Rademacher DuoFern Integration for Home Assistant

A custom Home Assistant integration for Rademacher DuoFern roller shutters via the DuoFern USB stick (model 7000). If anyone has model 9000 please let me know if you experience troubles.

This integration communicates directly with the DuoFern USB stick using the native serial protocol — no cloud, no additional gateway, fully local.

Supported Devices

Device Type	Code	Description
RolloTron Standard	0x40	Roller shutter actuator
RolloTron Comfort	0x41	Roller shutter actuator (comfort)
RolloTron Pro	0x42	Roller shutter actuator (pro)
Additional types	0x47, 0x49, 0x4B, 0x4C, 0x4E, 0x61, 0x70	Various shutter actuators

USB Stick: Rademacher DuoFern USB-Stick (VID: 0x0403, PID: 0x6001)

Features

• Open / Close / Stop / Set Position for roller shutters
• Real-time position reporting (push-based, no polling)
• USB auto-discovery
• Config flow with 2-step setup (connection + device registration)
• Options flow for adding/removing devices after setup
• Standalone CLI tools for testing and device pairing

Installation

HACS (Recommended)

1. Open HACS (HomeAssistant Custom Solution) in Home Assistant
2. Click the three dots menu (top right) and select Custom repositories
3. Add https://github.com/MSchenkl/homeassistant-duofern with category Integration
4. Search for "Rademacher DuoFern" and install
5. Restart Home Assistant

Manual Installation

1. Copy the custom_components/duofern/ folder to your Home Assistant config directory:

   /config/custom_components/duofern/
   

2. Restart Home Assistant

Configuration

Step 1: Connection

Go to Settings > Devices & Services > Add Integration > DuoFern

• Serial Port: Select your DuoFern USB stick (e.g., /dev/ttyUSB0)
• System Code: The 6-digit hex code of your USB stick (starts with 6F, e.g., 6F1A2B). This is the dongle serial number, found in your previous FHEM config or on the stick itself.

Step 2: Paired Devices

Enter the 6-digit hex codes of your paired DuoFern devices, separated by commas:

e.g. 406B2D, 4090AE, 40B690, 

These are the device codes from your previous FHEM configuration.

Managing Devices After Setup

Go to Settings > Devices & Services > DuoFern > Configure to add or remove device codes at any time. The integration will reload automatically.

CLI Tools

The tools/ directory contains standalone Python scripts for testing and device management without Home Assistant.

Requirements

pip install pyserial pyserial-asyncio-fast

HAOS (Home Assistant OS) Note: On HAOS the system Python is externally managed. You need to run:

apk add py3-pip
pip install --break-system-packages pyserial-asyncio-fast

This is only needed for the CLI tools. The integration itself installs dependencies automatically via manifest.json.

test_duofern.py — Test Script

Control roller shutters directly from the command line:

python3 tools/test_duofern.py 4053B8 up           # Open one shutter
python3 tools/test_duofern.py 4053B8 down          # Close one shutter
python3 tools/test_duofern.py 4053B8 stop          # Stop one shutter
python3 tools/test_duofern.py 4053B8 position 50   # Set one to 50%
python3 tools/test_duofern.py 4053B8 status        # Status of one device
python3 tools/test_duofern.py up                   # Open ALL shutters
python3 tools/test_duofern.py down                 # Close ALL shutters
python3 tools/test_duofern.py position 50          # Set ALL to 50%
python3 tools/test_duofern.py status               # Status of ALL devices
python3 tools/test_duofern.py statusall            # Broadcast status request

pair_duofern.py — Pairing Tool

Pair and unpair DuoFern devices without FHEM:

python3 tools/pair_duofern.py pair              # Start pairing (60s window)
python3 tools/pair_duofern.py unpair            # Start unpairing
python3 tools/pair_duofern.py list              # List all devices with status
python3 tools/pair_duofern.py pair --timeout 120 -v  # Extended timeout + debug

Important: The HA integration must be disabled while using CLI tools, as only one process can access the serial port at a time.

Protocol

This integration implements the DuoFern serial protocol from scratch:

• Frame format: Fixed 22-byte (44 hex char) frames over UART at 115200 baud
• Init sequence: 7-step handshake (Init1, Init2, SetDongle, Init3, SetPairs, InitEnd, StatusBroadcast)
• ACK-gated send queue: One command in-flight at a time with 5-second timeout
• Push-based status: Devices report status changes proactively
• Position convention: DuoFern uses 0=open/100=closed, Home Assistant uses 0=closed/100=open (converted transparently)

Protocol implementation based on analysis of FHEM modules 10_DUOFERNSTICK.pm and 30_DUOFERN.pm.

Migrating from other Environments

1. Note your system code and device codes from your old configuration
2. Install this integration and enter the codes during setup
3. Device pairing is preserved in the USB stick — no re-pairing needed
4. For new devices, you can always use pair_duofern.py

License

MIT License - see LICENSE for details.