private void UpdateGps()
{
int timeoutCounter = 0;
_terminate.Reset();
//Infinite loop!
while (true)
{
try
{
int eventIdx = WaitHandle.WaitAny(_waitHandles, 100, false);
if (eventIdx == WaitHandle.WaitTimeout)
{
if (_port != null && _port.IsOpen)
{
string sentence = string.Empty;
try
{
//Console.WriteLine(_port.ReadExisting());
sentence = _port.ReadLine();
timeoutCounter = 0;
HasTalked = true;
TimedOut = false;
}
//TODO: Find out why ArgumentOutOfRangeException gets thrown and catch if necessary
catch (ArithmeticException)
{
// TODO: wtf??
}
catch (TimeoutException)
{
//TODO: make GPS keep listening and just notify that no GPS is found, check cables and make sure the GPS is powered on
// Give up after the maximum timeout is reached
// The read timeout is 500ms, so the number of timeouts to seconds is a ratio of 2 timeouts for 1 second
if (!HasTalked && MaxTimeout <= timeoutCounter)
{
InvokeGpsTimeout();
//Reset the timeout count
//Stop();
break;
}
timeoutCounter++;
}
catch (IOException)
{
ClosePort();
break;
}
//Process sentence
NmeaParser.SentenceType type = _nmea.Parse(sentence);
switch (type)
{
case NmeaParser.SentenceType.Gprmc:
MyGpsData.Latitude = _nmea.Latitude;
MyGpsData.Longitude = _nmea.Longitude;
MyGpsData.Speed = _nmea.Speed;
MyGpsData.SatelliteTime = _nmea.SatelliteTime;
MyGpsData.Course = _nmea.Course;
MyGpsData.MagVar = _nmea.MagVar;
HasFix = _nmea.HasFix;
Time = _nmea.Timestamp;
InvokeGpsLocationUpdated();
break;
case NmeaParser.SentenceType.Gpgsv:
Satellites = _nmea.Satellites;
SatellitesVisible = _nmea.SatelliteCount;
InvokeGpsStatUpdated();
break;
case NmeaParser.SentenceType.Gpgsa:
MyGpsData.Pdop = _nmea.Pdop;
MyGpsData.Hdop = _nmea.Hdop;
MyGpsData.Vdop = _nmea.Vdop;
MyGpsData.SatellitesUsed = _nmea.SatellitesUsed;
InvokeGpsStatUpdated();
break;
case NmeaParser.SentenceType.Gpgga:
MyGpsData.Latitude = _nmea.Latitude;
MyGpsData.Longitude = _nmea.Longitude;
MyGpsData.Altitude = _nmea.Altitude;
Time = _nmea.Timestamp;
InvokeGpsLocationUpdated();
break;
case NmeaParser.SentenceType.Gpvtg:
MyGpsData.Speed = _nmea.Speed;
break;
default:
//gpsConnected = false;
break;
}
}
else
{
// The port was previously closed due to being out of sync, reopen
Thread.Sleep(500);
ClosePort();
OpenPort();
}
InvokeGpsUpdated();
}
else //Terminate was signaled
{
break;
}
}
catch (ObjectDisposedException)
{
break;
}
}
}
