Port of Arduino TinyGPS library to mbed. Added extra methods to flag receipt/parsing of particular sentences.

Dependencies:   gnss

Fork of TinyGPS by Michael Shimniok

Files at this revision

API Documentation at this revision

Comitter:
shimniok
Date:
Wed Apr 27 19:21:28 2011 +0000
Child:
1:f522b8bdf987
Commit message:
Initial release

Changed in this revision

TinyGPS.cpp Show annotated file Show diff for this revision Revisions of this file
TinyGPS.h Show annotated file Show diff for this revision Revisions of this file
types.h Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TinyGPS.cpp	Wed Apr 27 19:21:28 2011 +0000
@@ -0,0 +1,297 @@
+/*
+  TinyGPS - a small GPS library for Arduino providing basic NMEA parsing
+  Copyright (C) 2008-9 Mikal Hart
+  All rights reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+  
+  Ported to mbed by Michael Shimniok http://www.bot-thoughts.com/
+*/
+
+#include "TinyGPS.h"
+
+#define _GPRMC_TERM   "GPRMC"
+#define _GPGGA_TERM   "GPGGA"
+#define _GPGSV_TERM   "GPGSV"
+
+TinyGPS::TinyGPS()
+:  _time(GPS_INVALID_TIME)
+,  _date(GPS_INVALID_DATE)
+,  _latitude(GPS_INVALID_ANGLE)
+,  _longitude(GPS_INVALID_ANGLE)
+,  _altitude(GPS_INVALID_ALTITUDE)
+,  _speed(GPS_INVALID_SPEED)
+,  _course(GPS_INVALID_ANGLE)
+,  _hdop(0)
+,  _sat_count(0)
+,  _last_time_fix(GPS_INVALID_FIX_TIME)
+,  _last_position_fix(GPS_INVALID_FIX_TIME)
+,  _parity(0)
+,  _is_checksum_term(false)
+,  _sentence_type(_GPS_SENTENCE_OTHER)
+,  _term_number(0)
+,  _term_offset(0)
+,  _gps_data_good(false)
+,  _rmc_ready(false)
+,  _gga_ready(false)
+,  _gsv_ready(false)
+#ifndef _GPS_NO_STATS
+,  _encoded_characters(0)
+,  _good_sentences(0)
+,  _failed_checksum(0)
+#endif
+{
+  _term[0] = '\0';
+}
+
+//
+// public methods
+//
+
+bool TinyGPS::encode(char c)
+{
+  bool valid_sentence = false;
+
+  ++_encoded_characters;
+  switch(c)
+  {
+  case ',': // term terminators
+    _parity ^= c;
+  case '\r':
+  case '\n':
+  case '*':
+    if (_term_offset < sizeof(_term))
+    {
+      _term[_term_offset] = 0;
+      valid_sentence = term_complete();
+    }
+    ++_term_number;
+    _term_offset = 0;
+    _is_checksum_term = c == '*';
+    return valid_sentence;
+
+  case '$': // sentence begin
+    _term_number = _term_offset = 0;
+    _parity = 0;
+    _sentence_type = _GPS_SENTENCE_OTHER;
+    _is_checksum_term = false;
+    _gps_data_good = false;
+    return valid_sentence;
+  }
+
+  // ordinary characters
+  if (_term_offset < sizeof(_term) - 1)
+    _term[_term_offset++] = c;
+  if (!_is_checksum_term)
+    _parity ^= c;
+
+  return valid_sentence;
+}
+
+#ifndef _GPS_NO_STATS
+void TinyGPS::stats(unsigned long *chars, unsigned short *sentences, unsigned short *failed_cs)
+{
+  if (chars) *chars = _encoded_characters;
+  if (sentences) *sentences = _good_sentences;
+  if (failed_cs) *failed_cs = _failed_checksum;
+}
+#endif
+
+//
+// internal utilities
+//
+int TinyGPS::from_hex(char a) 
+{
+  if (a >= 'A' && a <= 'F')
+    return a - 'A' + 10;
+  else if (a >= 'a' && a <= 'f')
+    return a - 'a' + 10;
+  else
+    return a - '0';
+}
+
+unsigned long TinyGPS::parse_decimal()
+{
+  char *p = _term;
+  bool isneg = *p == '-';
+  if (isneg) ++p;
+  unsigned long ret = 100UL * gpsatol(p);
+  while (gpsisdigit(*p)) ++p;
+  if (*p == '.')
+  {
+    if (gpsisdigit(p[1]))
+    {
+      ret += 10 * (p[1] - '0');
+      if (gpsisdigit(p[2]))
+        ret += p[2] - '0';
+    }
+  }
+  return isneg ? -ret : ret;
+}
+
+unsigned long TinyGPS::parse_degrees()
+{
+  char *p;
+  unsigned long left = gpsatol(_term);
+  unsigned long tenk_minutes = (left % 100UL) * 10000UL;
+  for (p=_term; gpsisdigit(*p); ++p);
+  if (*p == '.')
+  {
+    unsigned long mult = 1000;
+    while (gpsisdigit(*++p))
+    {
+      tenk_minutes += mult * (*p - '0');
+      mult /= 10;
+    }
+  }
+  return (left / 100) * 100000 + tenk_minutes / 6;
+}
+
+// Processes a just-completed term
