RT-950 UPDATE - Cross-platform Version

Firmware update application for the RT-950 radio, ported from Windows Forms to Avalonia to run on macOS, Linux, and Windows.

Features

• ✅ Cross-platform GUI with Avalonia
• ✅ Support for macOS (Apple Silicon and Intel)
• ✅ Support for Linux and Windows
• ✅ Modern async/await instead of Thread.Abort()
• ✅ Native serial port handling using POSIX termios on macOS/Linux
• ✅ Automatic serial port detection with smart filtering
• ✅ Virtual port support for serial debugging (/tmp/vmodem0)
• ✅ Optimized for macOS: prefers /dev/cu.* over /dev/tty.* ports
• ✅ Same communication protocol as the original version
• ✅ Built-in mode instructions in the UI
• ✅ Clean cancellation support with CancellationToken

Requirements

• .NET 9.0 SDK
• USB serial port (RT-950 radio connected)

Build

dotnet build

Run

dotnet run

Create Standalone Executable

For macOS (Apple Silicon):

dotnet publish -c Release -r osx-arm64 --self-contained

For macOS (Intel):

dotnet publish -c Release -r osx-x64 --self-contained

For Linux x64:

dotnet publish -c Release -r linux-x64 --self-contained

For Windows x64:

dotnet publish -c Release -r win-x64 --self-contained

The executable will be in bin/Release/net9.0/{runtime}/publish/

Usage

1. Connect your RT-950 radio to a USB port
2. Run the application
3. Click "..." to select a .BTF firmware file
4. Select the COM port from the dropdown list
   • On macOS, ports marked "(recommended)" are preferred
   • If using serial mirroring, select the port marked "(MIRROR - use this!)"
5. Choose the update mode:
   • Upgrade Mode (green): Radio powered on normally
   • Flashing Mode (red): Radio in bootloader mode (power off, hold side keys 3+4, power on)
6. Wait for the update to complete

Architecture

RT950Update/
├── Core/
│   ├── BootHelper.cs      - Communication and update logic
│   ├── PackageFmt.cs      - Protocol packaging
│   ├── NativeSerial.cs    - Native POSIX serial port handling
│   └── STATE.cs           - Process states
├── ViewModels/
│   ├── MainWindowViewModel.cs - UI logic
│   └── RelayCommand.cs    - Command implementation
└── Views/
    └── MainWindow.axaml   - Graphical interface

Differences from Original Version

• Uses async/await instead of blocking threads
• CancellationToken for clean cancellation
• ReactiveUI for MVVM pattern
• Native serial port handling on macOS/Linux via P/Invoke
• Cross-platform: macOS, Linux, and Windows
• .NET 9.0 instead of .NET Framework 2.0
• Smart serial port detection and filtering
• Support for virtual serial ports (debugging)

Technical Notes

The communication protocol is identical to the original:

• Baudrate: 115200
• Data bits: 8
• Stop bits: 1
• Parity: None
• Proprietary protocol with CRC-16/CCITT

Serial Port Implementation

On macOS/Linux, the application uses native POSIX termios via P/Invoke for reliable serial communication in RAW mode. This bypasses .NET's SerialPort limitations on these platforms and ensures proper hardware flow control.

On macOS specifically:

• /dev/cu.* ports are preferred over /dev/tty.* for callout devices
• The application automatically marks recommended ports in the dropdown
• Virtual port /tmp/vmodem0 is detected for serial port mirroring/debugging