File content as of revision 7:10d3cc37fe4c:

#include <jsonlite.h>
#include "M2XStreamClient.h"

#include "mbed.h"
#include "LM75B.h"  //I2C Temperature Sensor
#include "GPS.h"    //GPS

//------------------------------------------------------------------------------------
// You need to configure these cellular modem / SIM parameters.
// These parameters are ignored for LISA-C200 variants and can be left NULL.
//------------------------------------------------------------------------------------
#include "MDM.h"
//! Set your secret SIM pin here (e.g. "1234"). Check your SIM manual.
#define SIMPIN      NULL
/*! The APN of your network operator SIM, sometimes it is "internet" check your 
    contract with the network operator. You can also try to look-up your settings in 
    google: https://www.google.de/search?q=APN+list */
#define APN         NULL
//! Set the user name for your APN, or NULL if not needed
#define USERNAME    NULL
//! Set the password for your APN, or NULL if not needed
#define PASSWORD    NULL 
//------------------------------------------------------------------------------------

char feedId[] = "81b9fcc5a8585c55ae622488f50d8de0"; // Feed you want to post to
char m2xKey[] = "1e1133cd475954868602c0f7503d4f22"; // Your M2X access key
char streamName[] = "amb_temp"; // Stream you want to post to

char name[] = "<location name>"; // Name of current location of datasource
double latitude = 33.007872;
double longitude = -96.751614; // You can also read those values from a GPS
double elevation = 697.00;
bool location_valid = false;

Client client;
M2XStreamClient m2xClient(&client, m2xKey);

LM75B tmp(SDA,SCL);         // I2C Temperature Sensor

void on_data_point_found(const char* at, const char* value, int index, void* context) {
  printf("Found a data point, index: %d\r\n", index);
  printf("At: %s Value: %s\r\n", at, value);
}

void on_location_found(const char* name,
                       double latitude,
                       double longitude,
                       double elevation,
                       const char* timestamp,
                       int index,
                       void* context) {
  printf("Found a location, index: %d\r\n", index);
  printf("Name: %s  Latitude: %lf  Longitude: %lf\r\n", name, latitude, longitude);
  printf("Elevation: %lf  Timestamp: %s\r\n", elevation, timestamp);
}

int main() {
  MDMSerial mdm;
  GPSI2C gps;
  //mdm.setDebug(4); // enable this for debugging issues 
  if (!mdm.connect(SIMPIN, APN,USERNAME,PASSWORD))
    return -1;
 
  char buf[256];
  
  Timer tmr;
  tmr.reset();
  tmr.start();
  while (true) {
    int ret;
    // extract the location information from the GPS NMEA data
    while ((ret = gps.getMessage(buf, sizeof(buf))) > 0) {
        int len = LENGTH(ret);
        if ((PROTOCOL(ret) == GPSParser::NMEA) && (len > 6)) {
            if (!strncmp("$GPGGA", buf, 6)) {
                char ch;
                if (gps.getNmeaAngle(2,buf,len,latitude) && 
                    gps.getNmeaAngle(4,buf,len,longitude) && 
                    gps.getNmeaItem(6,buf,len,ch) &&
                    gps.getNmeaItem(9,buf,len,elevation)) {
                   printf("GPS Location: %.5f %.5f %.1f %c\r\n", latitude, longitude, elevation, ch); 
                   location_valid = ch == '1' || ch == '2' || ch == '6';
                }
            }
        }
    }
    
    if (tmr.read_ms() > 60000) {
        tmr.reset();
        tmr.start();
        
        // read temp
        sprintf(buf, "%0.2f", tmp.read());
        
        // post temperature
        int response = m2xClient.post(feedId, streamName, buf);
        printf("Post response code: %d\r\n", response);
        if (response == -1) while (true) ;
//#define READING
#ifdef READING
        // read temperature
        response = m2xClient.fetchValues(feedId, streamName, on_data_point_found, NULL);
        printf("Fetch response code: %d\r\n", response);
        if (response == -1) while (true) ;
#endif    
        // update location
        if (location_valid) {
            response = m2xClient.updateLocation(feedId, name, latitude, longitude, elevation);
            printf("updateLocation response code: %d\r\n", response);
            if (response == -1) while (true) ;
        }
#ifdef READING
        // read location
        response = m2xClient.readLocation(feedId, on_location_found, NULL);
        printf("readLocation response code: %d\r\n", response);
        if (response == -1) while (true) ;
#endif
    }
    else {
        delay(100);
    }
  }

  mdm.disconnect();
  mdm.powerOff();
}