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Use .NET IoT Libraries on Windows, Linux, and macOS computers

The .NET IoT libraries are commonly used to develop code for Raspberry Pi and other IoT devices. However, you can also use them to develop code for Windows, Linux, and macOS PCs using a USB-to-serial adapter such as the FTDI FT232H. This article shows you how to use the .NET IoT libraries to communicate with devices connected to the FT232H adapter.

Tip

This article uses an FTDI FT232H adapter, but you can use any USB-to-serial adapter that is supported by the .NET IoT libraries, such as the FT2232H, FT4232H, and FT4222. Check the list of supported device bindings for more information.

Prerequisites

Ensure you have installed the D2XX drivers for your USB-to-serial adapter, which are found on the FTDI website.

Note

Windows devices may automatically install the drivers when you plug in the adapter. Check Device Manager for a device named USB Serial Converter listed under Universal Serial Bus controllers. The device's driver provider should be FTDI.

List available devices

Before you can create a GPIO, I2C, or SPI device, you must identify the connected USB-to-serial adapter. The following code lists the connected FTDI devices:

using Iot.Device.FtCommon;

var devices = FtCommon.GetDevices();
Console.WriteLine($"{devices.Count} available device(s)");
foreach (var device in devices)
{
    Console.WriteLine($"  {device.Description}");
    Console.WriteLine($"    Flags: {device.Flags}");
    Console.WriteLine($"    Id: {device.Id}");
    Console.WriteLine($"    LocId: {device.LocId}");
    Console.WriteLine($"    Serial number: {device.SerialNumber}");
    Console.WriteLine($"    Type: {device.Type}");
}

if (devices.Count == 0)
{
    Console.WriteLine("No device connected");
    return;
}

In the preceding code, the FtCommon.GetDevices() method returns a list of all connected FTDI devices.

Use a GPIO device

Here's a hardware implementation of the Blink an LED tutorial that uses the FTDI FT232H adapter to control an LED:

A picture of a breadboard with an FT232H adapter, a resister, an LED, and connecting wires.

In the preceding image, the LED circuit is very similar to the original tutorial. The only difference is that the LED is connected to pin D7 on the FT232H adapter instead of pin 18 on the Raspberry Pi.

The code for the tutorial is also similar to the original tutorial:

using System.Device.Gpio;
using Iot.Device.Ft232H;
using Iot.Device.FtCommon;

Console.WriteLine("Blinking LED. Press Ctrl+C to end.");

Ft232HDevice ft232h = new Ft232HDevice(FtCommon.GetDevices()[0]);
GpioController controller = ft232h.CreateGpioController();

int pin = Ft232HDevice.GetPinNumberFromString("D7");
controller.OpenPin(pin, PinMode.Output);
bool ledOn = true;
while (true)
{
    controller.Write(pin, ledOn ? PinValue.High : PinValue.Low);
    Thread.Sleep(1000);
    ledOn = !ledOn;
}

In the preceding code:

  • An instance Ft232HDevice is created by passing the first device ID returned by FtCommon.GetDevices() to the constructor.
  • An instance of GpioController named controller is created by calling CreateGpioController() on the Ft232HDevice instance. This GpioController instance performs the same functions as the GpioController instance in the original tutorial.
  • The integer value of the pin is retrieved by calling GetPinNumberFromString() on the Ft232HDevice instance and passing in the alphanumeric pin name D7.
  • The rest of the code is identical to the original tutorial.

Use an I2C device

For I2C communication, the D0 and D1 pins on the FT232H adapter are used for the SDL and SCA lines, respectively. The I2C selector switch on the FT232H adapter must be set to On.

Here's a hardware implementation of the Read environmental conditions from a sensor tutorial that uses the FTDI FT232H adapter to read temperature, humidity, and barometric pressure from a BME280 sensor:

A picture of a breadboard with an FT232H adapter, a BME280 breakout board, and connecting wires.

