Iot: Development work on Windows 10

[alex182]

I am attempting to do development work on a Windows 10 machine for a project that will be used on a Raspberry Pi. The only issue I am running into is that when I attempt to run my project on the Windows 10 machine I get the following exception No GPIO controllers exist on this system..

Now I understand why that is happening (my laptop obviously doesn't have GPIO pins) but I was wondering if there was a built in way to suppress this error?

[krwq]

@alex182 do you mean i.e.:

using (var controller = new GpioController())
{
// what would you do with `controller`
}

? What would you do with such instance? Could you give some usage example?

[Frankenslag]

@alex182

I am not really answering your question, I know, but I am not sure why you want to execute on the Win10 machine. I have found it reasonably simple to publish the resultant code to a RaspberryPi and then debug using a combination of VS2019 and vsdbg on the Pi. (I guess you could use VSCode but I have not tried it).

This allows you to develop and debug using familiar tools if you are a Windows developer but also see the effects of manipulating Gpio, Spi, I2c etc.

[alex182]

@krwq I am developing an api that runs on the Pi but there are non-GPIO things that I want to be able to debug on my Windows 10 machine (logging, validation etc)

@Frankenslag I am doing that but the deploy takes about 5 minutes each time and I really dont want to be waiting for that when I am tweaking logging/validation

I guess what I am essentially asking is if there is a way to mock the controller somewhere on my Windows 10 machine?

[joperezr]

@alex182 Does your app do other things apart from just controlling the microcontroller? I suppose it does and then that is why you want to just mock that part so you can continue debugging the rest of your code. I'm not sure we have a good way of doing that, but I would suggest two things:

1. You could locally create a class that extends the GpioDriver which simply doesn't do anything, and then use that to initialize your GpioController. So adding a class that looks like this:
   ```c#
   class GpioDriverMock : GpioDriver
   {
   protected override int PinCount => 0;

   protected override void AddCallbackForPinValueChangedEvent(int pinNumber, PinEventTypes eventTypes, PinChangeEventHandler callback) { }

   protected override void ClosePin(int pinNumber) { }

   protected override int ConvertPinNumberToLogicalNumberingScheme(int pinNumber) => 0;

   protected override PinMode GetPinMode(int pinNumber) => default(PinMode);

   protected override bool IsPinModeSupported(int pinNumber, PinMode mode) => true;

   protected override void OpenPin(int pinNumber) { }

   protected override PinValue Read(int pinNumber) => default(PinValue);

   protected override void RemoveCallbackForPinValueChangedEvent(int pinNumber, PinChangeEventHandler callback) { }

   protected override void SetPinMode(int pinNumber, PinMode mode) { }

   protected override WaitForEventResult WaitForEvent(int pinNumber, PinEventTypes eventTypes, CancellationToken cancellationToken) => default(WaitForEventResult);

   protected override void Write(int pinNumber, PinValue value) { }
   }

And then you could just add this to use this mock when creating your controller:

```c#
using (GpioController controller = new GpioController(PinNumberingScheme.Logical, new GpioDriverMock()))
{
  // Do whatever with your controller.
}

Once you are ready to test in in actual hardware, simply remove the parameters passed in to new GpioController().

1. The other option would be to just add a try catch to the places where you are hitting the exception, and simply remove them whenever you are ready to deploy.

[alex182]

@joperezr thats exactly what I was looking for. And yes the app does more than accessing the micro controller. Thank you.

[joperezr]

Cool, closing for now, feel free to reopen if you need any additional help.