I am working on the adafruit ultimate GPS logger with GPS_SoftwareSerial_Parsing example and I want to know the type of the array/variable listed below that are used in the code added? Any command can be used for this
GPS.latitude
GPS.lat
// Test code for Adafruit GPS modules using MTK3329/MTK3339 driver
//
// This code shows how to listen to the GPS module in an interrupt
// which allows the program to have more 'freedom' - just parse
// when a new NMEA sentence is available! Then access data when
// desired.
//
// Tested and works great with the Adafruit Ultimate GPS module
// using MTK33x9 chipset
// ------> http://www.adafruit.com/products/746
#include <Adafruit_GPS.h>
#include <SoftwareSerial.h>
// Connect the GPS Power pin to 5V
// Connect the GPS Ground pin to ground
// Connect the GPS TX (transmit) pin to Digital 8
// Connect the GPS RX (receive) pin to Digital 7
// you can change the pin numbers to match your wiring:
SoftwareSerial mySerial(8, 7);
Adafruit_GPS GPS(&mySerial);
// Set GPSECHO to 'false' to turn off echoing the GPS data to the Serial console
// Set to 'true' if you want to debug and listen to the raw GPS sentences
#define GPSECHO true
void setup()
{
// connect at 115200 so we can read the GPS fast enough and echo without dropping chars
// also spit it out
Serial.begin(115200);
delay(5000);
Serial.println("Adafruit GPS library basic parsing test!");
// 9600 NMEA is the default baud rate for Adafruit MTK GPS's- some use 4800
GPS.begin(9600);
// uncomment this line to turn on RMC (recommended minimum) and GGA (fix data) including altitude
GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCGGA);
// uncomment this line to turn on only the "minimum recommended" data
//GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCONLY);
// For parsing data, we don't suggest using anything but either RMC only or RMC+GGA since
// the parser doesn't care about other sentences at this time
// Set the update rate
GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ); // 1 Hz update rate
// For the parsing code to work nicely and have time to sort thru the data, and
// print it out we don't suggest using anything higher than 1 Hz
// Request updates on antenna status, comment out to keep quiet
GPS.sendCommand(PGCMD_ANTENNA);
delay(1000);
// Ask for firmware version
mySerial.println(PMTK_Q_RELEASE);
}
uint32_t timer = millis();
void loop() // run over and over again
{
char c = GPS.read();
// if you want to debug, this is a good time to do it!
if ((c) && (GPSECHO))
//Serial.print("What is this");
Serial.write(c);
// if a sentence is received, we can check the checksum, parse it...
if (GPS.newNMEAreceived()) {
// a tricky thing here is if we print the NMEA sentence, or data
// we end up not listening and catching other sentences!
// so be very wary if using OUTPUT_ALLDATA and trytng to print out data
//Serial.println(GPS.lastNMEA()); // this also sets the newNMEAreceived() flag to false
if (!GPS.parse(GPS.lastNMEA())) // this also sets the newNMEAreceived() flag to false
return; // we can fail to parse a sentence in which case we should just wait for another
}
// approximately every 2 seconds or so, print out the current stats
if (millis() - timer > 2000) {
timer = millis(); // reset the timer
Serial.print("\nTime: ");
if (GPS.hour < 10) { Serial.print('0'); }
Serial.print(GPS.hour, DEC); Serial.print(':');
if (GPS.minute < 10) { Serial.print('0'); }
Serial.print(GPS.minute, DEC); Serial.print(':');
if (GPS.seconds < 10) { Serial.print('0'); }
Serial.print(GPS.seconds, DEC); Serial.print('.');
if (GPS.milliseconds < 10) {
Serial.print("00");
} else if (GPS.milliseconds > 9 && GPS.milliseconds < 100) {
Serial.print("0");
}
Serial.println(GPS.milliseconds);
Serial.print("Date: ");
Serial.print(GPS.day, DEC); Serial.print('/');
Serial.print(GPS.month, DEC); Serial.print("/20");
Serial.println(GPS.year, DEC);
Serial.print("Fix: "); Serial.print((int)GPS.fix);
Serial.print(" quality: "); Serial.println((int)GPS.fixquality);
if (GPS.fix) {
