/** Assemble an NMEA GPVTG message and send it out NMEA USARTs. * NMEA VTG contains course and speed * * \param soln Pointer to gnss_solution struct */ void nmea_gpvtg(const gnss_solution *soln) { /* NMEA Parameters for GPVTG * Ex. * $GPVTG,054.7,T,034.4,M,005.5,N,010.2,K * | | | | | | | | | * Command | 'T' | 'M' | 'N' | 'K' * True Course | Speed (K) | * Mag. course Speed (km/hr) */ float vknots, vkmhr; float x,y,z; x = soln->vel_ned[0]; y = soln->vel_ned[1]; z = soln->vel_ned[2]; float course = atan2(y,x); /* Conversion to magnitue knots */ vknots = MS2KNOTTS(x,y,z); /* Conversion to magnitue km/hr */ vkmhr = MS2KMHR(x,y,z); NMEA_SENTENCE_START(120); NMEA_SENTENCE_PRINTF( "$GPVTG,%05.1f,T," /* Command, course, */ ",M," /* Magnetic Course (omitted) */ "%06.2f,N,%06.2f,K", /* Speed (knots, km/hr) */ course* R2D, vknots, vkmhr); NMEA_SENTENCE_DONE(); }
/** Assemble an NMEA GPRMC message and send it out NMEA USARTs. * NMEA RMC contains minimum GPS data * * \param nav_meas Pointer to navigation_measurement struct. * \param soln Pointer to gnss_solution struct * \param gps_t Pointer to the current GPS Time */ void nmea_gprmc(const navigation_measurement_t *nav_meas, const gnss_solution *soln, const gps_time_t *gps_t) { /* NMEA Parameters * Ex. * $GPRMC,220516,A,5133.82,N,00042.24,W,173.8,231.8,130694,004.2,W*70 * | | | | | | | | | | | | | * Command | | Lat N/S | | | | Date Stamp | W/E | * Time (UTC) | Long W/E | True Course | Cksum * Validity (A-OK) Speed Variation * Variation is ignored as we have no way to maintain that information * currently */ time_t unix_t; struct tm t; unix_t = gps2time(*gps_t); gmtime_r(&unix_t, &t); double frac_s = fmod(gps_t->tow, 1.0); s16 lat_deg = R2D * (soln->pos_llh[0]); double lat_min = MINUTES(soln->pos_llh[0]); s16 lon_deg = R2D * (soln->pos_llh[1]); double lon_min = MINUTES(soln->pos_llh[1]); lat_deg = abs(lat_deg); lon_deg = abs(lon_deg); char lat_dir = soln->pos_llh[0] < 0 ? 'S' : 'N'; char lon_dir = soln->pos_llh[1] < 0 ? 'W' : 'E'; float velocity; float x,y,z; x = soln->vel_ned[0]; y = soln->vel_ned[1]; z = soln->vel_ned[2]; float course = atan2(y,x); /* Conversion to magnitue knots */ velocity = MS2KNOTTS(x,y,z); double az, el; wgsecef2azel(nav_meas[0].sat_pos, soln->pos_ecef, &az, &el); char buf[100]; u8 n = sprintf(buf, "$GPRMC,%02d%02d%06.3f,A," /* Command, Time (UTC), Valid */ "%02d%010.7f,%c,%03d%010.7f,%c," /* Lat/Lon */ "%06.2f,%05.1f," /* Speed, Course */ "%02d%02d%02d," /* Date Stamp */ ",", /* Variation */ t.tm_hour, t.tm_min, t.tm_sec + frac_s, lat_deg, lat_min, lat_dir, lon_deg, lon_min, lon_dir, velocity, course * R2D, t.tm_mday, t.tm_mon, t.tm_year-100); u8 sum = nmea_checksum(buf); sprintf(buf + n, "*%02X\r\n", sum); nmea_output(buf); }
/** Assemble an NMEA GPRMC message and send it out NMEA USARTs. * NMEA RMC contains minimum GPS data * * \param soln Pointer to gnss_solution struct * \param gps_t Pointer to the current GPS Time */ void nmea_gprmc(const gnss_solution *soln, const gps_time_t *gps_t) { /* NMEA Parameters * Ex. * $GPRMC,220516,A,5133.82,N,00042.24,W,173.8,231.8,130694,004.2,W*70 * | | | | | | | | | | | | | * Command | | Lat N/S | | | | Date Stamp | W/E | * Time (UTC) | Long W/E | True Course | Cksum * Validity (A-OK) Speed Variation * Variation is ignored as we have no way to maintain that information * currently */ time_t unix_t; struct tm t; unix_t = gps2time(*gps_t); gmtime_r(&unix_t, &t); double frac_s = fmod(gps_t->tow, 1.0); s16 lat_deg = R2D * (soln->pos_llh[0]); double lat_min = MINUTES(soln->pos_llh[0]); s16 lon_deg = R2D * (soln->pos_llh[1]); double lon_min = MINUTES(soln->pos_llh[1]); lat_deg = abs(lat_deg); lon_deg = abs(lon_deg); char lat_dir = soln->pos_llh[0] < 0 ? 'S' : 'N'; char lon_dir = soln->pos_llh[1] < 0 ? 'W' : 'E'; float velocity; float x,y,z; x = soln->vel_ned[0]; y = soln->vel_ned[1]; z = soln->vel_ned[2]; float course = atan2(y,x); /* Conversion to magnitue knots */ velocity = MS2KNOTTS(x,y,z); NMEA_SENTENCE_START(140); NMEA_SENTENCE_PRINTF( "$GPRMC,%02d%02d%06.3f,A," /* Command, Time (UTC), Valid */ "%02d%010.7f,%c,%03d%010.7f,%c," /* Lat/Lon */ "%06.2f,%05.1f," /* Speed, Course */ "%02d%02d%02d," /* Date Stamp */ ",", /* Variation */ t.tm_hour, t.tm_min, t.tm_sec + frac_s, lat_deg, lat_min, lat_dir, lon_deg, lon_min, lon_dir, velocity, course * R2D, t.tm_mday, t.tm_mon + 1, t.tm_year % 100); NMEA_SENTENCE_DONE(); }
/** Assemble an NMEA GPVTG message and send it out NMEA USARTs. * NMEA VTG contains course and speed * * \param nav_meas Pointer to navigation_measurement struct. * \param soln Pointer to gnss_solution struct */ void nmea_gpvtg(const navigation_measurement_t *nav_meas, const gnss_solution *soln) { /* NMEA Parameters for GPVTG * Ex. * $GPVTG,054.7,T,034.4,M,005.5,N,010.2,K * | | | | | | | | | * Command | 'T' | 'M' | 'N' | 'K' * True Course | Speed (K) | * Mag. course Speed (km/hr) */ double az, el; wgsecef2azel(nav_meas[0].sat_pos, soln->pos_ecef, &az, &el); float vknots, vkmhr; float x,y,z; x = soln->vel_ned[0]; y = soln->vel_ned[1]; z = soln->vel_ned[2]; float course = atan2(y,x); /* Conversion to magnitue knots */ vknots = MS2KNOTTS(x,y,z); /* Conversion to magnitue km/hr */ vkmhr = MS2KMHR(x,y,z); char buf[80]; u8 n = sprintf(buf, "$GPVTG,%05.1f,T," /* Command, course, */ ",M," /* Magnetic Course (omitted) */ "%06.2f,N,%06.2f,K", /* Speed (knots, km/hr) */ course* R2D, vknots, vkmhr); u8 sum = nmea_checksum(buf); sprintf(buf + n, "*%02X\r\n", sum); nmea_output(buf); }