public void LogData(HeartRateServiceData data)
{
String line = "";
if (!File.Exists(filename))
{
line += HeartRateServiceData.GetCsVHeader() + Environment.NewLine;
}
line += data.ToString();
using (var streamWriter = new StreamWriter(filename, true))
{
streamWriter.WriteLine(line);
}
}
private void HeartRate_ValueChanged(
GattCharacteristic sender,
GattValueChangedEventArgs args)
{
var value = args.CharacteristicValue;
if (value.Length == 0)
{
return;
}
using (var reader = DataReader.FromBuffer(value))
{
byte[] data = new byte[value.Length];
reader.ReadBytes(data);
var bpm = -1;
var flags = data[0];
var isshort = (flags & 1) == 1; // 1 == UINT16
var contactSensor = (ContactSensorStatus)((flags >> 1) & 3);
var minLength = isshort ? 3 : 2;
if (value.Length < minLength)
{
Debug.WriteLine($"Buffer was too small. Got {value.Length}, expected {minLength}.");
return;
}
HeartRateServiceData hrsd = new HeartRateServiceData(data);
LogData(hrsd);
bpm = hrsd.HeartRateMeasurement;
Debug.WriteLine($"Read {flags.ToString("X")} {contactSensor} {bpm}");
foreach (var rr in hrsd.RRIntervals)
{
Debug.WriteLine($"RR Interval {rr}");
}
HeartRateUpdated?.Invoke(contactSensor, bpm);
}
}