/// <summary>
/// Initializes a new instance of the <see cref="Windows10SpiDevice"/> class that will use the specified settings to communicate with the SPI device.
/// </summary>
/// <param name="settings">
/// The connection settings of a device on a SPI bus.
/// </param>
public Windows10SpiDevice(SpiConnectionSettings settings)
{
if (settings.DataFlow != DataFlow.MsbFirst || settings.ChipSelectLineActiveState != PinValue.Low)
{
throw new PlatformNotSupportedException($"Changing {nameof(settings.DataFlow)} or {nameof(settings.ChipSelectLineActiveState)} options is not supported on the current platform.");
}
_settings = settings;
var winSettings = new WinSpi.SpiConnectionSettings(_settings.ChipSelectLine)
{
Mode = ToWinMode(settings.Mode),
DataBitLength = settings.DataBitLength,
ClockFrequency = settings.ClockFrequency,
};
string busFriendlyName = $"SPI{settings.BusId}";
string deviceSelector = WinSpi.SpiDevice.GetDeviceSelector(busFriendlyName);
DeviceInformationCollection deviceInformationCollection = DeviceInformation.FindAllAsync(deviceSelector).WaitForCompletion();
if (deviceInformationCollection.Count == 0)
{
throw new ArgumentException($"No SPI device exists for bus ID {settings.BusId}.", $"{nameof(settings)}.{nameof(settings.BusId)}");
}
_winDevice = WinSpi.SpiDevice.FromIdAsync(deviceInformationCollection[0].Id, winSettings).WaitForCompletion();
}
private static SpiDevice CreateWindows10SpiDevice(SpiConnectionSettings settings)
{
// If we land in this method it means the console application is running on Windows and targetting net5.0 (without specifying Windows platform)
// In order to call WinRT code in net5.0 it is required for the application to target the specific platform
// so we throw the bellow exception with a detailed message in order to instruct the consumer on how to move forward.
throw new PlatformNotSupportedException(CommonHelpers.GetFormattedWindowsPlatformTargetingErrorMessage(nameof(SpiDevice)));
}
private static SpiDevice CreateWindows10SpiDevice(SpiConnectionSettings settings)
{
// This wrapper is needed to prevent Mono from loading Windows10SpiDevice
// which causes all fields to be loaded - one of such fields is WinRT type which does not
// exist on Linux which causes TypeLoadException.
// Using NoInlining and no explicit type prevents this from happening.
return(new Windows10SpiDevice(settings));
}
internal SpiConnectionSettings(SpiConnectionSettings other)
{
BusId = other.BusId;
ChipSelectLine = other.ChipSelectLine;
Mode = other.Mode;
DataBitLength = other.DataBitLength;
ClockFrequency = other.ClockFrequency;
DataFlow = other.DataFlow;
ChipSelectLineActiveState = other.ChipSelectLineActiveState;
}
/// <summary>
/// Creates a communications channel to a device on a SPI bus running on the current hardware
/// </summary>
/// <param name="settings">The connection settings of a device on a SPI bus.</param>
/// <returns>A communications channel to a device on a SPI bus running on Windows 10 IoT.</returns>
public static SpiDevice Create(SpiConnectionSettings settings)
{
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
{
return(CreateWindows10SpiDevice(settings));
}
else
{
return(new UnixSpiDevice(settings));
}
}
/// <summary>
/// Initializes a new instance of the <see cref="Windows10SpiDevice"/> class that will use the specified settings to communicate with the SPI device.
/// </summary>
/// <param name="settings">
/// The connection settings of a device on a SPI bus.
/// </param>
public Windows10SpiDevice(SpiConnectionSettings settings)
{
if (settings.ChipSelectLineActiveState != PinValue.Low)
{
throw new PlatformNotSupportedException($"Changing{nameof(settings.ChipSelectLineActiveState)} options is not supported on the current platform.");
}
if (settings.DataFlow == DataFlow.LsbFirst)
{
_isInverted = true;
}
_settings = settings;
// -1 means ignore Chip Select Line
int chipSelectLine = _settings.ChipSelectLine == -1 ? 0 : _settings.ChipSelectLine;
var winSettings = new WinSpi.SpiConnectionSettings(chipSelectLine)
{
Mode = ToWinMode(settings.Mode),
DataBitLength = settings.DataBitLength,
ClockFrequency = settings.ClockFrequency,
};
string busFriendlyName = $"SPI{settings.BusId}";
string deviceSelector = WinSpi.SpiDevice.GetDeviceSelector(busFriendlyName);
DeviceInformationCollection?deviceInformationCollection = DeviceInformation.FindAllAsync(deviceSelector).WaitForCompletion();
if (deviceInformationCollection is null || deviceInformationCollection.Count == 0)
{
throw new ArgumentException($"No SPI device exists for bus ID {settings.BusId}.", $"{nameof(settings)}.{nameof(settings.BusId)}");
}
WinSpi.SpiDevice?winDevice = WinSpi.SpiDevice.FromIdAsync(deviceInformationCollection[0].Id, winSettings).WaitForCompletion();
if (winDevice is null)
{
throw new Exception("A SPI device could not be found.");
}
_winDevice = winDevice;
}
/// <summary>
/// Initializes a new instance of the <see cref="UnixSpiDevice"/> class that will use the specified settings to communicate with the SPI device.
/// </summary>
/// <param name="settings">
/// The connection settings of a device on a SPI bus.
/// </param>
public UnixSpiDevice(SpiConnectionSettings settings)
{
_settings = settings;
DevicePath = DefaultDevicePath;
}