///////////////////////////////////////////////////Check this
Serial.print("Location: ");
Serial.print(GPS.latitude, 0); Serial.print(GPS.lat);
Serial.print(", ");
Serial.print(GPS.longitude, 0); Serial.println(GPS.lon);
Serial.print("**************");
//Serial.print(GPS.lat[0]);
Serial.println(typeof(GPS.lat));
//if (GPS.lat[0]=='2'&& GPS.lat[1]=='4'&& GPS.lat[2]=='1'&& GPS.lat[3]=='1'&& GPS.lat[4]=='N')
//if (GPS.lat[0]=='2'&& GPS.lat[1]=='4'&& GPS.lat[2]=='1'&& GPS.lat[3]=='1'&& GPS.lat[4]=='N')
//{
//Serial.print("done");
//}
//if (GPS.lat == ("2411N")) {Serial.print("done");}
/////////////////////////////////////////////////////////////////////////
Serial.print("Speed (knots): "); Serial.println(GPS.speed);
Serial.print("Angle: "); Serial.println(GPS.angle);
Serial.print("Altitude: "); Serial.println(GPS.altitude);
Serial.print("Satellites: "); Serial.println((int)GPS.satellites);
}
}
}
They are not arrays. GPS.latitude is a nmea_float_t; GPS.lat is just a single character.
You can find it by digging through the library on your PC (grep / grepwin is your friend). I don't have it installed so took a guess and opened Adafruit_GPS.h.
In the class definition, you will find
char lat = 'X'; ///< N/S
and
nmea_float_t latitude; ///< Floating point latitude value in degrees/minutes
///< as received from the GPS (DDMM.MMMM)
A bit more searching reveals that nmea_float_t is just a float; it can be found in NMEA_data.h.
Thanks for the suggestion. I tried it and it works.
One more question, I want to turn ON a LED at a specific geographic location. For example 2410.70N, 5539.97E. I am using if statement but it returns true if I defined check2 variable to be of integer type and if it's defined as float it returns false. I need check2 to be float type can you assist, please. Find the code below.
// Test code for Adafruit GPS modules using MTK3329/MTK3339 driver
//
// This code shows how to listen to the GPS module in an interrupt
// which allows the program to have more 'freedom' - just parse
// when a new NMEA sentence is available! Then access data when
// desired.
//
// Tested and works great with the Adafruit Ultimate GPS module
// using MTK33x9 chipset
// ------> http://www.adafruit.com/products/746
#include <Adafruit_GPS.h>
#include <SoftwareSerial.h>
// Connect the GPS Power pin to 5V
// Connect the GPS Ground pin to ground
// Connect the GPS TX (transmit) pin to Digital 8
// Connect the GPS RX (receive) pin to Digital 7
// you can change the pin numbers to match your wiring:
SoftwareSerial mySerial(8, 7);
Adafruit_GPS GPS(&mySerial);
// Set GPSECHO to 'false' to turn off echoing the GPS data to the Serial console
// Set to 'true' if you want to debug and listen to the raw GPS sentences
#define GPSECHO true
void setup()
{
// connect at 115200 so we can read the GPS fast enough and echo without dropping chars
// also spit it out
Serial.begin(115200);
delay(5000);
Serial.println("Adafruit GPS library basic parsing test!");
// 9600 NMEA is the default baud rate for Adafruit MTK GPS's- some use 4800
GPS.begin(9600);
// uncomment this line to turn on RMC (recommended minimum) and GGA (fix data) including altitude
GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCGGA);
// uncomment this line to turn on only the "minimum recommended" data
//GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCONLY);
// For parsing data, we don't suggest using anything but either RMC only or RMC+GGA since
// the parser doesn't care about other sentences at this time
// Set the update rate
GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ); // 1 Hz update rate
// For the parsing code to work nicely and have time to sort thru the data, and
// print it out we don't suggest using anything higher than 1 Hz
// Request updates on antenna status, comment out to keep quiet
GPS.sendCommand(PGCMD_ANTENNA);
delay(1000);
// Ask for firmware version
mySerial.println(PMTK_Q_RELEASE);
}
uint32_t timer = millis();
void loop() // run over and over again
{
char c = GPS.read();
// if you want to debug, this is a good time to do it!
