/// <inheritdoc/>
public override void Initialize()
{
this.LogStartInitialization();
this.Device = this.Controller.GetI2CConnection(this.DeviceId);
var resetCommand = new byte[] { CCS811SWRESET, 0x11, 0xE5, 0x72, 0x8A };
this.Device.Write(resetCommand);
Thread.Sleep(100);
byte hwId = (byte)ByteOperations.GetUChar(this.ReadRawByte(CCS811HWID));
if (hwId != CCS811ID)
{
throw new System.Exception(string.Format("Incorrect ID, expected {0}, got {1}", CCS811HWID, hwId));
}
// check internal status
this.CheckError("Init");
// app valid
var status = this.ReadRawByte(CCS811STATUS);
this.LogMessage(string.Format("Status afer INIT OK? {0}", status == 16));
if ((status & 1) << 4 != 0)
{
this.CheckError("App not valid");
}
this.Device.WriteByte(CCS811APPSTART);
Thread.Sleep(100);
this.CheckError("Start");
this.WriteByte(CCS811MEASMODE, CCS811MEAS1S);
this.CheckError("MEAS");
Thread.Sleep(1500);
var bytes = this.ReadRawBytes(CCS811BASELINE, 2);
this.LogMessage(string.Format("Baseline: {0}", (bytes[0] << 8) | bytes[1]));
// data availabe?
this.LogMessage(string.Format("Data available: {0}", !((this.ReadRawByte(CCS811STATUS) & 1) << 3 == 0)));
this.CheckError("READ");
this.LogMessage("Warm up");
for (int i = 0; i < this.warmupCount; i++)
{
var data = this.ReadRawBytes(CCS811ALGRESULTDATA, 4);
this.LogMessage($"RawBytes: {ByteOperations.PrintByteArray(data)}");
Thread.Sleep(5000);
}
this.CheckError("WARMUP");
this.LogMessage("CCS811 Ready");
this.LogStartSuccess();
}
/// <inheritdoc/>
public override ISensorSample TakeReading(WeatherObservation observation)
{
this.LogTakeReadingStart();
var sensorResult = new SensorSample(this.SensorName);
var data = this.ReadRawBytes(CCS811ALGRESULTDATA, 4);
sensorResult.AddDiagnostic(ByteOperations.PrintByteArray(data));
var co2 = (data[0] << 8) | data[1];
var tvoc = (data[2] << 8) | data[3];
sensorResult.AddFinalObservation(co2, "CO2", ObservationUnits.PartsPerMillion);
sensorResult.AddFinalObservation(tvoc, "TVOC", ObservationUnits.PartsPerBillion);
observation.CO2 = co2;
observation.TVOC = tvoc;
this.LogTakeReadingComplete();
return(sensorResult);
}
/// <inheritdoc/>
public override ISensorSample TakeReading(WeatherObservation observation)
{
this.LogTakeReadingStart();
var sensorResult = new SensorSample(this.SensorName);
// Initialize for reading
this.Device.Write(new byte[] { REGCONTROLHUM, OVERSAMPLEHUM });
var control = GetControlCode();
this.Device.Write(new byte[] { REGCONTROL, (byte)control });
// Read calibaration data
var cal1 = this.ReadBytes(0x88, 24);
var cal2 = this.ReadBytes(0xA1, 1);
var cal3 = this.ReadBytes(0xE1, 7);
sensorResult.AddDiagnostic("Calibration data (1/2/3)");
sensorResult.AddDiagnostic(ByteOperations.PrintByteArray(cal1));
sensorResult.AddDiagnostic(ByteOperations.PrintByteArray(cal2));
sensorResult.AddDiagnostic(ByteOperations.PrintByteArray(cal3));
var calibrationData = ExtractcalibrationData(cal1, cal2, cal3);
// Pause per spec
var wait_time = GetWaitTime();
Thread.Sleep((int)wait_time / 1000);
// Read raw data
var data = this.ReadBytes(REGDATA, 8);
sensorResult.AddDiagnostic("Raw data");
sensorResult.AddDiagnostic(ByteOperations.PrintByteArray(data));
var rawTemp = (data[3] << 12) | (data[4] << 4) | (data[5] >> 4);
double rawTemperature = CalculateTemperature(sensorResult, calibrationData, rawTemp, out double tFine);
// Refine pressure and adjust for temperature
var rawPressure = (data[0] << 12) | (data[1] << 4) | (data[2] >> 4);
double pressureValue = CalculatePressure(sensorResult, calibrationData, rawPressure, tFine);
// Refine humidity
var rawHumidity = (data[6] << 8) | data[7];
