Using the GSM Module for Internet Connection

Education May 23, 2023 Add to Reading List

Internet connection is also required in electronic systems designed with microcontroller. We may need an internet connection, especially when designing IoT systems or for simpler systems.

There are several alternatives when we need internet connection. These alternatives are wifi and LAN connection. However, if we want to design a physically smaller system and the amount of data we will receive and send is slightly lower, then we may consider connecting a GSM module to the microcontroller.

We can connect the microcontroller system to the internet with a SIM card that we will insert into the GSM module.

In this article, we will list the "AT" commands as in the applications we made with the Wifi module.

On our site, we can also use the RX and TX connection type we used in Wifi and bluetooth applications for the GSM module.

Here are some basic internet related AT commands and explanations of GSM module:

AT+SAPBR=3,1,"Contype","GPRS"
Description: Sets the type of Internet connection to GPRS.
Example usage: AT+SAPBR=3,1,"Contype","GPRS"

AT+SAPBR=1.1
Description: Opens the Internet connection.
Example usage: AT+SAPBR=1.1

AT+HTTPINIT
Description: Initiates the HTTP connection.
Example usage: AT+HTTPINIT

AT+HTTPPARA="CID",1
Description: Sets the connection ID for the HTTP connection.
Example usage: AT+HTTPPARA="CID",1

AT+HTTPPARA="URL","http://www.example.com"
Description: Sets the destination URL.
Example usage: AT+HTTPPARA="URL","http://www.example.com"

AT+HTTPDATA=<data_length>,<wait_time>
Description: Prepares for data transmission.
Example usage: AT+HTTPDATA=50.10000 (10 second wait time for 50 bytes of data)

AT+HTTPACTION=<action_code>
Description: Performs the HTTP operation (GET: 0, POST: 1, HEAD: 2).
Example usage: AT+HTTPACTION=0 (performs GET request)

AT+HTTPREAD
Description: Reads the HTTP response.
Example usage: AT+HTTPREAD

AT+HTTPTERM
Description: Terminates the HTTP connection.
Example usage: AT+HTTPTERM

The examples above are common AT commands used to connect to the internet via the GSM module and send/receive data via HTTP. The full list and detailed descriptions of these commands are contained in the GSM module documentation.