if ((c) && (GPSECHO))
//Serial.print("What is this");
Serial.write(c);
// if a sentence is received, we can check the checksum, parse it...
if (GPS.newNMEAreceived()) {
// a tricky thing here is if we print the NMEA sentence, or data
// we end up not listening and catching other sentences!
// so be very wary if using OUTPUT_ALLDATA and trytng to print out data
//Serial.println(GPS.lastNMEA()); // this also sets the newNMEAreceived() flag to false
if (!GPS.parse(GPS.lastNMEA())) // this also sets the newNMEAreceived() flag to false
return; // we can fail to parse a sentence in which case we should just wait for another
}
// approximately every 2 seconds or so, print out the current stats
if (millis() - timer > 2000) {
timer = millis(); // reset the timer
Serial.print("\nTime: ");
if (GPS.hour < 10) { Serial.print('0'); }
Serial.print(GPS.hour, DEC); Serial.print(':');
if (GPS.minute < 10) { Serial.print('0'); }
Serial.print(GPS.minute, DEC); Serial.print(':');
if (GPS.seconds < 10) { Serial.print('0'); }
Serial.print(GPS.seconds, DEC); Serial.print('.');
if (GPS.milliseconds < 10) {
Serial.print("00");
} else if (GPS.milliseconds > 9 && GPS.milliseconds < 100) {
Serial.print("0");
}
Serial.println(GPS.milliseconds);
Serial.print("Date: ");
Serial.print(GPS.day, DEC); Serial.print('/');
Serial.print(GPS.month, DEC); Serial.print("/20");
Serial.println(GPS.year, DEC);
Serial.print("Fix: "); Serial.print((int)GPS.fix);
Serial.print(" quality: "); Serial.println((int)GPS.fixquality);
if (GPS.fix) {
///////////////////////////////////////////////////Check this
Serial.print("Location: ");
Serial.print(GPS.latitude, 2); Serial.print(GPS.lat);
Serial.print(", ");
Serial.print(GPS.longitude, 2); Serial.println(GPS.lon);
char check1=GPS.lat;
float check2 =GPS.latitude;
Serial.println("XXXXXX");
Serial.println(check1);
Serial.println(check2);
Serial.println("XXXXXXX");
if (check1=='N'&& check2==2410.70)
{
Serial.println("done :) :) :) :)");
}
//if (GPS.lat == ("2411N")) {Serial.print("done");}
/////////////////////////////////////////////////////////////////////////
Serial.print("Speed (knots): "); Serial.println(GPS.speed);
Serial.print("Angle: "); Serial.println(GPS.angle);
Serial.print("Altitude: "); Serial.println(GPS.altitude);
Serial.print("Satellites: "); Serial.println((int)GPS.satellites);
}
}
}
Never try to compare one float to another just like that; they'll nearly always differ if one (or both) of them is a real-world number. E.g. 2410.70 will in reality be something like 2410.69994. So this one:
will indeed not work, because check2 is pretty much guaranteed to never be 2410.70 even if it's close enough for your standards.
It would be better to do something like this: if (check1=='N'&& (check2 > 2410.69 && check2 < 2410.71))
I can't decide for you what acceptable margins would be.
That wouldn't make sense to begin with since it's really a float value, so let's not go there
