lego-bluetooth-experiments

A collection of projects to interface with Powered Up smart hubs.

The BluetoothController project is the low level library that interfaces with the bluetooth device. This is the main project in this repo.
The BluetoothLibraryTester project is a scratchpad with some samples of how to use the library.
The LegoBluetoothController.UI project shows how to use the library in a WPF application.

The following is a simple example of using the library. To use it, simply run the program, then power on a hub.

class Program
{
    static BluetoothLowEnergyAdapter _adapter;
    static HubController _controller;

    static async Task Main(string[] args)
    {
        _adapter = new BluetoothLowEnergyAdapter(HandleDiscover, HandleConnect, HandleNotification);
        Console.WriteLine("Searching for devices...");
        _adapter.StartBleDeviceWatcher();

        while (_controller == null)
        {
            await Task.Delay(100);
        }

        await _controller.ExecuteCommandAsync(new HubNameCommand());
        await Task.Delay(1000);
        await _controller.ExecuteCommandAsync(new ShutdownCommand());
    }

    static async Task HandleNotification(HubController controller, string message)
    {
        Console.WriteLine($"{controller.HubType}: {message}");
        await Task.CompletedTask;
    }

    static async Task HandleDiscover(DiscoveredDevice device)
    {
        Console.WriteLine($"Discovered device: {device.Name}");
        await Task.CompletedTask;
    }

    static async Task HandleConnect(HubController controller, string errorMessage)
    {
        if (controller != null)
        {
            _controller = controller;

            Console.WriteLine($"Connected device: {Enum.GetName(typeof(HubType), controller.HubType)}");

            await Task.CompletedTask;
        }
        else
        {
            Console.WriteLine($"Failed to connect: {errorMessage}");
        }
    }
}

There are two mechanisms for reading sensor data, the HandleNotification callback that is registered when creating the BluetoothLowEnergyAdapter, and any EventHandlers that are added for the IHubController. The following is a sample for enabling tilt sensor data:

static async Task Main(string[] args)
{
    var adapter = new BluetoothLowEnergyAdapter(HandleDiscover, HandleConnect, HandleNotification, HandleDisconnect);
    ...
    var port = controller.GetPortIdsByDeviceType(IOTypes.TiltSensor).First();
    await controller.ExecuteCommandAsync(new ToggleNotificationsCommand(port, true, "01"));
    controller.AddEventHandler(new TiltEventHandler());
}

static async Task HandleNotification(IHubController controller, string message)
{
    Console.WriteLine($"{controller.Hub.HubType}: {message}");
    await Task.CompletedTask;
}

Credits

I used the sharpbrick/powered-up github project as an example of how to use the Windows bluetooth libraries. I leveraged the work of the JorgePe/BOOSTreveng github project to figure out the messaging protocol before Lego released official documentation.

Note: This project is not associated with or supported by The LEGO Group in any way.

nateswartz/lego-bluetooth-experiments

lego-bluetooth-experiments

Credits