GSM 4 Click

GSM 4 Click is a compact quad-band GSM cellular network communication solution, featuring the quad-band 2.5G GSM/GPRS SARA-G350 module. This module features a full set of options for the cellular networking and communication, such as the network status indication, jamming detection, embedded internet protocols, including TCP/IP, UDP, FTP, PPP, HTTP, SMTP, full GPRS multislot class 10 implementation, and more. Data communication speed is rated up to 42.8 for the uplink and 85.6 kbps for downlink connection.

Click Product page

Click library

• Author : Stefan Filipovic
• Date : May 2023.
• Type : UART type

Software Support

We provide a library for the GSM4 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for GSM4 Click driver.

Standard key functions :

• gsm4_cfg_setup Config Object Initialization function.

  void gsm4_cfg_setup ( gsm4_cfg_t *cfg );

• gsm4_init Initialization function.

  err_t gsm4_init ( gsm4_t *ctx, gsm4_cfg_t *cfg );

Example key functions :

• gsm4_set_sim_apn This function sets APN for sim card.

  void gsm4_set_sim_apn ( gsm4_t *ctx, uint8_t *sim_apn );

• gsm4_send_sms_text This function sends text message to a phone number.

  void gsm4_send_sms_text ( gsm4_t *ctx, uint8_t *phone_number, uint8_t *sms_text );

• gsm4_send_sms_pdu This function sends text message to a phone number in PDU mode.

  err_t gsm4_send_sms_pdu ( gsm4_t *ctx, uint8_t *service_center_number, uint8_t *phone_number, uint8_t *sms_text );

Example Description

Application example shows device capability of connecting to the network and sending SMS or TCP/UDP messages using standard "AT" commands.

The demo application is composed of two sections :

Application Init

Initializes the driver, tests the communication by sending "AT" command, and after that restarts the device.

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    gsm4_cfg_t gsm4_cfg;  /**< Click config object. */

    /**
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX
     * are defined as HAL_PIN_NC, you will
     * need to define them manually for log to work.
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    gsm4_cfg_setup( &gsm4_cfg );
    GSM4_MAP_MIKROBUS( gsm4_cfg, MIKROBUS_1 );
    if ( UART_ERROR == gsm4_init( &gsm4, &gsm4_cfg ) )
    {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );
        for ( ; ; );
    }

    gsm4_process( );
    gsm4_clear_app_buf( );

    // Check communication
    gsm4_send_cmd( &gsm4, GSM4_CMD_AT );
    error_flag = gsm4_rsp_check( GSM4_RSP_OK );
    gsm4_error_check( error_flag );

    // Restart device
    #define RESTART_DEVICE "1,1"
    gsm4_send_cmd_with_par( &gsm4, GSM4_CMD_CFUN, RESTART_DEVICE );
    error_flag = gsm4_rsp_check( GSM4_RSP_OK );
    gsm4_error_check( error_flag );

    log_info( &logger, " Application Task " );
    example_state = GSM4_CONFIGURE_FOR_NETWORK;
}

Application Task

Application task is split in few stages:

• GSM4_CONFIGURE_FOR_NETWORK: Sets configuration to device to be able to connect to the network.
• GSM4_WAIT_FOR_CONNECTION: Waits for the network registration indicated via CREG URC event and then checks the connection status.
• GSM4_CONFIGURE_FOR_EXAMPLE: Sets the device configuration for sending SMS or TCP/UDP messages depending on the selected demo example.
• GSM4_EXAMPLE: Depending on the selected demo example, it sends an SMS message (in PDU or TXT mode) or TCP/UDP message. By default, the TCP/UDP example is selected.

void application_task ( void ) 
{
    switch ( example_state )
    {
        case GSM4_CONFIGURE_FOR_NETWORK:
        {
            if ( GSM4_OK == gsm4_configure_for_network( ) )
            {
                example_state = GSM4_WAIT_FOR_CONNECTION;
            }
            break;
        }
        case GSM4_WAIT_FOR_CONNECTION:
        {
            if ( GSM4_OK == gsm4_check_connection( ) )
            {
                example_state = GSM4_CONFIGURE_FOR_EXAMPLE;
            }
            break;
        }
        case GSM4_CONFIGURE_FOR_EXAMPLE:
        {
            if ( GSM4_OK == gsm4_configure_for_example( ) )
            {
                example_state = GSM4_EXAMPLE;
            }
            break;
        }
        case GSM4_EXAMPLE:
        {
            gsm4_example( );
            break;
        }
        default:
        {
            log_error( &logger, " Example state." );
            break;
        }
    }
}

Note

In order for the examples to work, user needs to set the APN and SMSC (SMS PDU mode only) of entered SIM card as well as the phone number (SMS mode only) to which he wants to send an SMS. Enter valid values for the following macros: SIM_APN, SIM_SMSC and PHONE_NUMBER_TO_MESSAGE.

Example:

• SIM_APN "internet"
• SIM_SMSC "+381610401"
• PHONE_NUMBER_TO_MESSAGE "+381659999999"

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.GSM4

Additional notes and informations

Depending on the development board you are using, you may need USB UART Click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.