+// Returns true if new sentence has just passed checksum test and is validated
+bool TinyGPS::term_complete()
+{
+  if (_is_checksum_term)
+  {
+    byte checksum = 16 * from_hex(_term[0]) + from_hex(_term[1]);
+    if (checksum == _parity)
+    {
+      if (_gps_data_good || 1) // I want to use the thing in demo mode
+      {
+#ifndef _GPS_NO_STATS
+        ++_good_sentences;
+#endif
+        _last_time_fix = _new_time_fix;
+        _last_position_fix = _new_position_fix;
+
+        switch(_sentence_type)
+        {
+        case _GPS_SENTENCE_GPRMC:
+          _time      = _new_time;
+          _date      = _new_date;
+          _latitude  = _new_latitude;
+          _longitude = _new_longitude;
+          _speed     = _new_speed;
+          _course    = _new_course;
+          _rmc_ready = true;
+          break;
+        case _GPS_SENTENCE_GPGGA:
+          _altitude  = _new_altitude;
+          _time      = _new_time;
+          _latitude  = _new_latitude;
+          _longitude = _new_longitude;
+          _gga_ready = true;
+          _hdop      = _new_hdop;
+          _sat_count = _new_sat_count;
+        case _GPS_SENTENCE_GPGSV:
+          _gsv_ready = true;
+          break;
+        }
+
+        return true;
+      }
+    }
+
+#ifndef _GPS_NO_STATS
+    else
+      ++_failed_checksum;
+#endif
+    return false;
+  }
+
+  // the first term determines the sentence type
+  if (_term_number == 0)
+  {
+    if (!gpsstrcmp(_term, _GPRMC_TERM))
+      _sentence_type = _GPS_SENTENCE_GPRMC;
+    else if (!gpsstrcmp(_term, _GPGGA_TERM))
+      _sentence_type = _GPS_SENTENCE_GPGGA;
+    else if (!gpsstrcmp(_term, _GPGSV_TERM))
+      _sentence_type = _GPS_SENTENCE_GPGSV;
+    else
+      _sentence_type = _GPS_SENTENCE_OTHER;
+    return false;
+  }
+
+  if (_sentence_type != _GPS_SENTENCE_OTHER && _term[0])
+  switch((_sentence_type == _GPS_SENTENCE_GPGGA ? 200 : 100) + _term_number)
+  {
+    case 101: // Time in both sentences
+    case 201:
+      _new_time = parse_decimal();
+      _new_time_fix = millis();
+      break;
+    case 102: // GPRMC validity
+      _gps_data_good = _term[0] == 'A';
+      break;
+    case 103: // Latitude
+    case 202:
+      _new_latitude = parse_degrees();
+      _new_position_fix = millis();
+      break;
+    case 104: // N/S
+    case 203:
+      if (_term[0] == 'S')
+        _new_latitude = -_new_latitude;
+      break;
+    case 105: // Longitude
+    case 204:
+      _new_longitude = parse_degrees();
+      break;
+    case 106: // E/W
+    case 205:
+      if (_term[0] == 'W')
+        _new_longitude = -_new_longitude;
+      break;
+    case 107: // Speed (GPRMC)
+      _new_speed = parse_decimal();
+      break;
+    case 108: // Course (GPRMC)
+      _new_course = parse_decimal();
+      break;
+    case 109: // Date (GPRMC)
+      _new_date = gpsatol(_term);
+      break;
+    case 206: // Fix data (GPGGA)
+      _gps_data_good = _term[0] > '0';
+      break;
+    case 207: // Number of satelites tracked (GPGGA)
+      _new_sat_count = parse_decimal();
+      break;
+    case 208: // Horizontal Dilution of Position (GPGGA)
+      _new_hdop = parse_decimal();
+      break;
+    case 209: // Altitude (GPGGA)
+      _new_altitude = parse_decimal();
+      break;
+  } /* switch */
+
+  return false;
+}
+
+long TinyGPS::gpsatol(const char *str)
+{
+  long ret = 0;
+  while (gpsisdigit(*str))
+    ret = 10 * ret + *str++ - '0';
+  return ret;
+}
+
+int TinyGPS::gpsstrcmp(const char *str1, const char *str2)
+{
+  while (*str1 && *str1 == *str2)
+    ++str1, ++str2;
+  return *str1;
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TinyGPS.h	Wed Apr 27 19:21:28 2011 +0000
@@ -0,0 +1,261 @@
+/*
+  TinyGPS - a small GPS library for Arduino providing basic NMEA parsing
+  Copyright (C) 2008-9 Mikal Hart
+  All rights reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+  
+  Ported to mbed by Michael Shimniok
+*/
+
+#include "mbed.h"
+#include "types.h"
