Hey guys,

For a project I'm trying to create a GPS-tracker with an Arduino Uno, the Arduino GSM Shield and the Adafruit ultimate GPS-logging shield. So far I've managed to write a few scripts that address parts of the required functionality, however when I add these scripts together I run out of space both memory-wise and ram-wise. Could anyone advise me on how to solve this problem? 

I've added the code below (the combined script) that takes roughly 106% storage space and 120% memory space. I've already tried to comment out the serial println statements, to reduce the library size (which I failed at terribly) and I've also tried to build the configuration with an Arduino Mega. With the Arduino Mega however I ran into problems that first I had to connect ports with jumber cables, and that I could not get the code to run properly on it at all. I've also removed the server url due to privacy concerns. 


[code]
#include <SPI.h>
#include <GSM.h>
#include <Adafruit_GPS.h>
#include <AltSoftSerial.h>
#include <SD.h>
// #include <avr/sleep.h>


AltSoftSerial 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
/* set to true to only log to SD when GPS has a fix, for debugging, keep it false */
#define LOG_FIXONLY true  

// Trying to change to gps logging rate  
#define PMTK_SET_NMEA_UPDATE_10SEC "$PMTK220,10000*2F" // The number after the comma indicates the amount of miliseconds

// this keeps track of whether we're using the interrupt
// off by default!
boolean usingInterrupt = false;
void useInterrupt(boolean); // Func prototype keeps Arduino 0023 happy

// Set the pins used
#define chipSelect 10
#define ledPin 13

File logfile;

// read a Hex value and return the decimal equivalent
uint8_t parseHex(char c) {
  if (c < '0')
    return 0;
  if (c <= '9')
    return c - '0';
  if (c < 'A')
    return 0;
  if (c <= 'F')
    return (c - 'A')+10;
}

// blink out an error code
//void error(uint8_t errno) {
//  /*
//  if (SD.errorCode()) {
//   putstring("SD error: ");
//   Serial.print(card.errorCode(), HEX);
//   Serial.print(',');
//   Serial.println(card.errorData(), HEX);
//   }
//   */
//  while(1) {
//    uint8_t i;
//    for (i=0; i<errno; i++) {
//      digitalWrite(ledPin, HIGH);
//      delay(100);
//      digitalWrite(ledPin, LOW);
//      delay(100);
//    }
//    for (i=errno; i<10; i++) {
//      delay(200);
//    }
//  }
//}

/////////////////////////////////////////

// PIN number SIM card
#define PINNUMBER "0000"

// APN information network provider
#define GPRS_APN       "portalmmm.nl"
#define GPRS_LOGIN     ""
#define GPRS_PASSWORD  ""

// initialize the library instance
GSMClient client;
GPRS gprs;
GSM gsmAccess;

// url and address 
char server[] = " http://gps-kramp.alpha.spheremall.net";
int port = 8084; //Port for Kramp on our server 

// initialize object for file on the SD card
File myFile;
// initialize object for the contents of the file on the SD card
String fileContents;

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);
  // Serial.println("\r\nUltimate GPSlogger Shield");
  pinMode(ledPin, OUTPUT);

  // make sure that the default chip select pin is set to
  // output, even if you don't use it:
  pinMode(10, OUTPUT);

  // see if the card is present and can be initialized:
  //if (!SD.begin(chipSelect, 11, 12, 13)) {
  if (!SD.begin(chipSelect)) {      // if you're using an UNO, you can use this line instead
    // Serial.println("Card init. failed!");
    // error(2);
  }
  char filename[15];
  strcpy(filename, "GPSLOG00.TXT");
  for (uint8_t i = 0; i < 100; i++) {
    filename[6] = '0' + i/10;
    filename[7] = '0' + i%10;
    // create if does not exist, do not open existing, write, sync after write
    if (! SD.exists(filename)) {
      break;
    }
  }

  logfile = SD.open(filename, FILE_WRITE);
  if( ! logfile ) {
    // Serial.print("Couldnt create "); 
    // Serial.println(filename);
    // error(3);
  }
  // Serial.print("Writing to "); 
  // Serial.println(filename);

  // connect to the GPS at the desired rate
  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 logging data, we don't suggest using anything but either RMC only or RMC+GGA
  // to keep the log files at a reasonable size
  // Set the update rate
  GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ);   // 100 millihertz (once every 10 seconds), 1Hz or 5Hz update rate
  // GPS.sendCommand(PMTK_SET_NMEA_UPDATE_10SEC); //Trying to change the update rate to once every 10 seconds
  
  // Turn off updates on antenna status, if the firmware permits it
  GPS.sendCommand(PGCMD_NOANTENNA);

