//=======================================================================
#region -= static methods =-
//=======================================================================
public static GsvData Parse(string inputString)
{
//---- declare vars
GsvData data = new GsvData();
string dataString = inputString.Substring(0, inputString.IndexOf('*')); // strip off the checksum
string[] values = dataString.Split(',');
//---- if we don't have 20 (header + 19), it's no good
if (values.Length < 20)
{
throw new FormatException();
}
//---- number of messages
data.MessageCount = int.Parse(values[1]);
//---- message number
data.MessageNumber = int.Parse(values[2]);
//---- total number of satellites in view
data.SatellitesInView = int.Parse(values[3]);
//---- loop through the satellites (up to 4)
for (int i = 0; i < 4; i++)
{
//---- create a new satellite
Satellite sat = new Satellite();
//---- satellite information starts at index 4, goes for 4 lines, and then starts over (4-7), (8-11), (12-15), (16-19)
int satIndex = (4 + (4 * i));
//---- satellite ID
sat.ID = (string.IsNullOrEmpty(values[satIndex]) ? 0 : int.Parse(values[satIndex]));
//---- if we got a satellite
if (sat.ID > 0)
{
//---- elevation
sat.AngleOfElvation = (string.IsNullOrEmpty(values[satIndex + 1]) ? 0 : int.Parse(values[satIndex + 1]));
//---- azimuth
sat.Azimuth = (string.IsNullOrEmpty(values[satIndex + 2]) ? 0 : int.Parse(values[satIndex + 2]));
//---- signal strength
sat.SignalStrength = (string.IsNullOrEmpty(values[satIndex + 3]) ? 0 : int.Parse(values[satIndex + 3]));
//---- used in fix? [TODO: Verify this assumption of signal 00 is all right]
if (sat.SignalStrength > 0)
{
sat.UsedInPositionFix = true;
}
else
{
sat.UsedInPositionFix = false;
}
//---- add the sat
data.Satellites.Add(sat);
}
}
//---- return
return(data);
//$GPGSV,1,1,13,02,02,213,,03,-3,000,,11,00,121,,14,13,172,05*67
//1 = Total number of messages of this type in this cycle
//2 = Message number
//3 = Total number of SVs in view
//4 = SV PRN number
//5 = Elevation in degrees, 90 maximum
//6 = Azimuth, degrees from true north, 000 to 359
//7 = SNR, 00-99 dB (null when not tracking)
//8-11 = Information about second SV, same as field 4-7
//12-15= Information about third SV, same as field 4-7
//16-19= Information about fourth SV, same as field 4-7
}
//=======================================================================
#region -= static methods =-
//=======================================================================
public static GsaData Parse(string inputString)
{
//---- declare vars
GsaData data = new GsaData();
string dataString = inputString.Substring(0, inputString.IndexOf('*')); // strip off the checksum
string[] values = dataString.Split(',');
//---- if we don't have 18 (header + 17), it's no good
if (values.Length < 18)
{
throw new FormatException();
}
//---- mode
data.FixMode = FixModeUtil.Parse(values[1]);
//---- fix type
data.FixType = (FixType)int.Parse(values[2]);
//---- loop through the satellites (3-14)
for (int i = 3; i < 15; i++)
{
if (!string.IsNullOrEmpty(values[i]))
{
//---- create a new satellite
Satellite sat = new Satellite();
//---- these we don't know, so set to -1/false
sat.AngleOfElvation = -1;
sat.Azimuth = -1;
sat.SignalStrength = -1;
sat.UsedInPositionFix = false;
//---- get the satellite ID
sat.ID = int.Parse(values[i]);
//---- add the sat to the collection
data.SatellitesUsed.Add(sat);
}
}
//---- PDOP
data.DilutionOfPrecision = decimal.Parse(values[15]);
//---- HDOP
data.HorizontalDilutionOfPrecision = decimal.Parse(values[16]);
//---- VDOP
data.VerticalDilutionOfPrecision = decimal.Parse(values[17]);
//---- return
return(data);
//GPS DOP and active satellites
//eg1. $GPGSA,A,3,,,,,,16,18,,22,24,,,3.6,2.1,2.2*3C
//eg2. $GPGSA,A,3,19,28,14,18,27,22,31,39,,,,,1.7,1.0,1.3*35
//1 = Mode:
// M=Manual, forced to operate in 2D or 3D
// A=Automatic, 3D/2D
//2 = Mode:
// 1=Fix not available
// 2=2D
// 3=3D
//3-14 = IDs of SVs used in position fix (null for unused fields)
//15 = PDOP
//16 = HDOP
//17 = VDOP
}