private async void _periodicTimer_Tick(object sender, object e)
{
Bmp180SensorData sensorData = null;
// Read and format Sensor data
try
{
sensorData = await _bmp180.GetSensorDataAsync(Bmp180AccuracyMode.UltraHighResolution);
Temperature = sensorData.Temperature;
Pressure = sensorData.Pressure;
Altitude = sensorData.Altitude;
LastUpdated = DateTime.UtcNow.ToString();
}
catch (Exception)
{
LastUpdated = "Sensor Error! Can't get values from sensor.";
}
if (sensorData != null)
{
// reference: https://docs.microsoft.com/en-us/azure/iot-hub/iot-hub-csharp-csharp-getstarted#create-a-simulated-device-app
// send to IoT Hub
SendDeviceToCloudMessagesAsync(sensorData);
}
}
public async Task <Bmp180SensorData> GetSensorDataAsync(Bmp180AccuracyMode oss)
{
// Create the return object.
var sensorData = new Bmp180SensorData();
// Read the Uncompestated values from the sensor.
var tData = await ReadUncompenstatedTemperature();
var pData = await ReadUncompenstatedPressure(oss);
// Keep raw data for debug
sensorData.UncompenstatedTemperature = tData;
sensorData.UncompenstatedPressure = pData;
var ut = (tData[0] << 8) + tData[1];
var up = (pData[0] * 256.0) + pData[1] + (pData[2] / 256.0);
// Calculate real values
var b5 = calculateB5(ut);
var t = (b5 + 8) >> 4;
sensorData.Temperature = t / 10.0;
var s = sensorData.Temperature - 25.0;
var x = (x2 * Math.Pow(s, 2)) + (x1 * s) + x0;
var y = (y2 * Math.Pow(s, 2)) + (y1 * s) + y0;
var z = (up - x) / y;
sensorData.Pressure = (p2 * Math.Pow(z, 2)) + (p1 * z) + p0;
sensorData.Altitude = 44330 * (1 - Math.Pow(sensorData.Pressure / 1013.25, 1 / 5.255));
return(sensorData);
}
private async void SendDeviceToCloudMessagesAsync(Bmp180SensorData sensorData)
{
var messageString = JsonConvert.SerializeObject(new WeatherDTO
{
// bestAccuracyLocationName
dateTime = LastUpdated,
temperature = sensorData.Temperature,
pressure = sensorData.Pressure,
altitude = sensorData.Altitude,
latitude = LocationManager.currentlocation.Position.Latitude,
longitude = LocationManager.currentlocation.Position.Longitude,
});
var message = new Microsoft.Azure.Devices.Client.Message(Encoding.ASCII.GetBytes(messageString));
await deviceClient.SendEventAsync(message);
}
