R36 Control Centre

R36 LED & Config Service for dArkOS RE

Customisable Battery Warning LEDs + Hardware Detection for R36S / Clones / Soy Sauce

This service solves the biggest pain point for RK3326 R36S-style handhelds on dArkOS RE:

Different mainboards use different GPIO pins for status LEDs (or PMIC control), and many DTBs define these GPIOs → causing conflicts or no LED control in userspace.

The solution:

• Remove LED / battery / charger GPIO definitions from DTB nodes (or override them) so userspace owns the LEDs.
• Early-boot script (r36_config.sh) detects hardware via /proc/cpuinfo.
• Selects the correct battery warning Python script from /usr/local/bin/r36_config/batt_life_warning/.
• Persists settings in /etc/r36_config.ini.
• Provides a friendly R36 Control menu (under Options) to change LED behaviour, gamma, audio path, boot volume, etc.

Goal: Support R36 variants — genuine R36S (PMIC LEDs), Soy Sauce (Y3506), clones (G80C / G80CA / etc.) — without breaking DTB compatibility for screen / other hardware.

Features (v1.0)

• Automatic hardware detection & LED script selection on first boot/hardware change
• Safe override: LED control moved to Python scripts (no DTB GPIO conflict)
• Gamma correction persistence (Soy Sauce often oversaturated, clones under-saturated)
• ALSA Playback Path (SPK_HP vs SPK) + optional persistent boot volume
• User-friendly R36 Control menu:
  • Choose LED warning style (Blue/Purple/Red, Off variants, etc.)
  • Adjust gamma (0.4–1.8, live preview hint)
  • Toggle audio routing & set/clear boot volume
  • View/delete config (reset to defaults on reboot)
• Logging to /boot/darkosre_device.log
• Updated DTBs included (UHS removed from Soy Sauce for max compatibility)

How It Works

1. Early boot (r36-config.service → r36_config.sh):

   • Reads Hardware string from /proc/cpuinfo
   • Looks up variant in /boot/dtb/r36_devices.ini
   • If no /etc/r36_config.ini or hardware changed → creates config + selects matching LED script
   • Applies gamma, ALSA path, default 80% volume (only on first boot/change)
   • Symlinks correct batt_life_warning.py

2. Battery warning (batt_led.service):

   • Runs the selected Python script
   • Monitors battery → controls LEDs via sysfs (/sys/class/leds/ or exported GPIOs)
   • Different scripts for each variant (colour/thresholds)

3. User changes via R36 Control menu:

   • Overrides script, gamma, audio path/volume
   • Persisted in config.ini

Installation

(Assumes you're on dArkOS RE from southoz repos)

1. Update your image or copy files manually:

   • /usr/local/bin/r36_config.sh
   • /usr/local/bin/r36_config/batt_life_warning/ (all .py scripts)
   • /etc/r36_config.ini (created automatically)
   • /boot/dtb/r36_devices.ini
   • Systemd service: /etc/systemd/system/r36-config.service
   • Menu integration for "R36 Control" under Options

2. DTB preparation (critical for clones/Soy Sauce):

   • Use the updated DTBs included (or from your repo)
   • Ensure LED/charger/battery GPIO nodes are removed or disabled in the DTB → otherwise DTB fights userspace → LEDs may not work or conflict

3. Reboot → service runs → config created → LEDs should work.

Using R36 Control Centre

Launch from EmulationStation → Options → R36 Control

Main options:

• Select Battery LED Warning Type
  Pick script matching your variant (filtered for known devices; full list for unknown)

• Adjust Gamma Correction
  0.4–1.8 range. Changes apply on reboot.
  Tip: Hold R3 + D-Pad Left/Right for live preview (if gamma tool supports it)

• Audio Controls

  • Playback Path: SPK_HP (jack detection) or SPK (speaker only)
  • Boot Volume: Set fixed % or Clear to regain manual control

• Utilities

  • View current config
  • Delete config (resets to defaults on reboot)

Available LED Scripts when the system is on

File	Fully Charged	🔌	🔋	🔋	🔋
Clone_Blue_30_Purple_10_Red.py	TBA	🔴	>30% 🔵	>10% Purple	<=10% 🔴
Clone_Off_30_Purple_10_Red.py	TBA	🔴	>30% Off	>10% Purple	<=10% 🔴
Clone_Off_10_Red.py	TBA	🔴		>10% Off	<=10% 🔴
Clone_PMIC_Controlled.py	TBA	🔴
SoySauce_Blue_30_Pink_10_Red.py	TBA	🔴	>30% 🔵	>10% Pink	<=10% 🔴
SoySauce_Off_30_Pink_10_Red .py	TBA	🔴	>30% Off	>10% Pink	<=10% 🔴
SoySauce_Off_10_Red.py	TBA	🔴		>10% Off	<=10% 🔴
SoySauce_PMIC_Controlled.py	TBA	🔴
R36S_Green_30_Red.py	TBA	Orange		>30% 🟢🔵	<=30% 🔴
R36S_Green_20_Red.py	TBA	Orange		>20% 🟢🔵	<=20% 🔴
R36S_Green_10_Red.py	TBA	Orange		>10% 🟢🔵	<=10% 🔴
R36S_PMIC_Controlled.py	TBA	🔴

Important Notes & Warnings

• Genuine R36S often use PMIC-controlled LEDs (Green/Orange) → limited userspace control. Scripts focus on Red warning.
• Soy Sauce DTBs have UHS removed from SD card → better compatibility (no speed loss — see linked test).
• Audio init issues on some V12 clones → may need sleep/wake cycle (handled in some ogage binaries).
• If LEDs don't work → check DTB has no conflicting GPIO definitions.
• Unknown hardware → defaults to clone-like behavior + full script list.
• Logs: /boot/darkosre_device.log

Contributing / Testing

Untested boards welcome!
Report:

• Motherboard string (cat /proc/cpuinfo | grep Hardware)
• Which LED script works best
• Any GPIO / DTB conflicts

Pull requests for new scripts, DTB tweaks, or ini entries are appreciated.

Thanks to testers: 66dude, darrynmelck, Ace007186 (Discord), and the broader R36S community.