/// <summary>
/// Parses data received from heart rate sensors.
/// </summary>
/// <param name="bytes">String received from heart rate sensor.</param>
/// <returns>Returns parsed data from the device.</returns>
public HeartBeatSensorData Parse(byte[] bytes)
{
HeartBeatSensorData sensorData = new HeartBeatSensorData();
int offset;
HeaderData header = GetHeader(bytes, out offset);
if (header.IsValid)
{
sensorData.Firmware = header.Firmware;
sensorData.Hardware = header.Hardware;
PayloadData payload = GetData(bytes, ref offset);
sensorData.IsAvailable = true;
sensorData.Battery = payload.Battery;
sensorData.HeartBeatPerMinute = payload.HeartRate;
sensorData.TotalHeartBeats = payload.HeartBeatNumber;
sensorData.HeartBeatTimestamps = payload.HeartBeatTimestamps;
if (payload.ContainsStrideData)
{
sensorData.Speed = payload.Speed;
sensorData.Distance = payload.Distance;
sensorData.Stride = payload.Stride;
}
}
return(sensorData);
}
private void RaiseUpdateEvent(HeartBeatSensorData data, Exception error)
{
if (Updated != null)
{
Updated(this, new HeartBeatSensorUpdateEventArgs(data, error));
}
}
public async void LoadAsync()
{
// While WinRT designer can show you actual available devices it can also cause weird stuff. (like "Element not found!" exception or VS crash)
#if SILVERLIGHT
if (DesignerProperties.IsInDesignTool)
#elif NETFX_CORE
if (Windows.ApplicationModel.DesignMode.DesignModeEnabled)
#endif
{
// Show some devices in design time.
Devices.Add(new DeviceInformation {
DisplayName = "Mock device"
});
Devices.Add(new DeviceInformation {
DisplayName = "HxM device"
});
HeartBeatSensorData = new HeartBeatSensorData();
HeartBeatSensorData.Battery = 90;
HeartBeatSensorData.Distance = 23.3452;
HeartBeatSensorData.Firmware = "9500.550.V1f";
HeartBeatSensorData.Hardware = "9500.550.V1f";
HeartBeatSensorData.HeartBeatPerMinute = 67;
HeartBeatSensorData.TotalHeartBeats = 234;
HeartBeatSensorData.Stride = 123;
HeartBeatSensorData.Speed = 5.456;
HeartBeatSensorData.IsAvailable = true;
HeartBeatSensorData.IsStrideAvailabe = true;
OnPropertyChanged("HeartBeatSensorData");
return;
}
// Get devices in platform independent data structure.
// Method sensorController.ConnectToDeviceAsync will figure out what to do with it.
var devices = await devicesController.GetAllDevicesAsync();
foreach (var device in devices)
{
Devices.Add(device);
}
}
/// <summary>
/// Starts processing sensor data from device.
/// <remarks>You need to be connected to the device!</remarks>
/// <remarks>This method will complete when called <see cref="Stop" /> method.</remarks>
/// </summary>
public async Task StartAsync()
{
int interval = (int)Math.Round(1000 / (float)updateFrequency);
cancel = false;
while (!cancel)
{
try
{
reader.InputStreamOptions = InputStreamOptions.Partial;
// All messages should be size of 60 bytes however it is possible
// that device was unable to keep up all the data and receives more than 60 bytes.
// Also a different sensor can also have different message size.
uint count = await reader.LoadAsync(200);
// I had some weird issues with ReadBytes but ReadByte worked just fine.
byte[] bytes = new byte[count];
for (int i = 0; i < count; ++i)
{
bytes[i] = reader.ReadByte();
}
// Parse data and send new data to listeners.
HeartBeatSensorData data = heartRateSensorParser.Parse(bytes);
data.DeviceName = lastConnectedDeviceName;
RaiseUpdateEvent(data, null);
// Sleep until next interval
await Task.Delay(interval);
}
catch (Exception ex)
{
RaiseUpdateEvent(null, ex);
}
}
}
