protected void ProcessGPSTimeout()
{
mStatus = GPS_STATUS.OFFLINE;
mGPSPosition.Invalidate();
OnRaiseGPSStatusChangedEvent(new GPSStatusEvent(mStatus));
}
private void ProcessNewSentence(string sentence)
{
if (sentence.Length < 6)
{
OnRaiseGPSStatusChangedEvent(new GPSStatusEvent(GPS_STATUS.OFFLINE));
CNXLog.ErrorFormat("NMEAClient short sentence {0}", sentence);
return;
}
try
{
//CNXLog.InfoFormat("NMEAClient ProcessNewSentence {0}", sentence);
bool updateAvailable = false;
string sentenceType = "";
if (sentence.Contains("RMC"))
{
sentenceType = "RMC";
}
else if (sentence.Contains("GGA"))
{
sentenceType = "GGA";
}
else if (sentence.Contains("GSA"))
{
sentenceType = "GSA";
}
// Determine the type of sentence.
// The NMEA specification states that the first two letters of a sentence may change.
// For example, for "$GPGSV" there may be variations such as "$__GSV" where the first two letters change.
// As a result, we need only test the last three characters.
// Is this a GPRMC sentence?
if (sentenceType.Equals("RMC", StringComparison.Ordinal))
{
updateAvailable = mGPSPosition.ParseRMC(sentence);
if (!updateAvailable)
{
OnRaiseGPSPositionChangedEvent(new GPSPositionEvent(mGPSPosition));
}
}
else if (sentenceType.Equals("GGA", StringComparison.Ordinal))
{
// dont update on GGA, only augment error estimates.
updateAvailable = mGPSPosition.ParseGGA(sentence);
}
else if (sentenceType.Equals("GSA", StringComparison.Ordinal))
{
updateAvailable = mGPSPosition.ParseGSA(sentence);
}
if (updateAvailable)
{
mLastNMEASentenceType = sentenceType;
// report any status changes
GPS_STATUS status = GPS_STATUS.OFFLINE;
switch (mGPSPosition.NMEAMode)
{
case GPSPosition.NMEAMODE.NO_FIX:
status = GPS_STATUS.Connected;
mTravellingState = MovingState.Unknown;
break;
case GPSPosition.NMEAMODE.NO_MODE:
status = GPS_STATUS.Connected | GPS_STATUS.GPSResponding;
mTravellingState = MovingState.Unknown;
break;
case GPSPosition.NMEAMODE.TWO_DIMENSION:
case GPSPosition.NMEAMODE.THREE_DIMENSION:
status = GPS_STATUS.Connected | GPS_STATUS.GPSResponding | GPS_STATUS.Fix;
// set the travelling state
mAverageVelocity.Value = mGPSPosition.SpeedOverGround;
//lat = mG
mTravellingState = (mAverageVelocity.Value > mMovingThreshold) ? MovingState.Moving : MovingState.Stationary;
break;
}
if (status != mStatus)
{
mStatus = status;
OnRaiseGPSStatusChangedEvent(new GPSStatusEvent(mStatus));
//Console.WriteLine("Fired Status Changed.");
}
// only update from RMC sentences as other sentences dont have date & time.
if (sentenceType.Equals("RMC", StringComparison.Ordinal))
{
//Console.WriteLine("Firing Position Changed.");
//CNXLog.InfoFormat("GPS State {0}, {1}", mStatus, mGPSPosition.CurrentPosition.ToString());
//if (mGPSPosition.Tag.EndsWith("RMC", StringComparison.Ordinal))
if ((mStatus & GPS_STATUS.Fix) == GPS_STATUS.Fix)
{
//CNXLog.InfoFormat(mGPSPosition.CurrentPosition.ToString());
OnRaiseGPSPositionChangedEvent(new GPSPositionEvent(mGPSPosition));
//CNXLog.InfoFormat("OnRaiseGPSPositionChangedEvent completed.");
//CNXLog.InfoFormat(mGPSPosition.CurrentPosition.ToString());
//Console.WriteLine("Fired Position Changed.");
}
}
}
//CNXLog.InfoFormat("GPS State {0}, {1}", mStatus, mGPSPosition.CurrentPosition.ToString());
}
catch (Exception e)
{
CNXLog.Error(String.Format("NMEAClient ProcessNewSentence {0}", sentence), e);
}
}
public GPSStatusEvent(GPS_STATUS status)
{
Status = status;
}
