Sam Clarke / Mbed 2 deprecated GPS-GPRS_Tracker

An SMS based GPS tracker using the Adafruit Ultimate GPS module http://www.adafruit.com/products/746 and the Seeed Studio GPRS shield (Sim900 chipset) http://www.seeedstudio.com/depot/gprs-shield-p-779.html?cPath=132_134

Dependencies:   GPS MODSERIAL mbed-rtos mbed

SMS based GPS tracker

This is an SMS based GPS tracker using using the Adafruit Ultimate GPS module and the Seeed studio GPRS arduino shield [SIM900 chipset]. The idea of this project is to leverage the free SMS between Virgin mobile prepaid SIM cards in Australia for long distance communication.

Currently the GPRS shield is switched on manually, and should be done about 10 seconds before powering the mbed/GPS in order to disable echo properly during start up. This could easily be fixed by switching the GPRS shield with the mbed at start up, waiting the 10 seconds, set the echo then flush the buffer.

The mbed can read all 160 ASCII chars sent in a message for control.

http://i47.tinypic.com/35alpue.png http://i48.tinypic.com/2mi3y0z.png http://i45.tinypic.com/jkeyvt.png

The Seeed GPRS shield http://www.seeedstudio.com/depot/gprs-shield-p-779.html?cPath=132_134

The Adafruit Ultimate GPS http://www.adafruit.com/products/746

main.cpp

Committer:
SamClarke
Date:
2012-10-08
Revision:
5:3a42b208ac4e
Parent:
4:0e55a4620f5e
Child:
6:32c25fb48fd2

File content as of revision 5:3a42b208ac4e:

#include "mbed.h"
#include "GPS.h"
#include "rtos.h"
#include "MODSERIAL.h"
#include <string>
#include <iostream>

using namespace std;

const string GoogleChunk = "https://maps.google.com.au/maps?q=";
const string GoogleExtras = "&z=20";
char GPRSbuffer[512];
string dump;
int index;
int i = 0;

GPS gps(p9,p10);
MODSERIAL GPRS(p13,p14);                                      // MODSERIAL for rxBufferFlush()
MODSERIAL pc(USBTX,USBRX);

DigitalOut myled1(LED1);
DigitalOut myled2(LED2);
DigitalOut myled3(LED3);
DigitalOut myled4(LED4);

void led_thread(void const *argument)                         // Some light jazz in a thread
{
    while (true) {
        DigitalOut leds[4] = {myled1, myled2, myled3, myled4};
        int pattern[6][4] = {{1,0,0,0},{0,1,0,0},{0,0,1,0},{0,0,0,1},{0,0,1,0},{0,1,0,0}};
        int i=0;
        while(1) {
            leds[0] = pattern[i][0];
            leds[1] = pattern[i][1];
            leds[2] = pattern[i][2];
            leds[3] = pattern[i][3];
            wait(0.2);
            i++;
            i == 6? i=0:0;
        }
    }
}

void sendSms()
{
    // Set message mode to ASCII
    GPRS.printf("AT+CMGF=1\r\n");
    wait(1);
    // Set the phone number
    GPRS.printf("AT+CMGS=\"+61435404829\"\r\n");
    wait(1);
    // Write out the GPS data in a message
    GPRS.printf("Time: %4.2f \nAltitude: %3.2fm\nSpeed: %3.2f Kn\nHeading: %3.2f Deg\nValidity: %c\nFix: %s\nSatellites: %d", gps.time, gps.altitude, gps.speed, gps.heading,gps.validity,gps.fixtype,gps.satellites);
    wait(1);
    // Send it...
    GPRS.putc(0x1A);
    wait(3);
    GPRS.printf("AT+CMGF=1\r\n");
    wait(1);
    GPRS.printf("AT+CMGS=\"+61435404829\"\r\n");
    wait(1);
    GPRS.printf("Find me at....\n %s%f,%f%s", GoogleChunk, gps.latitude, gps.longitude, GoogleExtras);
    wait(1);
    GPRS.putc(0x1A);
    wait(1);
}

void parseSms()
{
    // If theres a char waiting in the MODSERIAL buffer
    while (GPRS.readable()) {
        // Assign it to 'c'
        char c = GPRS.getc();
        // Replace all returns and or line endings with money!
        if (c == '\r' || c == '\n') c = '$';
        // Put it in the array
        GPRSbuffer[i] = c;
        // Repeat if possible
        i++;
    }
    // Uncomment the following to debug

    pc.printf("buffer = %s", GPRSbuffer);


    // If we get an SMS notification....
    if (sscanf(GPRSbuffer, "$$+CMTI: \"SM\",%d", &index)>0) {
        pc.printf("\nSMS recieved @ index [%d]", index);
        // Do the send SMS routine...
        sendSms();
        // Wait for the cascade of \r\nOK\r\n\r\nOK\r\n's from the SMS's to finish
        wait(4);
        // Flush out any left in the serial buffer
        GPRS.rxBufferFlush();
        // Reset the GPRS buffer
        memset(GPRSbuffer, '0', 512);
        // Reset the char counter
        i = 0;
    } 
   if (strncmp(GPRSbuffer, "$$RING",6) == 0) {
        //dump = "fixed";
        GPRS.printf("ATH0\r\n");
        wait(1);
        // Flush any incoming rings in the MODSERIAL buffer
        GPRS.rxBufferFlush();
        pc.printf("\nCall recieved");
        // Do the send SMS routine...
        sendSms();
        // Wait for the cascade of [\r\nOK\r\n][\r\nOK\r\n]'s from the SMS's to finish
        wait(4);
        // Flush out any left in the serial buffer
        GPRS.rxBufferFlush();
        // Reset the GPRS buffer
        memset(GPRSbuffer, '0', 512);
        // Reset the char counter
        i = 0;
    } else {
        GPRS.rxBufferFlush();
        // Reset the GPRS buffer
        memset(GPRSbuffer, '0', 512);
        // Reset the char counter
        i = 0;
        pc.printf("\nWaiting for SMS or call...\n");
    }
}

int main()
{
    pc.baud(115200);
    GPRS.baud(19200);
    Thread thread(led_thread);
    memset(GPRSbuffer, '0', 512);
    pc.printf("I'm Alive...\n");
    // Setup the GPS
    gps.Init();
    // Set the GPRS AT echo off
    GPRS.printf("ATE0\r\n");
    pc.printf("GPRS Echo OFF\n");
    wait(1);
    // Delete all messages on the sim card
    GPRS.printf("AT+CMGDA=\"DEL ALL\"\r\n");
    wait(1);
    pc.printf("Messages Cleared...\n");
    wait(1);
    // Flush out any \r\nOK\r\n's
    GPRS.rxBufferFlush();
    // Get in a while loop
    while (1) {
        // Process any recieved data
        parseSms();
        // Process / check GPS data
        gps.parseData();
    }
}