GPRS module HTTP GET/POST

Usually after this command AT+SAPBR=3,1,"CONTYPE","GPRS" you  enter your "APN", "USR" & "PWD" details also using SAPBR=3,1 etc. These details must match the SIM card / mobile phone provider.

Then it is recommended to check that your device has now received an IP address. Sometimes this is not straight away. Use AT+SAPBR=2,1 to query and this will return your IP address which you should check for confirmation.

Once you have IP address you can enter AT+HTTPINIT, AT+HTTPPARA="CID",1 etc.

Now to use GET you have to include a "?" after the URL to provide your php script with a key=value pairing.

Thus in your case it is something like, AT+HTTPPARA="URL","http://<Public_Ip_Address>:8080/folder/savedata.php?A=1001" where A is the key and 1001 is the value.

Now send the AT+HTTPACTION=0 and you should get a +HTTPACTION: 0,200,1000 response where 200 is the OK and 1000 is the payload size. AT+HTTPREAD will allow you to read the response if it is required.

Hi BigG, thanks to your response, it is very useful to me...

What I still don't understand is:

why do I have to set APN (access point name), USR, PSW, if I don't connect to the Internet using an Access Point?

I want to connect to the Internet using GPRS directly, without passing through a Lan or through a Router which I have to connet to.

Thanks again.

HiBigG,

I got what you wanted to say. We talk about APN,USER,PSW of the Provider of the GPRS sim card.

I've searched these pieces of information on the Internet and I've found: APN= "tre.it", USER=""; PSW=""

then I wrote the following commands, but, as you can see, I cannot get a valid IP address to start the connection:

RDY

+CFUN: 1

+CPIN: READY

Call Ready

SMS Ready

AT

OK

AT+CGATT? 

+CGATT: 1

OK

AT+CGATT=1

OK

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

OK

AT+SAPBR=3,1,"APN","tre.it" 

OK

AT+SAPBR=3,1,"USER","" 

OK

AT+SAPBR=3,1,"PWD","" 

OK

AT+SAPBR=2,1 

+SAPBR: 1,3,"0.0.0.0"

OK

... What am I getting wrong? Thanks.

Hello, no you are not getting anything wrong as far as I can tell. Assuming you have credit on SIM card, are using the right settings and that you have reasonable cellular signal strength etc, then what is happening is that you are waiting for the tre.it AP to assign you an IP address. As noted in my original post, this does not always happen straight away. You could wait awhile (minutes) on some occasions and other times you can get one straight away. You just keep checking every few seconds using AT+SAPBR=2,1

HI BigG

hello i am  also working in sim 800 and whenever i try to update to the http server i am facing these kind of errors mainly

+HTTPACTION: 0,603,0 (Dns error)

+HTTPACTION: 0,601,0 (network error)

+HTTPACTION: 0,604,0 (stack Busy)

i am not getting any idea how to solve it  tried whatever u were telling to  Alessandro Argentieri but i was not able to solve it is there any way to get to know what the problem is by using any other  at commands .

1)how to overcome the stack busy error ?

2)  i got network error (+HTTPACTION: 0,601,0 ) but when i call it picks my call? at that moment.

please help me to sought the error

Thanks in advance

Arun, if I recall from past experience this could have something to do with your server script rather than with device hardware/code. Are you trying to get a large amount of data in return via a server response. If it is stack related you may need to use a chunked data response. Sometime you need to buffer at server side before responding. Did you try a "hello world" test etc. to make sure a basic http request works.

HI BigG

I am able to uplod data to the server but sometimes i get these type of errors which i mentioned earlier.Please look at the issues also.

I am trying to post the data to the server and my buff size will be around  150KB and with some delay i am posting one more data which will be around 30KB

and some times i get this error +HTTPACTION 604 (stack error ) and after that i get one more error is +HTTPACTION 603(dns error) .

Need to see your device and server code as well as know what microcontroller and server type is being used to rule in / rule out probable causes.

Did you search stackoverflow, as a quick search revealed this link gsm - error +HTTPACTION:0,601,0 - Stack Overflow