  // the nice thing about this code is you can have a timer0 interrupt go off
  // every 1 millisecond, and read data from the GPS for you. that makes the
  // loop code a heck of a lot easier!
  useInterrupt(true);

  // Serial.println("Ready!");

  //////////////////////

    // initialize serial communications and wait for port to open:
  // Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }

  // Serial.println("Initializing SD card...");
  // On the Ethernet Shield, CS is pin 4. It's set as an output by default.
  // Note that even if it's not used as the CS pin, the hardware SS pin 
  // (10 on most Arduino boards, 53 on the Mega) must be left as an output 
  // or the SD library functions will not work. 
   pinMode(10, OUTPUT);
 
  if (!SD.begin(10)) {
  //  Serial.println("initialization failed!");
    return;
  }
  // Serial.println("initialization done.");
}


// Interrupt is called once a millisecond, looks for any new GPS data, and stores it
SIGNAL(TIMER0_COMPA_vect) {
  char c = GPS.read();
  // if you want to debug, this is a good time to do it!
  #ifdef UDR0
      if (GPSECHO)
        if (c) UDR0 = c;  
      // writing direct to UDR0 is much much faster than Serial.print 
      // but only one character can be written at a time. 
  #endif
}

void useInterrupt(boolean v) {
  if (v) {
    // Timer0 is already used for millis() - we'll just interrupt somewhere
    // in the middle and call the "Compare A" function above
    OCR0A = 0xAF;
    TIMSK0 |= _BV(OCIE0A);
    usingInterrupt = true;
  } 
  else {
    // do not call the interrupt function COMPA anymore
    TIMSK0 &= ~_BV(OCIE0A);
    usingInterrupt = false;
  }
}

void loop() {
  if (! usingInterrupt) {
    // read data from the GPS in the 'main loop'
    char c = GPS.read();
//    // if you want to debug, this is a good time to do it!
//    if (GPSECHO)
//      if (c) Serial.print(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 trying to print out data
    
    // Don't call lastNMEA more than once between parse calls!  Calling lastNMEA 
    // will clear the received flag and can cause very subtle race conditions if
    // new data comes in before parse is called again.
    char *stringptr = GPS.lastNMEA();
    
    if (!GPS.parse(stringptr))   // 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

//    // Sentence parsed! 
//    Serial.println("OK");
//    if (LOG_FIXONLY && !GPS.fix) {
//      Serial.print("No Fix");
//      return;
//    }
//
//    // Rad. lets log it!
//   Serial.println("Log");

    uint8_t stringsize = strlen(stringptr);
    if (stringsize != logfile.write((uint8_t *)stringptr, stringsize))    //write the string to the SD file
        // error(4);
    if (strstr(stringptr, "RMC") || strstr(stringptr, "GGA"))   logfile.flush();
  //  Serial.println();
  }

  /////////////////////////////////

    // open the file for reading:
  myFile = SD.open("test.txt");
  if (myFile) {
   // Serial.println("test.txt:");
 
    // read from the file until there's nothing else in it:
    while (myFile.available()) {
      // Serial.write(myFile.read());
      fileContents += myFile.read();
      fileContents += " ";
      // Serial.println(fileContents);
    }
    // close the file:
    myFile.close();
  } else {
    // if the file didn't open, print an error:
    // Serial.println("error opening test.txt");
  }
  Serial.println(fileContents);

  ///////////////////////////////////////////////////////////


  // Serial.println("Starting Arduino web client.");
  // connection state
  boolean notConnected = true;

  // After starting the modem with GSM.begin()
  // attach the shield to the GPRS network with the APN, login and password
  while (notConnected) {
  // Serial.println("Starting while loop designed to establish a connection with GSM & GPRS");
    if ((gsmAccess.begin(PINNUMBER) == GSM_READY) &
        (gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY)) {
      notConnected = false;
    } else {
      // Serial.println("Not connected");
      delay(1000);
    }
  }

  // Serial.println("connecting...");

  // if you get a connection, report back via serial:
  if (client.connect(server, port)) {
  //  Serial.println("connected");
    
    // Make a HTTP POST request:
    // client.println("POST /test.php HTTP/1.1");
    client.println("POST /v1/gps/locus HTTP/1.1");
    client.println("Host: ");
    client.println("User-Agent: Arduino/1.0");
    client.println("Connection: close");
    client.print("Content-Length: ");
    client.println(fileContents.length());
    client.println();
    client.println(fileContents);
    // Serial.println("Data post should be completed") ;
  } else {
    // if you didn't get a connection to the server:
    // Serial.println("connection failed");
  }
}


/* End code */

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