GPS.h

00001 #include "mbed.h"
00002 
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 #ifdef OPEN_LOG
00048     void start_log(void);
00049     void new_file(void);
00050     void stop_log(void);
00051 #endif    
00052     
00053 private:
00054     float nmea_to_dec(float, char);
00055     float trunc(float v);
00056     void getline();
00057     void format_for_log(void);
00058     
00059     Serial _gps;
00060     char msg[1024];
00061     char bfr[1030];
00062     bool is_logging;
00063 #ifdef OPEN_LOG
00064     Logger _openLog;
00065 #endif
00066     // calculated values
00067     float dec_longitude;
00068     float dec_latitude;
00069     float altitude_ft;
00070     
00071     // GGA - Global Positioning System Fixed Data
00072     float nmea_longitude;
00073     float nmea_latitude;    
00074     float utc_time;
00075     char ns, ew;
00076     int lock;
00077     int satelites;
00078     float hdop;
00079     float msl_altitude;
00080     char msl_units;
00081     
00082     // RMC - Recommended Minimmum Specific GNS Data
00083     char rmc_status;
00084     float speed_k;
00085     float course_d;
00086     int date;
00087     
00088     // GLL
00089     char gll_status;
00090     
00091     // VTG - Course over ground, ground speed
00092     float course_t; // ground speed true
00093     char course_t_unit;
00094     float course_m; // magnetic
00095     char course_m_unit;
00096     char speed_k_unit;
00097     float speed_km; // speek km/hr
00098     char speed_km_unit;
00099 };
00100 
00101 #endif