/// <summary>
/// Raises the position changed event
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
protected virtual void OnPositionChanged(object sender, PozyxPositionEventArgs args)
{
PositionChanged?.Invoke(sender, args);
}
/// <summary>
/// Update position
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
private void OnPositionChanged(object sender, PozyxPositionEventArgs args)
{
Position = args;
PositionChanged?.Invoke(this, args);
}
/// <summary>
/// Open reader
/// </summary>
/// <returns></returns>
private async Task Reader(SerialDevice port, CancellationToken cancel)
{
// create reader
var reader = new DataReader(port.InputStream);
reader.UnicodeEncoding = Windows.Storage.Streams.UnicodeEncoding.Utf8;
reader.InputStreamOptions = InputStreamOptions.Partial;
// create buffer
var buffer = new StringBuilder();
// keep reading
while (!cancel.IsCancellationRequested)
{
try
{
// create read task
var read = await reader.LoadAsync(20).AsTask(cancel);
// get bytes
var bytes = new byte[read];
reader.ReadBytes(bytes);
// get text
var text = Encoding.ASCII.GetString(bytes);
// var text = reader.ReadString(read);
buffer.Append(text);
// find latest position
PozyxPositionEventArgs position = null;
// keep reading results
while (buffer.Length > 0)
{
// keep processing
int i = 0;
for (; i < buffer.Length; i++)
{
if (buffer[i] == 10)
{
continue;
}
if (buffer[i] == 13)
{
break;
}
}
// done processing
if (i == buffer.Length)
{
break;
}
// remove from buffer
var line = buffer.ToString(0, i).Trim('\n', '\r');
buffer.Remove(0, i + 1);
// write line
Debug.WriteLine(line);
// POS,0x0,11005,12137,1767
var items = line.Split(',');
if (items.Length != 5)
{
break;
}
if (items[0] != "POS")
{
break;
}
// parse X, Y, Z
int x, y, z;
if (!int.TryParse(items[2], out x))
{
break;
}
if (!int.TryParse(items[3], out y))
{
break;
}
if (!int.TryParse(items[4], out z))
{
break;
}
// set new position
position = new PozyxPositionEventArgs(x, y, z);
}
// process if position received
if (position != null)
{
// store new position
Position = position;
// signal position changed
OnPositionChanged(this, position);
}
}
catch (Exception ex)
{
Debug.WriteLine(ex);
break;
}
}
}