+
+#ifndef TinyGPS_h
+#define TinyGPS_h
+
+#define _GPS_VERSION 9 // software version of this library
+#define _GPS_MPH_PER_KNOT 1.15077945
+#define _GPS_MPS_PER_KNOT 0.51444444
+#define _GPS_KMPH_PER_KNOT 1.852
+#define _GPS_MILES_PER_METER 0.00062137112
+#define _GPS_KM_PER_METER 0.001
+//#define _GPS_NO_STATS
+
+class TinyGPS
+{
+  public:
+  
+    /** Create a new GPS parsing object for parsing NMEA sentences
+     */
+    TinyGPS();
+    
+    /** Parse a single character received from GPS
+     *
+     * @param c is the character received from the GPS
+     * @returns true if processing ok
+     */
+    bool encode(char c);
+    
+    /** Shorthand operator for encode()
+     */
+    TinyGPS &operator << (char c) {encode(c); return *this;}
+    
+    /** Return lat/long in hundred thousandths of a degree and age of fix in milliseconds
+     * @returns latitude is the latitude of the most recent fix that was parsed
+     * @returns longitude is the longitude of the most recent fix that was parsed
+     * @returns fix_age is the age of the fix (if available from the NMEA sentences being parsed)
+     */
+    inline void get_position(long *latitude, long *longitude, unsigned long *fix_age = 0)
+    {
+      if (latitude) *latitude = _latitude;
+      if (longitude) *longitude = _longitude;
+      if (fix_age) *fix_age = _last_position_fix == GPS_INVALID_FIX_TIME ? 
+        GPS_INVALID_AGE : millis() - _last_position_fix;
+    }
+
+    /** Return the date and time from the parsed NMEA sentences
+     *
+     * @returns date as an integer value
+     * @returns time as an integer value
+     * @returns fix_age in milliseconds if available
+     */
+    inline void get_datetime(unsigned long *date, unsigned long *time, unsigned long *fix_age = 0)
+    {
+      if (date) *date = _date;
+      if (time) *time = _time;
+      if (fix_age) *fix_age = _last_time_fix == GPS_INVALID_FIX_TIME ? 
+        GPS_INVALID_AGE : millis() - _last_time_fix;
+    }
+
+    /** signed altitude in centimeters (from GPGGA sentence)
+     * @returns altitude in centimeters, integer
+     */
+    inline long altitude() { return _altitude; }
+
+    /** course in last full GPRMC sentence in 100th of a degree
+     * @returns course as an integer, 100ths of a degree
+     */
+    inline unsigned long course() { return _course; }
+    
+    /** speed in last full GPRMC sentence in 100ths of a knot
+     * @returns speed in 100ths of a knot
+     */
+    unsigned long speed() { return _speed; }
+
+    /* horizontal dilution of position in last full GPGGA sentence in 100ths
+     * @returns hdop in 100ths
+     */
+    unsigned long hdop() { return _hdop; }
+
+    /** number of satellites tracked in last full GPGGA sentence
+     * @returns number of satellites tracked 
+     */
+    unsigned long sat_count() { return _sat_count; }
+
+#ifndef _GPS_NO_STATS
+    void stats(unsigned long *chars, unsigned short *good_sentences, unsigned short *failed_cs);
+#endif
+
+    /** returns position as double precision
+     *
+     * @returns latitude as double precision
+     * @returns longitude as double precision
+     * @returns fix age in milliseconds if available
+     */
+    inline void f_get_position(double *latitude, double *longitude, unsigned long *fix_age = 0)
+    {
+      long lat, lon;
+      get_position(&lat, &lon, fix_age);
+      *latitude = lat / 100000.0;
+      *longitude = lon / 100000.0;
+    }
+
+    /** Convert date and time of last parsed sentence to integers
+     *
+     * @returns year
+     * @returns month
+     * @returns day of month
+     * @returns hour
+     * @returns minute
+     * @returns second
+     * @returns hundreths
+     * @returns fix_age in milliseconds if available
+     */
+    inline void crack_datetime(int *year, byte *month, byte *day, 
+      byte *hour, byte *minute, byte *second, byte *hundredths = 0, unsigned long *fix_age = 0)
+    {
+      unsigned long date, time;
