Working with Raspberry Pi 3 + Windows 10 IoT Core + DHT22 - windows-10-iot-core

Question

Wondering if there is any sample wiring and code for Raspberry Pi 3 + Windows 10 IoT Core + DHT22 ? Thanks!

Answer 1

if you go to the tutorials tab it will show you some sample code and wiring for lighting an LED.
I hope this answered your question.
CodeMaster5678

Answer 2

static class DHT22
{
private const int intGpioData = 18;
private static GpioPin gpioData;
public static void Start()
{
//Init GPIO And Capture Data Every 2000ms
GpioController gpioController = GpioController.GetDefault();
gpioData = gpioController.OpenPin(intGpioData);
gpioData.SetDriveMode(GpioPinDriveMode.InputPullUp);
new Timer(new TimerCallback((obj) => { GetData(); }), null, 2000, 2000);
}
private static void GetData()
{
byte[] data = new byte[40];
gpioData.SetDriveMode(GpioPinDriveMode.Output);
gpioData.Write(GpioPinValue.Low);
Task.Delay(1).Wait();
gpioData.SetDriveMode(GpioPinDriveMode.InputPullUp);
//Record Data
while (gpioData.Read() == GpioPinValue.High) ;
while (gpioData.Read() == GpioPinValue.Low) ;
while (gpioData.Read() == GpioPinValue.High) ;
byte low;
for (int i = 0; i < 40; i++)
{
low = 0;
data[i] = 0;
while (gpioData.Read() == GpioPinValue.Low && low <= byte.MaxValue)
low++;
while (gpioData.Read() == GpioPinValue.High && data[i] <= byte.MaxValue)
data[i]++;
}
//Analyze Data
byte humiH = 0;
byte humiL = 0;
byte tempH = 0;
byte tempL = 0;
byte sum = 0;
for (short i = 7; i >= 0; i--)
{
byte bit = data[7 - i] >= 11 ? (byte)1 : (byte)0;
humiH += (byte)(bit << i);
}
for (short i = 7; i >= 0; i--)
{
byte bit = data[15 - i] >= 11 ? (byte)1 : (byte)0;
humiL += (byte)(bit << i);
}
for (short i = 7; i >= 0; i--)
{
byte bit = data[23 - i] >= 11 ? (byte)1 : (byte)0;
tempH += (byte)(bit << i);
}
for (short i = 7; i >= 0; i--)
{
byte bit = data[31 - i] >= 11 ? (byte)1 : (byte)0;
tempL += (byte)(bit << i);
}
for (short i = 7; i >= 0; i--)
{
byte bit = data[39 - i] >= 11 ? (byte)1 : (byte)0;
sum += (byte)(bit << i);
}
//Verify Data
if ((byte)(humiH + humiL + tempH + tempL) == sum)
{
double humidity = (double)(humiH * 256 + humiL) / 10;
double temperature = (double)(tempH * 256 + tempL) / 10;
Debug.WriteLine(humidity + "% " + temperature + "°C");
}
}
}

Answer 3

If you are using C++, here is an example.
https://github.com/Microsoft/Windows-iotcore-samples/tree/develop/Samples/GpioOneWire
Also, if you want to stick to C#, this does work. I used this today with 2 dht11 sensors.
This is the github link:
https://github.com/porrey/Dht
Nuget package:
https://www.nuget.org/packages/Dht/
If you are comfortable with C++, then use that. If not I recommend the Nuget package, only because I verified that it works today. The dht11 sensors seem to have a lot of variance. I have a 3 degree different on two sensors.