50 MHz;

- remove the UHS SDR12/25/50/104 capability flags;

- leave the system SD controller untouched.

After applying the patched DTB, the card initialized successfully:

- mmc0: new high speed SDXC card

- mmcblk0: mmc0:aaaa SK512 477 GiB

Tested on:

- R36S

- Arch-R 20260709

- Linux 6.12.94

- SanDisk 512 GB microSD

- TF2 slot

The repository includes the minimal patch, original/patched hashes, test report, and post-boot logs:

https://github.com/khizhnik/r36s-ArchR-fixtures

This may also help other cards or R36S board revisions that fail with mmc0 error -110, but so far I have only verified it on my own device and card. Back up your original DTB before testing.

Yep

I have the original panel 0 variant(r36s-v12, 2023)
With darkOS (latest and previous build), whenever I switch to sd2 and try to boot, it’ll get stuck on the loading screen.
Never had this issue with ArkOS builds. I am not sure what’s the issue, I am using a 128gb silicon power SD card in slot 2.

Hi everyone! Need some help with a sudden performance issue on my R36S.

Setup:

• Handheld: R36S
• Connection: Wi-Fi dongle via OTG cable (used for RetroAchievements)
• Game: Pokémon FireRed with the Professor Oak's Challenge patch (RA achievements enabled)

The Issue:

Everything was working flawlessly until recently. I opened the ROM and an old save on my PC just to test a few things. Immediately after, when I booted up my R36S:

1. RetroAchievements was logged out.
2. I logged back into RA and loaded the game.
3. The game now runs at an unplayable 5 to 10 FPS.

The Catch:

If I disable RetroAchievements (or disconnect from Wi-Fi), the game goes straight back to a locked 60 FPS / normal speed. The severe lag only happens when RA is active and connected.

What I've already tried:

• Fully formatted the console and re-flashed the OS.
• Used the same ROM and save file. Same lag.
• Re-synced the save file from the PC back to the R36S. Still lags.

Has anyone encountered this heavy lag caused by RetroAchievements on ArkOS / R36S before? Any ideas on how to fix it?

Thanks in advance!

This is 2004 .hack// phone game released in South Korea. Hopefully this game was translated to English (thanks to Tyrial and other DHN staff) and supported by FreeJ2ME. There is also native 3ds port made by Twilight Studios.

I want to buy an R36S from the Shenzhen Qbuy store on Alibaba.

I know this has been discussed many times, but I couldn't find a clear answer. Some people say they received a genuine device, while the wiki lists Shenzhen Qbuy as an untrusted seller.

If you've bought from them recently, could you share your experience?

1. Was the device genuine?

2. How was the overall experience?

3. Any issues with shipping or customs?

Also, since most people recommend replacing the included SD card anyway, is it okay to buy the version without an SD card and just flash a compatible OS onto my own microSD card? Will it work without any problems?

Lastly, I'm from India, and there isn't much up-to-date information about buying the R36S here. If enough people share their experiences, I'd like this post to become a useful reference for future buyers from India.

Maybe a dumb question, but how do you all handle battery charging?

I've read that the on-screen battery indicator isn't reliable, so whenever I hit 20-30% I plug it in to charge. But neither the battery animation on the display nor the red LED changes based on charge %, so I have no way to check how far along the charge actually is. Usually I just turn the R36S back on after about an hour and check the display to confirm it's at 100%.

Is there a faster/more reliable way to check charge status? How do you all usually do it?

Hey everyone,

Hit a bit of a bump with my R36S and I need to do a full restoration.

Does anyone happen to have 3D printable case models for the R36S, or know a good site where I can find them?

Also, I need to repair my OTG port, but I haven't been able to find a schematic anywhere. Does anyone know which traces/paths to follow or have a schematic they could share?

Any help is much appreciated, thanks!