SIM900 from seedstudio / no internet conection

Hardware Arduino GSM Shield
#1

I have the Shield GPRS from seedstudio:
http://www.seeedstudio.com/depot/GPRS-Shield-V20-p-1379.html
And One Arduino UNO

The simple call, sms run well but I have some problems with the internet conection

#include <SoftwareSerial.h>
#include <String.h>
 
SoftwareSerial mySerial(7, 8);



void setup()
{
  mySerial.begin(19200);               // the GPRS baud rate   
  Serial.begin(19200);    // the GPRS baud rate 
  delay(500);
  SIM900power();
  
}
 
void loop()
{
 
  if (Serial.available())
    switch(Serial.read())
   {
     case 'h':
       SubmitHttpRequest();
       break;

   } 
  if (mySerial.available())
    Serial.write(mySerial.read());
}

 
void SubmitHttpRequest()
{
  String humidity = "1031";
  mySerial.println("AT+CSQ");
  delay(100);
  ShowSerialData();
  mySerial.println("AT+CGATT?");
  delay(100);
  ShowSerialData();
  mySerial.println("AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"");
  delay(1000);
  ShowSerialData();
  mySerial.println("AT+SAPBR=3,1,\"APN\",\"internet\"");
  delay(4000);
  ShowSerialData();
  mySerial.println("AT+SAPBR=1,1");
  delay(2000);
  ShowSerialData();
  mySerial.println("AT+HTTPINIT");
  delay(2000); 
  ShowSerialData();
  mySerial.println("AT+HTTPPARA=\"URL\",\"www.xxx.com/ab/tx.php?h=" + humidity + "\"");
  delay(1000);
  ShowSerialData();
  mySerial.println("AT+HTTPACTION=0");
  delay(10000);
  ShowSerialData();
  mySerial.println("AT+HTTPREAD");
  delay(300);
  ShowSerialData();
  mySerial.println("");
  delay(100);
}
 

 
void ShowSerialData()
{
  while(mySerial.available()!=0)
    Serial.write(mySerial.read());
}

void SIM900power()
// software equivalent of pressing the GSM shield "power" button
{
  digitalWrite(9, HIGH);
  delay(1000);
  digitalWrite(9, LOW);
  delay(5000);
}

Reponse:

+CSQ: 10,0

OK
AT+CGATT?

+CGATT: 0

OK
AT+SAPBR=3,1,"CONTYPE","GPRS"

OK
AT+SAPBR=3,1,"APN","internet"

OK
AT+SAPBR=1,1

ERROR
AT+HTTPINIT

OK
AT+HTTPPARA="URL","www.XXXX.com/ab/tx.php?h=1031"

OK
AT+HTTPACTION=0

OK

+HTTPACTION:0,601,0
AT+HTTPREAD

OK

I have make a lot of search but no response
Thanks for your help

#2

Is the APN parameter the real one you use or have you inserted dummy data?

#3

I stupidly copied the parameters of code that I found :blush: . It depends on my access provider I guess? What needs to be changed and how?

In my provider I find this :
APN Internet
Nom : Free
APN : free
MCC : 208
MNC : 15

By typing the code I figured that the error come from this line ...
mySerial.println("AT+SAPBR=3,1,"APN","internet"");
=>
mySerial.println("AT+SAPBR=3,1,"APN","free"");

I'll test now ... :smiley:

#4

I would expect your parameters to be something like this, depending on your service provider:

AT+SAPBR=3,1,"CONTYPE","GPRS"
AT+SAPBR=3,1,"APN","internet.myprovider.com"
AT+SAPBR=3,1,"USER","web"
AT+SAPBR=3,1,"PWD","web"
AT+SAPBR=1,1
#5

I have only put this and it seems to work :grin:

  mySerial.println("AT+CGATT?");
  delay(100);
  ShowSerialData();
  mySerial.println("AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"");
  delay(1000);
  ShowSerialData();
  mySerial.println("AT+SAPBR=3,1,\"APN\",\"free\"");
  delay(4000);
  ShowSerialData();
  mySerial.println("AT+SAPBR=1,1");

Thanks a lot

#6