NULL              // DGPS station ID number

};

static const t_nmea_parser rmc_parsers[] = {

	NULL,             // $GPRMC

	parse_time,       // Time

	parse_status,     // A=active, V=void

	parse_lat,        // Latitude,

	parse_lat_hemi,   // N/S

	parse_lon,        // Longitude

	parse_lon_hemi,   // E/W

	parse_speed,      // Speed over ground in knots

	parse_course,     // Track angle in degrees (true)

	NULL,             // Date (DDMMYY)

	NULL,             // Magnetic variation

	NULL              // E/W

};

static const int NUM_OF_UNK_PARSERS = (sizeof(unk_parsers) / sizeof(t_nmea_parser));

static const int NUM_OF_GGA_PARSERS = (sizeof(gga_parsers) / sizeof(t_nmea_parser));

static const int NUM_OF_RMC_PARSERS = (sizeof(rmc_parsers) / sizeof(t_nmea_parser));

// Module variables

static t_sentence_type sentence_type = SENTENCE_UNK;

static bool at_checksum = false;

static unsigned char our_checksum = '$';

static unsigned char their_checksum = 0;

static char token[16];

static int num_tokens = 0;

static unsigned int offset = 0;

static bool active = false;

static char gga_time[7] = "", rmc_time[7] = "";

static char new_time[7];

static uint32_t new_seconds;

static float new_lat;

static float new_lon;

static char new_aprs_lat[9];

static char new_aprs_lon[10];

static float new_course;

static float new_speed;

static float new_altitude;

// Public (extern) variables, readable from other modules

char gps_time[7];       // HHMMSS

uint32_t gps_seconds = 0;   // seconds after midnight

}

/// we do not need to record course

void parse_course(const char *token)

{

	new_course = atof(token);

}

/// will use this to validate pressure readings

void parse_altitude(const char *token)

{

	new_altitude = atof(token);

}

//

// Exported functions

//

/// void zeroing of data. presumably to be called at start

void gps_setup() {

	strcpy(gps_time, "000000");

	strcpy(gps_aprs_lat, "0000.00N");

	strcpy(gps_aprs_lon, "00000.00E");

}

/// MKa GPS transmission parser

void parse_gps_transmission(char c){

	// i think c is the most recent character of transmission and is constantly 

	// tested if terminal character. if terminal then do parse on previous transmission.

	// $--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx

	if(c == '\n') //end of transmission sentence. may need more checks

	{

	}

}

/// process gps transmission 

bool gps_decode(char c)

{

	int ret = false;

	switch(c) {

		case '\r':

		case '\n': // End of sentence

			if (num_tokens && our_checksum == their_checksum) { ///checksum is valid (good transmission)

				#ifdef DEBUG_GPS

				Serial.print(" (OK!) ");

				Serial.print(millis());

				#endif

				// Return a valid position only when we have two rmc and gga

				// messages with the same timestamp.

				switch (sentence_type) {

					case SENTENCE_UNK:

						break;    // Keeps gcc happy

					case SENTENCE_GGA:

						strcpy(gga_time, new_time);

						break;

					case SENTENCE_RMC:

						strcpy(rmc_time, new_time);

						break;

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

 */

#ifndef __GPS_H__

#define __GPS_H__

#include <stdint.h>

#include <stdlib.h>

#include <string.h>

#include <stdbool.h>

extern char gps_time[7];       // HHMMSS

extern uint32_t gps_seconds;   // seconds after midnight

extern char gps_date[7];       // DDMMYY

extern float gps_lat;

extern float gps_lon;

extern char gps_aprs_lat[9];

extern char gps_aprs_lon[10];

extern float gps_course;

extern float gps_speed;

extern float gps_altitude;

void gps_setup();

bool gps_decode(char c);

#endif