SpiConnectionSettings Clase

Definición

Espacio de nombres:

Windows.Devices.Spi

Representa la configuración de la conexión con un SpiDevice.

public ref class SpiConnectionSettings sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Devices.DevicesLowLevelContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Activatable(Windows.Devices.Spi.ISpiConnectionSettingsFactory, 65536, "Windows.Devices.DevicesLowLevelContract")]
class SpiConnectionSettings final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Devices.DevicesLowLevelContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Activatable(typeof(Windows.Devices.Spi.ISpiConnectionSettingsFactory), 65536, "Windows.Devices.DevicesLowLevelContract")]
public sealed class SpiConnectionSettings

function SpiConnectionSettings(chipSelectLine)

Public NotInheritable Class SpiConnectionSettings

Herencia

Object Platform::Object IInspectable SpiConnectionSettings

Atributos

ActivatableAttribute ContractVersionAttribute MarshalingBehaviorAttribute

Requisitos de Windows

Familia de dispositivos	Windows IoT Extension SDK (se introdujo en la versión 10.0.10240.0)
API contract	Windows.Devices.DevicesLowLevelContract (se introdujo en la versión v1.0)

Ejemplos

En el ejemplo siguiente se muestra la funcionalidad básica de esta y otras API SPI mostrando cómo abrir un bus SPI por nombre descriptivo mediante la configuración de conexión predeterminada.

// Arduino SPIDigialPot example: http://arduino.cc/en/Tutorial/SPIDigitalPot 
// using digital potentiometer AD5206 the 50kohm variance 
async void Digipot_AD5206() 
{ 
    // Get a device selector query that will select buses with SP10 
    // property set on them (we expect only 1 SP10 bus at the end) 
    var spi0Aqs = SpiDevice.GetDeviceSelector("SPI0"); 
    // Find all buses using the AQS query formed above 
    var devicesInfo = await DeviceInformation.FindAllAsync(spi0Aqs); 

    // Construct time settings beforehand which can't be changed 
    // once a SPI device is created 
    const Int32 DigipotChipSelectLine = 0; 
    var settings = new SpiConnectionSettings(DigipotChipSelectLine); 

    // Ask the SPI bus to open a device with the connection settings 
    // provided. Once we go out of scope, the device will be released 
    using (var spiDev = await SpiDevice.FromIdAsync(devicesInfo[0].Id, settings)) 
    { 

        // data[0] is the channel address 
        // data[1] is the resistance step (0 - 255) 
        // 0 is max digipot resistance, and 255 is no resistance 
        byte[] data = { 0x0, 0x0 }; 

        // Go over the 6 channels of the digipot 
        for (byte channel = 0; channel < 6; ++channel) 
        { 
            data[0] = channel; 

            // Step the resistance on this channel from max to min 
            for (byte r = 0; r <= 255; ++r) 
            { 
                data[1] = r; 
                spiDev.Write(data); 
                await Task.Delay(100); 
            } 

            // Step the resistance on this channel from min to max 
            for (byte r = 255; r >= 0; --r) 
            { 
                data[1] = r; 
                spiDev.Write(data); 
                await Task.Delay(100); 
            } 
        } 
    } 
} 

En el ejemplo siguiente se muestra cómo usar esta y otras API SPI para inicializar un dispositivo SPI con la configuración de conexión no predeterminada. Lo hace leyendo la intensidad de la luz de una photocell analógica conectada a un convertidor ADC108S102 A/D de 8 canales de 8 canales.

Nota:

Este ejemplo contiene varias configuraciones específicas de los dispositivos anteriores. Es posible que tenga que cambiar esta configuración para tener en cuenta su dispositivo específico. Por ejemplo, los dispositivos Raspberry Pi admiten una longitud máxima de 8/9 bits para SPI.

// Knowing that an SPI bus with 'spiBusId' exist, and has the ADC connected 
// on 'chipSelectLine', read a digital sample from some sensor wired to 'channel' 
async Task<int> AnalogRead_ADC108S102(string spiBusId, Int32 chipSelectLine, byte channel) 
{ 
    var settings = new SpiConnectionSettings(chipSelectLine); 

    // The defaults (4MHz, 8-bit, Mode0) will not work here according 
    // to the datasheet. 
    // e.g The datasheet specifies a clock freq range (8MHz - 16MHz) 
    settings.ClockFrequency = 8000000; 
    // CPOL=1, CPHA=1 
    settings.Mode = SpiMode.Mode3; 
    // Conversion happens on a 16-bit frame 
    settings.DataBitLength = 16; 
    // The ADC108S102 has 8 input analog channels, where each can be 
    // connected to a specific analog sensor and each sensor is 
    // used by a different application independently 
    // The IO requests to the SPI bus are implicitly synchronized 
    // by the driver model, plus that the ADC configuration is per 
    // 1 sampling read 
    settings.SharingMode = SpiSharingMode.Shared; 

    // Ask the SPI bus to open a shared device with the connection settings 
    // provided. 
    using (var spiDev = await SpiDevice.FromIdAsync(spiBusId, settings)) 
    { 
        if (spiDev == null) 
            return -1; 

        // Set up control register to get a conversion on a specific 
        // channel address 
        byte[] write16bitData = { (byte)(channel << 3), 0 }; 
        byte[] read16bitData = new byte[2]; 
        // The transfer is guaranteed to be atomic according to SpbCx model 
        spiDev.TransferFullDuplex(write16bitData, read16bitData); 

        ushort result = BitConverter.ToUInt16(read16bitData, 0); 
        // Get rid of the 2 LSB zeros and mask the 10-bit sampled value 
        return (int)((result >> 2) & 0x3ff); 
    } 
} 

Constructores

SpiConnectionSettings(Int32)

Inicializa una nueva instancia de SpiConnectionSettings.

Propiedades

ChipSelectLine	Obtiene o establece la línea de selección de chip para la conexión al dispositivo SPI.
ClockFrequency	Obtiene o establece la frecuencia del reloj de la conexión.
DataBitLength	Obtiene o establece la longitud de bits de los datos de esta conexión.
Mode	Obtiene o establece el SpiMode para esta conexión.
SharingMode	Obtiene o establece el modo de uso compartido de la conexión SPI.