SIM900 - HTTP / extreme data ratio

Projects Networking, Protocols, and Devices
1

Hello,
i tested transmit data to serve by HTTP. I tested for a four hours maybe and only sometimes i posted request. But data traffic from my SIM card for this time is 300 MB!

I sent only body with content "XXXXXXX,dd.dddddd,X,d.ddddddd" and response is "Xdd,d.dX". I know about header data weight, but also this is extreme data traffic for this small data.

Is problem with SAPR or initHTTP? I call commands (down) in loop every 30-60s. I

//simply code without delay and reading buffer
                GPRS_COM.println("AT+CGATT?");
		GPRS_COM.println("AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"");
		GPRS_COM.println("AT+SAPBR=3,1,\"APN\",\"internet.t-mobile.cz\"");
		GPRS_COM.println("AT+SAPBR=1,1");
		GPRS_COM.println("AT+HTTPINIT");
		GPRS_COM.println("AT+HTTPPARA=\"URL\",\""+String(DEVICE_API)+"/IncomingHandler.ashx?Data=" + data + "\"");
		GPRS_COM.println("AT+HTTPACTION=0");
		GPRS_COM.println("AT+HTTPREAD");
		GPRS_COM.println("AT+HTTPTERM");
		GPRS_COM.println("AT+SAPBR=0,1");

Thanks for help. I use this module http://www.geeetech.com/wiki/index.php/Arduino_GPRS_Shield

2

You need to check to see if only one data byte is being sent in each data packet. This might be happening using the "print" function.

3

Do you know, how can i check this on GSM? And exist another method for send commands to the module?