public static IRMessage EndRecording()
{
double newTime, oldTime;
List <double> intervalList = new List <double>();
GpioChangeRecord changeRecord;
statusLED.Write(GpioPinValue.Low);
irReceiverReader.Stop();
if (irReceiverReader.IsEmpty)
{
return(null);
}
changeRecord = irReceiverReader.GetNextItem();
oldTime = changeRecord.RelativeTime.TotalMilliseconds;
while (!irReceiverReader.IsEmpty)
{
changeRecord = irReceiverReader.GetNextItem();
newTime = changeRecord.RelativeTime.TotalMilliseconds;
intervalList.Add(newTime - oldTime);
oldTime = newTime;
}
if (!intervalList.Any())
{
return(null);
}
return(new IRMessage(intervalList));
}
private void Timer_Tick(object sender, object e)
{
while (!irReceiverReader.IsEmpty)
{
HandleChange(irReceiverReader.GetNextItem());
}
UpdateDebugString();
}
private async Task ReadValuesFromDhtAsync()
{
try
{
var reading = new DhtSensorReading();
CancellationTokenSource cancellationSource = new CancellationTokenSource();
cancellationSource.CancelAfter(TIMEOUT_DATA_READING);
_changeReader.Clear();
_changeReader.Start();
await SendInitialPulseAsync();
// Wait for 43 falling edges to show up
await _changeReader.WaitForItemsAsync(43).AsTask(cancellationSource.Token);
// discard first two falling edges
_changeReader.GetNextItem();
_changeReader.GetNextItem();
// pulse widths greater than 110us are considered 1's
TimeSpan oneThreshold = new TimeSpan(110 * 10000000 / 1000000);
TimeSpan current = _changeReader.GetNextItem().RelativeTime;
for (int i = 0; i < 40; i++)
{
TimeSpan next = _changeReader.GetNextItem().RelativeTime;
TimeSpan pulseWidth = next.Duration() - current.Duration();
if (pulseWidth.Duration() > oneThreshold.Duration())
{
reading.Bits[40 - i - 1] = true;
}
current = next;
}
if (reading.IsValid())
{
UpdateValuesOnUI(reading.Temperature(), reading.Humidity());
UpdateStatus("OK");
}
else
{
throw new Exception("Invalid sensor data received!");
}
}
catch (Exception ex)
{
UpdateValuesOnUI(double.NaN, double.NaN);
if (ex is TaskCanceledException)
{
UpdateStatus("Timeout while reading sensor data!");
}
else
{
UpdateStatus(ex.Message);
}
}
finally
{
_changeReader.Stop();
}
}