gps.cpp

00001  
00002 #include "gps.h"
00003 
00004 int dateRef = 90318;
00005  
00006 
00007 Serial gps(D1, D0);
00008 //TextLCD lcd(p11, p12, p15, p16, p29, p30); // rs, e, d4, d5, d6, d7
00009 
00010 void Init()
00011 {
00012     gps.baud(9600);
00013 }
00014 
00015 int getGPS(char* cDataBuffer,float *lat,float *lon,float *tmf,float *spd, int  *dat, char *ns, char *ew, char *stat)
00016 {
00017     char nortSouth, eastWest, status;
00018     int  date,fq, nst;                                     // fix quality, Number of satellites being tracked, 3D fix
00019     float latitude, longitude, timefix, speed,altitude;
00020       
00021     if(strncmp(cDataBuffer,"$GPRMC", 6) == 0) 
00022     {
00023         sscanf(cDataBuffer, "$GPRMC,%f,%c,%f,%c,%f,%c,%f,,%d", &timefix, &status, &latitude, &nortSouth, &longitude, &eastWest, &speed, &date);     
00024         
00025         if (latitude !=0)
00026             *lat = latitude*0.01;
00027         if (longitude != 0)
00028             *lon = longitude*0.01;
00029         
00030         *tmf = timefix;
00031         
00032         *spd = speed;
00033         if (date >= dateRef)
00034             *dat = date;
00035 
00036         if (nortSouth == 'N' | nortSouth == 'S')
00037             *ns = nortSouth;
00038         if (eastWest == 'W' | eastWest == 'E')
00039             *ew = eastWest;
00040         *stat = status;
00041         // pc.printf("GPRMC Fix: %f, Status: %c, Latitude: %f %c, Longitude: %f %c, Speed: %f, Date: %d\n", timefix, status, latitude, nortSouth, longitude, eastWest, speed, date);
00042         // pc.printf("GPRMC Fix: %f, Status: %c, Latitude: %f %c, Longitude: %f %c, Speed: %f, Date: %d\n", *tmf, *stat, *lat, *ns, *lon, *ew, *spd, *dat);
00043         return 0;
00044     }
00045     if(strncmp(cDataBuffer,"$GPGLL", 6) == 0) 
00046     {
00047         sscanf(cDataBuffer, "$GPGLL,%f,%c,%f,%c,%f", &latitude, &nortSouth, &longitude, &eastWest, &timefix);
00048         //pc.printf("%s",cDataBuffer); 
00049         if (latitude !=0)
00050             *lat = latitude * 0.01;
00051             
00052         if (longitude != 0)
00053             *lon = longitude * 0.01;
00054             
00055         *tmf = timefix;
00056         *spd = speed;
00057         
00058         if (nortSouth == 'N' | nortSouth == 'S')
00059             *ns = nortSouth;
00060             
00061         if (eastWest == 'W' | eastWest == 'E')
00062             *ew = eastWest;
00063         return 0;
00064     }
00065    
00066     if(strncmp(cDataBuffer,"$GPGGA", 6) == 0) 
00067     {
00068         sscanf(cDataBuffer, "$GPGGA,%f,%f,%c,%f,%c,%d,%d,%*f,%f", &timefix, &latitude, &nortSouth, &longitude, &eastWest, &fq, &nst, &altitude);
00069         if (latitude !=0)
00070             *lat = latitude * 0.01;
00071             
00072         if (longitude != 0)
00073             *lon = longitude * 0.01;
00074             
00075         //*alt = altitude; 
00076         *tmf = timefix;
00077         
00078         if (nortSouth == 'N' | nortSouth == 'S')
00079             *ns = nortSouth;
00080             
00081         if (eastWest == 'W' | eastWest == 'E')
00082             *ew = eastWest;
00083         return 0;
00084                 
00085     }
00086     return -1;
00087 
00088 
00089 }
00090 
00091 
00092  
00093 int getLatLong(float &lat , float &lon) 
00094 {   
00095     Init();
00096     char Buffer[128],str[7];
00097     char ns, ew, status;
00098     int  date,gpsACK;                                     // fix quality, Number of satellites being tracked, 3D fix
00099     float latitude, longitude, timefix, speed;
00100     memset(Buffer,0,sizeof(Buffer));
00101     date = 0;
00102     latitude = longitude = timefix = speed = 0;
00103     ns = ew = status =0;
00104 
00105     if(gps.readable())
00106     {
00107         gps.gets(Buffer,90);
00108         if(Buffer[0] == '$'){
00109             memcpy(str,Buffer, 6);
00110             //printf("\nrecv: %s\n",str);
00111             gpsACK = getGPS(Buffer, &latitude, &longitude, &timefix, &speed, &date, &ns, &ew, &status);
00112             
00113             }
00114     }    
00115   
00116     if (gpsACK == 0)
00117     {
00118         lat = latitude;
00119         lon = longitude;
00120     }
00121         
00122        
00123      
00124 }
00125  
00126