In the preceding image:

  • The D0 and D1 pins on the FT232H adapter are connected to the SDL and SCA pins on the BME280 breakout board, respectively.
  • The I2C selector switch on the BME280 breakout board is set to On.
using System.Device.I2c;
using Iot.Device.Bmxx80;
using Iot.Device.Bmxx80.PowerMode;
using Iot.Device.Ft232H;
using Iot.Device.FtCommon;

Ft232HDevice ft232h = new Ft232HDevice(FtCommon.GetDevices()[0]);
I2cConnectionSettings i2cSettings = new I2cConnectionSettings(0, Bme280.SecondaryI2cAddress);

using I2cDevice i2cDevice = ft232h.CreateI2cDevice(i2cSettings);
using Bme280 bme280 = new Bme280(i2cDevice);

int measurementTime = bme280.GetMeasurementDuration();

while (true)
{
    Console.Clear();

    bme280.SetPowerMode(Bmx280PowerMode.Forced);
    Thread.Sleep(measurementTime);

    bme280.TryReadTemperature(out var tempValue);
    bme280.TryReadPressure(out var preValue);
    bme280.TryReadHumidity(out var humValue);
    bme280.TryReadAltitude(out var altValue);

    Console.WriteLine($"Temperature: {tempValue.DegreesCelsius:0.#}\u00B0C");
    Console.WriteLine($"Pressure: {preValue.Hectopascals:#.##} hPa");
    Console.WriteLine($"Relative humidity: {humValue.Percent:#.##}%");
    Console.WriteLine($"Estimated altitude: {altValue.Meters:#} m");

    Thread.Sleep(1000);
}

In the preceding code:

  • An instance Ft232HDevice is created by passing the first device ID returned by FtCommon.GetDevices() to the constructor.
  • An instance of I2cDevice is created by calling CreateI2cDevice() on the Ft232HDevice instance. This I2cDevice instance performs the same functions as the I2cDevice instance in the original tutorial.
  • The rest of the code is identical to the original tutorial.

Use an SPI device

For SPI communication, the D0, D1, D2, and D3 pins on the FT232H adapter are used for the SCK, MOSI, MISO, and CS lines, respectively. The I2C selector switch on the FT232H adapter must be set to Off.

A picture of the back of the FT232H breakout depicting the SPI pins.

Here's a hardware implementation of the Read values from an analog-to-digital converter tutorial that uses the FTDI FT232H adapter to read values from an MCP3008 ADC:

A picture of a breadboard with an FT232H adapter, an MCP3008 chip, and connecting wires.

In the preceding image:

  • The D0, D1, D2, and D3 pins on the FT232H adapter are connected to the CLK, DIN, DOUT,and CS/SHDN pins on the MCP3008, respectively.
  • The I2C selector switch on the MCP3008 breakout board is set to Off.
using System.Device.Gpio;
using System.Device.Spi;
using Iot.Device.Adc;
using Iot.Device.Ft232H;
using Iot.Device.FtCommon;

var devices = FtCommon.GetDevices();
var ft232h = new Ft232HDevice(devices[0]);
var hardwareSpiSettings = new SpiConnectionSettings(0, 3) { ClockFrequency = 1_000_000, DataBitLength = 8, ChipSelectLineActiveState = PinValue.Low };
using SpiDevice spi = ft232h.CreateSpiDevice(hardwareSpiSettings);
using var mcp = new Mcp3008(spi);
while (true)
{
    Console.Clear();
    double value = mcp.Read(0);
    Console.WriteLine($"{value}");
    Console.WriteLine($"{Math.Round(value/10.23, 1)}%");
    Thread.Sleep(500);
}

In the preceding code:

  • An instance Ft232HDevice is created by passing the first device ID returned by FtCommon.GetDevices() to the constructor.
  • An instance of SpiDevice is created by calling CreateSpiDevice() on the Ft232HDevice instance. This SpiDevice instance performs the same functions as the SpiDevice instance in the original tutorial.
  • The rest of the code is identical to the original tutorial.

Get the code

The code for this tutorial is available on GitHub.