+      get_datetime(&date, &time, fix_age);
+      if (year) 
+      {
+        *year = date % 100;
+        *year += *year > 80 ? 1900 : 2000;
+      }
+      if (month) *month = (date / 100) % 100;
+      if (day) *day = date / 10000;
+      if (hour) *hour = time / 1000000;
+      if (minute) *minute = (time / 10000) % 100;
+      if (second) *second = (time / 100) % 100;
+      if (hundredths) *hundredths = time % 100;
+    }
+
+    /** returns altitude as a float
+    */
+    inline double f_altitude()    { return altitude() / 100.0; }
+    
+    /** returns course as a float
+    */
+    inline double f_course()      { return course() / 100.0; }
+    
+    /** returns speed in knots as a float
+    */
+    inline double f_speed_knots() { return speed() / 100.0; }
+    
+    /** returns speed in mph as a float 
+    */
+    inline double f_speed_mph()   { return _GPS_MPH_PER_KNOT * f_speed_knots(); }
+    
+    /** returns speed in meters per second as a float
+    */
+    inline double f_speed_mps()   { return _GPS_MPS_PER_KNOT * f_speed_knots(); }
+    
+    /** returns speed in km per hour as a float
+    */
+    inline double f_speed_kmph()  { return _GPS_KMPH_PER_KNOT * f_speed_knots(); }
+    
+    /** returns hdop as a float
+    */
+    inline double f_hdop()      { return hdop() / 100.0; }
+
+    /** @returns library version
+    */
+    static int library_version() { return _GPS_VERSION; }
+
+    /** determine if RMC sentence parsed since last reset_ready()
+     */
+    inline bool rmc_ready() { return _rmc_ready; }
+
+    /** determine if GGA sentence parsed since last reset_ready()
+     */
+    inline bool gga_ready() { return _gga_ready; }
+
+    /** determine if GSV sentence parsed since last reset_ready()
+     */
+    inline bool gsv_ready() { return _gsv_ready; }
+    
+    /** Reset the ready flags for all the parsed sentences
+     */
+    inline void reset_ready() { _gsv_ready = _rmc_ready = _gga_ready = false; }
+
+    enum {GPS_INVALID_AGE = 0xFFFFFFFF, GPS_INVALID_ANGLE = 999999999, GPS_INVALID_ALTITUDE = 999999999, GPS_INVALID_DATE = 0,
+      GPS_INVALID_TIME = 0xFFFFFFFF, GPS_INVALID_SPEED = 999999999, GPS_INVALID_FIX_TIME = 0xFFFFFFFF};
+
+private:
+    enum {_GPS_SENTENCE_GPGGA, _GPS_SENTENCE_GPRMC, _GPS_SENTENCE_GPGSV, _GPS_SENTENCE_OTHER};
+    
+    // properties
+    unsigned long _time, _new_time;
+    unsigned long _date, _new_date;
+    long _latitude, _new_latitude;
+    long _longitude, _new_longitude;
+    long _altitude, _new_altitude;
+    unsigned long  _speed, _new_speed;
+    unsigned long  _course, _new_course;
+    unsigned long  _hdop, _new_hdop;
+    unsigned int _sat_count, _new_sat_count;
+    unsigned long _last_time_fix, _new_time_fix;
+    unsigned long _last_position_fix, _new_position_fix;
+
+    // parsing state variables
+    byte _parity;
+    bool _is_checksum_term;
+    char _term[15];
+    byte _sentence_type;
+    byte _term_number;
+    byte _term_offset;
+    bool _gps_data_good;
+    bool _rmc_ready;
+    bool _gga_ready;
+    bool _gsv_ready;
+
+#ifndef _GPS_NO_STATS
+    // statistics
+    unsigned long _encoded_characters;
+    unsigned short _good_sentences;
+    unsigned short _failed_checksum;
+    unsigned short _passed_checksum;
+#endif
+
+    // internal utilities
+    int from_hex(char a);
+    unsigned long parse_decimal();
+    unsigned long parse_degrees();
+    bool term_complete();
+    bool gpsisdigit(char c) { return c >= '0' && c <= '9'; }
+    long gpsatol(const char *str);
+    int gpsstrcmp(const char *str1, const char *str2);
+};
+
+// Arduino 0012 workaround
+#undef int
+#undef char
+#undef long
+#undef byte
+#undef double
+#undef abs
+#undef round 
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/types.h	Wed Apr 27 19:21:28 2011 +0000
@@ -0,0 +1,7 @@
+#ifndef __TYPES_H
+#define __TYPES_H
+
+typedef char byte;
+typedef int millis;
+
+#endif
\ No newline at end of file