Hello! I’m developing a GPS tracker with an arduino nano, sim900a gsm and neo 6m gps module. I have connected all of them and connections are as follows:
GSM ------ NANO
5VR ------ D6
5VT ------ D7
GND ----- GND
VCC ------5V
GPS------ NANO
TX------ RX
5VT ------ D3
GND ----- GND
VCC ------5V
I followed a tutorial online and used the following code
#include "Adafruit_FONA.h"
#include <TinyGPS++.h>
static const uint32_t GPSBaud = 9600;
TinyGPSPlus gps;
#define FONA_RX 6
#define FONA_TX 7
#define FONA_RST 11
// this is a large buffer for replies
char replybuffer[255];
char message[141];
String commands="";
String YourArduinoData="";
#include <SoftwareSerial.h>
SoftwareSerial fonaSS = SoftwareSerial(FONA_TX, FONA_RX);
SoftwareSerial *fonaSerial = &fonaSS;
// HardwareSerial *fonaSerial = &Serial;
// Use this for FONA 800 and 808s
Adafruit_FONA fona = Adafruit_FONA(FONA_RST);
// Use this one for FONA 3G
//Adafruit_FONA_3G fona = Adafruit_FONA_3G(FONA_RST);
uint8_t readline(char *buff, uint8_t maxbuff, uint16_t timeout = 0);
void setup() {
Serial.begin(GPSBaud);
Serial.println(F("FONA SMS caller ID test"));
Serial.println(F("Initializing....(May take 3 seconds)"));
pinMode(13,1);
// make it slow so its easy to read!
fonaSerial->begin(4800);
if (! fona.begin(*fonaSerial)) {
Serial.println(F("Couldn't find FONA"));
while(1);
}
Serial.println(F("FONA is OK"));
// Print SIM card IMEI number.
char imei[16] = {0}; // MUST use a 16 character buffer for IMEI!
uint8_t imeiLen = fona.getIMEI(imei);
if (imeiLen > 0) {
Serial.print("SIM card IMEI: "); Serial.println(imei);
}
fonaSerial->print("AT+CNMI=2,1\r\n"); //set up the FONA to send a +CMTI notification when an SMS is received
Serial.println("FONA Ready");
}
char fonaNotificationBuffer[64]; //for notifications from the FONA
char smsBuffer[250];
void loop() {
getloc();
char* bufPtr = fonaNotificationBuffer;
if (fona.available())
{
int slot = 0;
int charCount = 0;
//Read the notification into fonaInBuffer
do {
*bufPtr = fona.read();
Serial.write(*bufPtr);
delay(1);
} while ((*bufPtr++ != '\n') && (fona.available()) && (++charCount < (sizeof(fonaNotificationBuffer)-1)));
*bufPtr = 0;
if (1 == sscanf(fonaNotificationBuffer, "+CMTI: " FONA_PREF_SMS_STORAGE ",%d", &slot)) {
Serial.print("slot: "); Serial.println(slot);
char callerIDbuffer[32]; //we'll store the SMS sender number in here
if (! fona.getSMSSender(slot, callerIDbuffer, 31)) {
Serial.println("Didn't find SMS message in slot!");
}
Serial.print(F("FROM: ")); Serial.println(callerIDbuffer);
// Retrieve SMS value.
uint16_t smslen;
if (fona.readSMS(slot, smsBuffer, 250, &smslen)) { // pass in buffer and max len!
Serial.println(smsBuffer);
commands=smsBuffer;
Serial.println(commands);
if(commands=="get loc"){
digitalWrite(13,1);
if (!fona.sendSMS(callerIDbuffer, message)) {
Serial.println(F("Failed"));
} else {
Serial.println(F("Sent!"));
digitalWrite(13,0);
}
}
if (fona.deleteSMS(slot)) {
Serial.println(F("OK!"));
}
else {
Serial.println("Deleting Smas from devvice");
Serial.print(F("Couldn't delete SMS in slot ")); Serial.println(slot);
fona.print(F("AT+CMGD=?\r\n"));
}
}
if (fona.deleteSMS(slot)) {
Serial.println(F("OK!"));
}
else {
Serial.println("Deleting Smas from devvice");
Serial.print(F("Couldn't delete SMS in slot ")); Serial.println(slot);
fona.print(F("AT+CMGD=?\r\n"));
}
}
}
}
void getloc(){
// This sketch displays information every time a new sentence is correctly encoded.
if (Serial.available() > 0)
if (gps.encode(Serial.read()))
displayInfo();
if (millis() > 5000 && gps.charsProcessed() < 10)
{
Serial.println(F("No GPS detected: check wiring."));
while(true);
}
}
void displayInfo(){
Serial.println("Location");
Serial.print(F("_Location---"));
Serial.print(gps.location.lat(), 10);
Serial.print(F(","));
Serial.print(gps.location.lng(), 10);
Serial.print(F("_______Date"));
Serial.print(gps.date.month());
Serial.print(F("/"));
Serial.print(gps.date.day());
Serial.print(F("/"));
Serial.print(gps.date.year());
Serial.print(F("--------"));
if (gps.time.hour() < 10) Serial.print(F("0"));
Serial.print(gps.time.hour());
Serial.print(F(":"));
if (gps.time.minute() < 10) Serial.print(F("0"));
Serial.print(gps.time.minute());
Serial.print(F(":"));
if (gps.time.second() < 10) Serial.print(F("0"));
Serial.println();
// char TempString[10]; // Hold The Convert Data
// double val=gps.location.lat();
// dtostrf(val,3,10,TempString);
// // dtostrf( [doubleVar] , [sizeBeforePoint] , [sizeAfterPoint] , [WhereToStoreIt] )
//String YourArduinoData = String(TempString);
//Serial.println(YourArduinoData);
char latitude[18];
char longitude[18];
dtostrf(gps.location.lat(),8,7,latitude);
dtostrf(gps.location.lng(),8,7,longitude);
YourArduinoData = ("https://www.google.com/maps/place/"+ String(latitude) + "," + String(longitude));
YourArduinoData.toCharArray(message, 141);
}
Basically, what it has to do is get the location and when I text the number ‘get loc’ it should send me the google map url of the location. However when I uploaded the sketch to the arduino, it keeps giving me the following error
FONA SMS caller ID test
Initializing....(May take 3 seconds)
Attempting to open comm with ATs
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
---> AT
<---
Timeout: No response to AT... last ditch attempt.
---> AT
<---
---> AT
<---
---> AT
<---
---> ATE0
<---
---> ATE0
<---
Couldn't find FONA
I don’t know what’s wrong? Is it the connections? I’m not sure how to fix this 
A few online forums have mentioned that it may have to be something with the connections but I have connected them and they’re not loose.