Differences

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--- code:emulator [2008/07/19 23:33] – external edit 127.0.0.1
+++ code:emulator [2021/03/04 14:52] (current) – [C code to simulate NMEA output from a GPS in real time - with live Google Earth Display] rocketboy
@@ Line 2: / Line 2: @@
 The code here performs the following:
-**GPSgen.c** - converts source balloon track KML files into a GPS NEMA logs (i.e. files containing $GPGGA messages etc.)
+**GPSgen.c** - converts source balloon track KML files into GPS NEMA logs (i.e. files containing $GPGGA messages etc.)
 **emulate.c** - outputs a GPS log to the PC serial port - pacing the output to simulate real time gps output - at the same time //emulate// creates a real-time KML file so you can see where the payload is currently flying using Google Earth.
 **outer.kml** is a kml shell that is configured to initiate the real-time display of the kml file generated by emulate (open //outer.kml// file from Google Earth to initiate the real-time display).
 Together these programs allow real time testing of payloads with a GPS simulation - as if the payload was flying through the coordinates in the source KML. This allows cut-down algorithms etc. to be checked.  The source KML can be from a previous balloon flight - the output of a balloon trajectory forecast - or can be hand crafted to test something specific.
+Some test NMEA files can be found [[code:NMEA|here]]
 The screenshot below shows the emulation of the Pegasus 1 flight running in the top left DOS window, the generated NMEA in the bottom left DOS window against a background of a Google Earth real-time display of the flight.
@@ Line 265: / Line 267: @@
 	while(1)
 	{
-		i = fscanf(stdin,"%128s",buf); // read a non whitespace from the input
+		i = scanf("%128s",buf); // read a non whitespace from the input
 		if (i != 1)
 		{
@@ Line 299: / Line 301: @@
 	// get first LineString co-ordinate as launch position
-	i = fscanf(stdin,"%f , %f , %f",&FromLon,&FromLat,&FromAlt);
+	i = scanf("%f , %f , %f",&FromLon,&FromLat,&FromAlt);
 	if (i !=3)
 	{
 		fprintf(stderr,"1st coordinate not 3D\n");
-		return(1); // abnormal termination
+		return 1; // abnormal termination
 	}
@@ Line 310: / Line 312: @@
 	while(1)
 	{
-		i = fscanf(stdin,"%f , %f , %f",&ToLon,&ToLat,&ToAlt);
+		i = scanf("%f , %f , %f",&ToLon,&ToLat,&ToAlt);
 		if (i != 3)
@@ Line 328: / Line 330: @@
 	look_for("</LineString>"); // look for closing </LineString> token
-	return(0);
+	return 0;
 }
@@ Line 474: / Line 476: @@
 	do
 	{
-		if (fgets(pch, size - 1, stdin) == NULL)
+		if (fgets(pch, size, stdin) == NULL)
-			return(0);
+			return 0;
 	}
 	while(buf[0] != '$'); // loop until NMEA valid line read
-	return(1); // line read OK
+	return 1; // line read OK
 }
@@ Line 541: / Line 543: @@
 	point = (int)((bearing + 11.25) / 22.5); // calculate a compas point 0 - 16 for 0 - 360
 	point &= 0x000F; // wrap 16 to 0
-	return( &points[point * 4]);
+	return &points[point * 4];
 }
@@ Line 549: / Line 551: @@
 double Time_to_Sec(int Hours, int Minutes, double Seconds)
 {
-	return(Seconds + ((double)Minutes * 60.0) + ((double)Hours * 3600.0));
+	return Seconds + ((double)Minutes * 60.0) + ((double)Hours * 3600.0);
 }
@@ Line 559: / Line 561: @@
 	if ((Dir == 'N') || (Dir == 'E'))
-		return(Deg);
+		return Deg;
 	else
-		return(-Deg); // Assume 'W' or 'S'
+		return -Deg; // Assume 'W' or 'S'
 }
@@ Line 622: / Line 624: @@
 			Second - BaseSec,LatDeg,LonDeg,Alt,Bearing,deg_to_compass16(Bearing),Distance);
-		return(GPGGA);
+		return GPGGA;
 	}
@@ Line 632: / Line 634: @@
 		fprintf(stderr," Co=%5.1f %.3s Kh=%.1f%",Course,deg_to_compass16(Course),SpeedKn * 1.852);
-		return(GPRMC);
+		return GPRMC;
 	}
@@ Line 639: / Line 641: @@
 	if (i > 0)
 	{ // some fileds converted
-		return(GPVTG);
+		return GPVTG;
 	}
-	return(NONE);
+	return NONE;
 }
@@ Line 686: / Line 688: @@
     }
-	return(0); // normal termination
+	return 0; // normal termination
 }