Deploying to a Raspberry Pi

As of version 5.0 you can now export console apps to Linux, which makes the Raspberry Pi an excellent target.

Prerequisites

Useful NuGets

  • System.Device.Gpio: for GPIO, I2C, SPI, PWM, Serial port
  • Iot.Device.Bindings: for higher-level specific device support
  • VL.IO.RCP for remote controlling parameters of the application from a web browser
  • Any of the libraries in the IO category
  • SFML.Net: for audio playback and recording (NOTE: version 2.5.0 of the NuGet has audio recording broken. Compile yourself from sources to get this working)

Deployment

In the Application Exporter specify:

  • Output type: Console Application
  • Target: Linux

This builds the program locally on your Windows PC. But now you want to copy the build artefacts to the Pi in order to run the program there. To automate this copy process, press Advanced build configuration and add the following lines inside the <Project> tag:

<PropertyGroup>    
  <SourceFolder>PATH-TO-YOUR-PROJECTS-EXPORT-FOLDER</SourceFolder>
  <DestFolder>PATH-TO-YOUR-DESTINATION-FOLDER-ON-THE-PI</DestFolder>
</PropertyGroup>

<ItemGroup>
  <FilesToCopy Include="$(SourceFolder)\**" />
</ItemGroup>

<Target Name="Deploy" AfterTargets="Publish">
  <!-- copy all files from the source folder to the dest folder that are newer or don't exist in the dest folder -->
  <Message Importance="High" Text="Copying files to Raspberry PI..." />
  <Copy SourceFiles="@(FilesToCopy)" DestinationFiles="@(FilesToCopy->'$(DestFolder)\%(RecursiveDir)%(Filename)%(Extension)')" SkipUnchangedFiles="True">
    <Output TaskParameter="CopiedFiles" ItemName="Copied" />
  </Copy>
    
  <ItemGroup>
    <OutdatedFiles Include="$(DestFolder)\**" Exclude="@(Copied)" />
  </ItemGroup>
  <Message Importance="High" Text="Deleting files..." />
  <Delete Files="@(OutdatedFiles)" />
</Target>

After a successful export head over to a commandline on the PI and run the program by typing:

dotnet myprogram.dll

Autostart

To have your application autostart when starting the Pi, you need to install it as a service (other options like rc.local or a .desktop file don't seem to work).

For installing a service, refer to chapter "4.4 Using A Systemd Service" of boot.pdf.

Pitfalls

  • If your program is accessing files, make sure to set the WorkingDirectory to where your application resides on disk
  • ExecStart needs to have absolut paths to both "dotnet" and your application. eg.: /home/pi/.dotnet/dotnet /home/pi/MyApp/myapp.dll