public AnalogTemperature(
IAnalogInputPort analogInputPort,
KnownSensorType sensorType,
Calibration calibration = null
)
{
this.AnalogInputPort = analogInputPort;
//
// If the calibration object is null use the defaults for TMP35.
//
if (calibration == null)
{
calibration = new Calibration();
}
switch (sensorType)
{
case KnownSensorType.TMP35:
case KnownSensorType.LM35:
case KnownSensorType.LM45:
_yIntercept = 0;
_millivoltsPerDegreeCentigrade = 10;
break;
case KnownSensorType.LM50:
case KnownSensorType.TMP36:
_yIntercept = 500;
_millivoltsPerDegreeCentigrade = 10;
break;
case KnownSensorType.TMP37:
_yIntercept = 0;
_millivoltsPerDegreeCentigrade = 20;
break;
case KnownSensorType.Custom:
_yIntercept = calibration.MillivoltsAtSampleReading - (calibration.SampleReading * calibration.MillivoltsAtSampleReading);
_millivoltsPerDegreeCentigrade = calibration.MillivoltsPerDegreeCentigrade;
break;
default:
throw new ArgumentException("Unknown sensor type", nameof(sensorType));
}
// wire up our observable
// have to convert from voltage to temp units for our consumers
// this is where the magic is: this allows us to extend the IObservable
// pattern through the sensor driver
AnalogInputPort.Subscribe(
new FilterableObserver <FloatChangeResult, float>(
h => {
var newTemp = VoltageToTemperature(h.New);
var oldTemp = VoltageToTemperature(h.Old);
this.Temperature = newTemp; // save state
RaiseEventsAndNotify(
new AtmosphericConditionChangeResult(
new AtmosphericConditions(newTemp, 0, 0),
new AtmosphericConditions(oldTemp, 0, 0)
));
})
);
}