double humidityValue = CalculateHumidity(sensorResult, calibrationData, rawHumidity, tFine);
sensorResult.AddFinalObservation(rawTemperature + this.calibrationOffset, "TEMPERATURE", ObservationUnits.DegreesCelcius);
sensorResult.AddFinalObservation(pressureValue, "PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(humidityValue, "HUMIDITY", ObservationUnits.Percentage);
var pressure = new Pressure(pressureValue, UnitsNet.Units.PressureUnit.Hectopascal);
var humidity = new RelativeHumidity(humidityValue, UnitsNet.Units.RelativeHumidityUnit.Percent);
var temperature = new Temperature(rawTemperature, UnitsNet.Units.TemperatureUnit.DegreeCelsius);
var actualAltitude = new Length(this.altitudeInMeters, UnitsNet.Units.LengthUnit.Meter);
var altitudeCalculated = WeatherHelper.CalculateAltitude(pressure);
double absHumidity = WeatherHelper.CalculateAbsoluteHumidity(temperature, humidity).GramsPerCubicMeter;
double dewPoint = WeatherHelper.CalculateDewPoint(temperature, humidity).DegreesCelsius;
double heatIndex = WeatherHelper.CalculateHeatIndex(temperature, humidity).DegreesCelsius;
double vapourPressure = WeatherHelper.CalculateActualVaporPressure(temperature, humidity).Hectopascals;
double barometricPressure = WeatherHelper.CalculateBarometricPressure(pressure, temperature, actualAltitude, humidity).Hectopascals;
double vapourPressureOverIce = WeatherHelper.CalculateSaturatedVaporPressureOverIce(temperature).Hectopascals;
double vapourPressureOverWater = WeatherHelper.CalculateSaturatedVaporPressureOverWater(temperature).Hectopascals;
double seaLevelPressure = WeatherHelper.CalculateSeaLevelPressure(pressure, actualAltitude, temperature).Hectopascals;
sensorResult.AddFinalObservation(temperature.DegreesCelsius + this.calibrationOffset, "TEMPERATURE", ObservationUnits.DegreesCelcius);
sensorResult.AddFinalObservation(pressure.Hectopascals, "PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(barometricPressure, "BAROMETRIC PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(seaLevelPressure, "SEA LEVEL PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(vapourPressureOverIce, "OVER ICE PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(vapourPressureOverWater, "OVER WATER PRESSURE", ObservationUnits.HectoPascal);
sensorResult.AddFinalObservation(humidity.Percent, "RELATIVE HUMIDITY", ObservationUnits.Percentage);
sensorResult.AddFinalObservation(absHumidity, "ABSOLUTE HUMIDITY", ObservationUnits.GramsPerCubicMeter);
sensorResult.AddFinalObservation(vapourPressure, "VAPOUR PRESSURE", ObservationUnits.Percentage);
sensorResult.AddFinalObservation(altitudeCalculated.Meters, "CALCULATED ALTITUDE", ObservationUnits.Meters);
sensorResult.AddFinalObservation(actualAltitude.Meters, "ACTUAL ALTITUDE", ObservationUnits.Meters);
sensorResult.AddFinalObservation(heatIndex, "HEAT INDEX", ObservationUnits.DegreesCelcius);
sensorResult.AddFinalObservation(dewPoint, "DEW POINT", ObservationUnits.DegreesCelcius);
observation.Temperature1 = temperature.DegreesCelsius + this.calibrationOffset;
observation.Pressure = pressure.Hectopascals;
observation.BarometricPressure = barometricPressure;
observation.SealevelPressure = seaLevelPressure;
observation.OverIcePressure = vapourPressureOverIce;
observation.OverWaterPressure = vapourPressureOverWater;
observation.RelativeHumidity = humidity.Percent;
observation.AbsoluteHumidity = absHumidity;
observation.ActualAltitude = actualAltitude.Meters;
observation.CalculatedAltitude = altitudeCalculated.Meters;
observation.HeatIndex = heatIndex;
observation.DewPoint = dewPoint;
this.LogTakeReadingComplete();
return(sensorResult);
}