PowerMate 0.0.1-SNAPSHOT2

Receive events from a Griffin PowerMate device over USB

1. Quick Start
2. Prerequisites
3. Installation
4. Usage
   • Connections
5. Events
   • InputReceived
   • IsConnectedChanged
6. Limitations
7. Acknowledgements

Quick Start

dotnet install PowerMate

using PowerMate;

using IPowerMateClient powerMate = new PowerMateClient();

powerMate.InputReceived += (sender, input) => {
    switch (input) {
        case { IsPressed: true, IsRotationClockwise: null }:
            Console.WriteLine("PowerMate was pressed");
            break;
        case { IsPressed: false, IsRotationClockwise: true }:
            Console.WriteLine("PowerMate was rotated clockwise");
            break;
        case { IsPressed: false, IsRotationClockwise: false }:
            Console.WriteLine("PowerMate was rotated counterclockwise");
            break;
        default:
            break;
    }
};

Prerequisites

• A Griffin PowerMate
  • ✅ The USB version is supported
  • ❌ The Bluetooth version is not supported
• Any Microsoft .NET runtime that supports .NET Standard 2.0 or later
  • .NET 5.0 or later
  • .NET Core 2.0 or later
  • .NET Framework 4.6.1 or later
• A supported operating system
  • ✅ Windows (verified on 10 22H2 and 11 22H2)
  • ✅ MacOS (verified on 12.6)
  • ❓ Linux is currently unverified

Installation

You can install this library into your project from NuGet Gallery:

• dotnet add package PowerMate
• Install-Package PowerMate
• Go to Project › Manage NuGet Packages in Visual Studio and search for PowerMate

Usage

1. Construct a new instance of the PowerMateClient class.

   using IPowerMateClient powerMate = new PowerMateClient();
   

   You should dispose of instances when you're done with them by calling Dispose(), or with a using statement or declaration.

2. Now you can listen for InputReceived events from the client.

   powerMate.InputReceived += (sender, input) => Console.WriteLine($"Received PowerMate event: {input}");
   

Connections

This library will automatically try to connect to one of the PowerMate devices that are plugged into your computer. If no device is connected, it will automatically wait until one appears and then connect to it. If a device disconnects, this library will reconnect automatically when one reappears.

If multiple PowerMate devices are present simultaneously, this library will pick one of them arbitrarily and use it until it disconnects.

The connection state is exposed by the bool IsConnected property, and changes to this state are emitted by the IsConnectedChanged event.

Console.WriteLine(powerMate.IsConnected 
    ? "Listening for movements from PowerMate." 
    : "Waiting for a PowerMate to be connected.");

powerMate.IsConnectedChanged += (_, isConnected) => Console.WriteLine(isConnected 
    ? "Reconnected to a PowerMate." 
    : "Disconnected from the PowerMate, attempting reconnection...");

Events

InputReceived

Fired whenever the PowerMate knob is rotated, pressed, or released.

The event argument is a PowerMateInput struct with the following fields.

IsConnectedChanged

Fired whenever the connection state of the PowerMate changes. Not fired when constructing or disposing the PowerMateClient instance.

The event argument is a bool which is true when a PowerMate has reconnected, or false when it has disconnected.

To get the value of this state at any time, read the IsConnected property on the IPowerMateClient instance.

Limitations

• This library currently does not allow you to change the LED brightness.
• This library does not connect to Bluetooth PowerMates.

Acknowledgements

• Luke Ma for giving me a PowerMate as a Christmas gift in 2013