A cellular solution similar to the Arduino code below would be good. Also, we need not focus only on Ubidots. It just seemed like a good place to start.
I purchased two Xadow GPS mods and would really like to make GPS trackers out of them.
[code]/* This is a simple program to connect the LinkIt ONE to my favorite Internet of Things (IOT) data streaming service - Ubitdots.
Chip McClelland - Cellular Data Logger
BSD license, Please keep my name in any redistribution
Requirements:
- Account on Ubidots. http://www.ubidots.com
- Seedstudio LinkIt ONE - http://www.seeedstudio.com/wiki/LinkIt_ONE
Please note this is just the start - uploading only a single data point. More to come but as your project may
diverge from mine, this may be all you need to get started. Good luck.
This code will be part of a larger project to build a connected Air Quality Sensor -
- Project documentation here: http://triembed.org/blog/?page_id=736
- GitHub repo here: https://github.com/chipmc/AirQualitySensorProject
Updated for v3 - added a GPS “Context” the the battery voltage so Ubidots will
display the location of your LinkIt ONE on a map widget.
Enjoy! And comments welcome on the TriEmbed Blog above
***********************************************************************************/
#include <LGPS.h> // LinkIt GPS Library
#include <LBattery.h> // Want to be able to read the battery charge level
#include <LGPRS.h> //include the base GPRS library
#include <LGPRSClient.h> //include the ability to Post and Get information using HTTP
// These are the variables you will want to change based on your IOT data streaming account / provider
char action[] = "POST "; // Edit to build your command - "GET ", "POST ", "HEAD ", "OPTIONS " - note trailing space
char server[] = “things.ubidots.com”;
char path[] = “/api/v1.6/variables/xxxxxxxxxxxxxxxx/values”; // Edit Path to include you source key
char token[] = “xxxxxxxxxxxxxxxxxxxx”; // Edit to insert you API Token
int port = 80; // HTTP
// Here are the program variables
int num; // part of the length calculation
String le; // length of the payload in characters
String var; // This is the payload or JSON request
unsigned long ReportingInterval = 20000; // How often do you want to update the IOT site in milliseconds
unsigned long LastReport = 0; // When was the last time you reported
const int ledPin = 13; // Light to blink when program terminates
String Location = “”; // Will build the Location string here
// Create instantiations of the GPRS and GPS functions
LGPRSClient globalClient; // See this support topic from Mediatek - http://labs.mediatek.com/forums/posts/list/75.page
gpsSentenceInfoStruct info; // instantiate
void setup()
{
Serial.begin(19200); // setup Serial port
LGPS.powerOn(); // Start the GPS first as it takes time to get a fix
Serial.println(“GPS Powered on, and waiting …”);
Serial.println(“Attach to GPRS network”); // Attach to GPRS network - need to add timeout
while (!LGPRS.attachGPRS(“internet2.voicestream.com”,"","")) { //attachGPRS(const char *apn, const char *username, const char *password);
delay(500);
}
LGPRSClient client; //Client has to be initiated after GPRS is established with the correct APN settings - see above link
globalClient = client; // Again this is a temporary solution described in support forums
}
void loop(){
if (globalClient.available()) {// if there are incoming bytes available from the server
char c = globalClient.read(); // read them and print them:
Serial.print©;
}
if (millis() >= LastReport + ReportingInterval) { // Section to report - will convert to a function on next rev
String value = String(LBattery.level());
LGPS.getData(&info); // Get a GPS fix
if (ParseLocation((const char*)info.GPGGA)) { // This is where we break out needed location information
Serial.print(“Location is: “);
Serial.println(Location); // This is the format needed by Ubidots
}
if (Location.length()==0) {
var=”{“value”:”+ value + “}”; //Build the JSON packet without GPS info
}
else {
var="{“value”:"+ value + “, “context”:”+ Location + “}”; // with GPS info
}
num=var.length(); // How long is the payload
le=String(num); //this is to calcule the length of var
Serial.print(“Connect to “); // For the console - show you are connecting
Serial.println(server);
if (globalClient.connect(server, port)){ // if you get a connection, report back via serial:
Serial.println(“connected”); // Console monitoring
Serial.print(action); // These commands build a JSON request for Ubidots but fairly standard
Serial.print(path); // specs for this command here: http://ubidots.com/docs/api/index.html
Serial.println(” HTTP/1.1”);
Serial.println(F(“Content-Type: application/json”));
Serial.print(F("Content-Length: "));
Serial.println(le);
Serial.print(F("X-Auth-Token: "));
Serial.println(token);
Serial.print(F(“Host: “));
Serial.println(server);
Serial.println();
Serial.println(var); // The payload defined above
Serial.println();
Serial.println((char)26); //This terminates the JSON SEND with a carriage return
globalClient.print(action); // These commands build a JSON request for Ubidots but fairly standard
globalClient.print(path); // specs for this command here: http://ubidots.com/docs/api/index.html
globalClient.println(” HTTP/1.1”);
globalClient.println(F(“Content-Type: application/json”));
globalClient.print(F("Content-Length: "));
globalClient.println(le);
globalClient.print(F("X-Auth-Token: "));
globalClient.println(token);
globalClient.print(F("Host: "));
globalClient.println(server);
globalClient.println();
globalClient.println(var); // The payload defined above
globalClient.println();
globalClient.println((char)26); //This terminates the JSON SEND with a carriage return
LastReport = millis();
}
}
}
boolean ParseLocation(const char* GPGGAstr)
// Refer to http://www.gpsinformation.org/dale/nmea.htm#GGA
// Sample data: $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4,M,46.9,M,*47
{
char latarray[6];
char longarray[6];
int index = 0;
Serial.println(GPGGAstr);
Serial.print("Fix Quality: “);
Serial.println(GPGGAstr[43]);
if (GPGGAstr[43]==‘0’) { // This is the place in the sentence that shows Fix Quality 0 means no fix
Serial.println(“No GPS Fix”);
Location = “”; // No fix then no Location string
return 0;
}
String GPSstring = String(GPGGAstr);
for (int i=20; i<=26; i++) { // We have to jump through some hoops here
latarray[index] = GPGGAstr[i]; // we need to pick out the minutes from the char array
index++;
}
float latdms = atof(latarray); // and convert them to a float
float lattitude = latdms/60; // and convert that to decimal degrees
String lattstring = String(lattitude);// Then put back into a string
Location = “{“lat”:”;
if(GPGGAstr[28] == ‘S’) Location = Location + “-”;
Location += GPSstring.substring(18,20) + “.” + lattstring.substring(2,4);
index = 0;
for (int i=33; i<=38; i++) { // And do the same thing for longitude
longarray[index] = GPGGAstr[i]; // the good news is that the GPS data is fixed column
index++;
}
float longdms = atof(longarray); // and convert them to a float
float longitude = longdms/60; // and convert that to decimal degrees
String longstring = String(longitude);// Then put back into a string
Location += " ,“lng”:”;
if(GPGGAstr[41] == ‘W’) Location = Location + “-”;
if(GPGGAstr[30] == ‘0’) {
Location = Location + GPSstring.substring(31,33) + “.” + longstring.substring(2,4) + “}”;
}
else {
Location = Location + GPSstring.substring(30,33) + “.” + longstring.substring(2,4) + “}”;
}
return 1;
}[/code]
