GPS.h

00001 #include "mbed.h"
00002 #include "BufferedSerial.h"
00003 #ifndef MBED_GPS_H
00004 #define MBED_GPS_H
00005 
00006 #define NO_LOCK     1
00007 #define NOT_PARSED  2
00008 #define GGA         3
00009 #define GLL         4
00010 #define RMC         5
00011 #define VTG         6
00012 
00013 #define PI (3.141592653589793)
00014 
00015 /**  A GPS interface for reading from a Globalsat EM-406 GPS Module */
00016 class GPS {
00017 public:
00018 
00019     /** Create the GPS interface, connected to the specified serial port
00020      */    
00021     GPS(PinName tx, PinName rx);
00022     
00023     /** Sample the incoming GPS data, returning whether there is a lock
00024      * 
00025      * @return 1 if there was a lock when the sample was taken (and therefore .longitude and .latitude are valid), else 0
00026      */
00027     int sample();
00028     float get_nmea_longitude();
00029     float get_nmea_latitude();
00030     float get_dec_longitude();
00031     float get_dec_latitude();
00032     float get_msl_altitude();
00033     float get_course_t();
00034     float get_course_m();
00035     float get_speed_k();
00036     float get_speed_km();
00037     int get_satelites();
00038     float get_altitude_ft();
00039     
00040     // navigational functions
00041     float calc_course_to(float, float);
00042     double calc_dist_to_mi(float, float);
00043     double calc_dist_to_ft(float, float);
00044     double calc_dist_to_km(float, float);
00045     double calc_dist_to_m(float, float);
00046     
00047     void onInterrupt(){
00048         printf("%d\r\n", _gps.readable());
00049     }
00050 #ifdef OPEN_LOG
00051     void start_log(void);
00052     void new_file(void);
00053     void stop_log(void);
00054 #endif    
00055     
00056 private:
00057     float nmea_to_dec(float, char);
00058     float trunc(float v);
00059     void getline();
00060     void format_for_log(void);
00061     
00062     BufferedSerial _gps;
00063     char msg[1024];
00064     char bfr[1030];
00065     bool is_logging;
00066 #ifdef OPEN_LOG
00067     Logger _openLog;
00068 #endif
00069     // calculated values
00070     float dec_longitude;
00071     float dec_latitude;
00072     float altitude_ft;
00073     
00074     // GGA - Global Positioning System Fixed Data
00075     float nmea_longitude;
00076     float nmea_latitude;    
00077     float utc_time;
00078     char ns, ew;
00079     int lock;
00080     int satelites;
00081     float hdop;
00082     float msl_altitude;
00083     char msl_units;
00084     
00085     // RMC - Recommended Minimmum Specific GNS Data
00086     char rmc_status;
00087     float speed_k;
00088     float course_d;
00089     int date;
00090     
00091     // GLL
00092     char gll_status;
00093     
00094     // VTG - Course over ground, ground speed
00095     float course_t; // ground speed true
00096     char course_t_unit;
00097     float course_m; // magnetic
00098     char course_m_unit;
00099     char speed_k_unit;
00100     float speed_km; // speek km/hr
00101     char speed_km_unit;
00102 };
00103 
00104 #endif