Establish a wireless data link to a GSM/GPSR network with SARA-G450 and STM32F091RC

/*!
 * @file main.c
 * @brief GSM 5 Click 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, wakes the module up and tests the communication.
 *
 * ## Application Task
 * Application task is split in few stages:
 *  - GSM5_CONFIGURE_FOR_NETWORK: 
 * Sets configuration to device to be able to connect to the network.
 * 
 *  - GSM5_WAIT_FOR_CONNECTION: 
 * Waits for the network registration indicated via CREG URC event and then checks
 * the connection status.
 * 
 *  - GSM5_CONFIGURE_FOR_EXAMPLE:
 * Sets the device configuration for sending SMS or TCP/UDP messages depending on the 
 * selected demo example.
 * 
 *  - GSM5_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.
 *
 * ## Additional Function
 * - static void gsm5_clear_app_buf ( void )
 * - static err_t gsm5_process ( void )
 * - static void gsm5_error_check( err_t error_flag )
 * - static void gsm5_log_app_buf ( void )
 * - static err_t gsm5_rsp_check ( void )
 * - static err_t gsm5_configure_for_network( void )
 * - static err_t gsm5_check_connection( void )
 * - static err_t gsm5_configure_for_example( void )
 * - static err_t gsm5_example( void )
 *
 * @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"
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "gsm5.h"
#include "generic_pointer.h"
#include "conversions.h"

// Example selection macros
#define EXAMPLE_TCP_UDP                     0               // Example of sending messages to a TCP/UDP echo server
#define EXAMPLE_SMS                         1               // Example of sending SMS to a phone number 
#define DEMO_EXAMPLE                        EXAMPLE_TCP_UDP // Example selection macro

// SIM APN config
#define SIM_APN                             ""              // Set valid SIM APN

// SMS example parameters
#define SIM_SMSC                            ""              // Set valid SMS Service Center Address - only in SMS PDU mode
#define PHONE_NUMBER_TO_MESSAGE             ""              // Set Phone number to message    
#define SMS_MODE                            "1"             // SMS mode: "0" - PDU, "1" - TXT

// TCP/UDP example parameters
#define REMOTE_IP                           "77.46.162.162" // TCP/UDP echo server IP address
#define REMOTE_PORT                         "51111"         // TCP/UDP echo server port

// Message content
#define MESSAGE_CONTENT                     "GSM 5 click board - demo example."

// Application buffer size
#define PROCESS_BUFFER_SIZE                 300

/**
 * @brief Example states.
 * @details Predefined enum values for application example state.
 */
typedef enum
{
    GSM5_CONFIGURE_FOR_NETWORK = 1,
    GSM5_WAIT_FOR_CONNECTION,
    GSM5_CONFIGURE_FOR_EXAMPLE,
    GSM5_EXAMPLE

} gsm5_example_state_t;

static gsm5_t gsm5;
static log_t logger;

/**
 * @brief Application example variables.
 * @details Variables used in application example.
 */
static char app_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
static int32_t app_buf_len = 0;
static int32_t app_buf_cnt = 0;
static err_t error_flag;
static gsm5_example_state_t example_state;

/**
 * @brief Clearing application buffer.
 * @details This function clears memory of application 
 * buffer and reset its length and counter.
 */
static void gsm5_clear_app_buf ( void );

/**
 * @brief Data reading function.
 * @details This function reads data from device and 
 * appends it to the application buffer.
 * @return @li @c  0 - Some data is read.
 *         @li @c -1 - Nothing is read.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_process ( void );

/**
 * @brief Check for errors.
 * @details This function checks for different types of 
 * errors and logs them on UART or logs the response if no errors occured.
 */
static void gsm5_error_check( err_t error_flag );

/**
 * @brief Logs application buffer.
 * @details This function logs data from application buffer.
 */
static void gsm5_log_app_buf ( void );

/**
 * @brief Response check.
 * @details This function checks for response and 
 * returns the status of response.
 * @return @li @c  0 - OK response.
 *         @li @c -2 - Timeout error.
 *         @li @c -3 - Command error.
 *         @li @c -4 - Unknown error.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_rsp_check ( void );

/**
 * @brief Configure device for connection to the network.
 * @details Sends commands to configure and enable 
 * connection to the specified network.
 * @return @li @c  0 - OK response.
 *         @li @c -2 - Timeout error.
 *         @li @c -3 - Command error.
 *         @li @c -4 - Unknown error.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_configure_for_network( void );

/**
 * @brief Wait for connection signal.
 * @details Wait for connection signal from CREG URC.
 * @return @li @c  0 - OK response.
 *         @li @c -2 - Timeout error.
 *         @li @c -3 - Command error.
 *         @li @c -4 - Unknown error.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_check_connection( void );

/**
 * @brief Configure device for sending messages.
 * @details Configure device to send txt mode 
 * messages and SMSC of the SIM card.
 * @return @li @c  0 - OK response.
 *         @li @c -2 - Timeout error.
 *         @li @c -3 - Command error.
 *         @li @c -4 - Unknown error.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_configure_for_example( void );

/**
 * @brief Sending text message.
 * @details This function sends text messages to predefined number.
 * @return @li @c  0 - OK response.
 *         @li @c -2 - Timeout error.
 *         @li @c -3 - Command error.
 *         @li @c -4 - Unknown error.
 * See #err_t definition for detailed explanation.
 */
static err_t gsm5_example( void );

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    gsm5_cfg_t gsm5_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.
    gsm5_cfg_setup( &gsm5_cfg );
    GSM5_MAP_MIKROBUS( gsm5_cfg, MIKROBUS_1 );
    if ( UART_ERROR == gsm5_init( &gsm5, &gsm5_cfg ) ) 
    {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );
        for ( ; ; );
    }
    
    gsm5_module_power_on ( &gsm5 );
    
    gsm5_process( );
    gsm5_clear_app_buf( ); 
    app_buf_len = 0;
    app_buf_cnt = 0;
    
    // Check communication
    gsm5_send_cmd( &gsm5, GSM5_CMD_AT );
    error_flag = gsm5_rsp_check( );
    gsm5_error_check( error_flag );
    
    log_info( &logger, " Application Task " );
    example_state = GSM5_CONFIGURE_FOR_NETWORK;
}

void application_task ( void ) 
{
    switch ( example_state )
    {
        case GSM5_CONFIGURE_FOR_NETWORK:
        {
            if ( GSM5_OK == gsm5_configure_for_network( ) )
            {
                example_state = GSM5_WAIT_FOR_CONNECTION;
            }
            break;
        }
        case GSM5_WAIT_FOR_CONNECTION:
        {
            if ( GSM5_OK == gsm5_check_connection( ) )
            {
                example_state = GSM5_CONFIGURE_FOR_EXAMPLE;
            }
            break;
        }
        case GSM5_CONFIGURE_FOR_EXAMPLE:
        {
            if ( GSM5_OK == gsm5_configure_for_example( ) )
            {
                example_state = GSM5_EXAMPLE;
            }
            break;
        }
        case GSM5_EXAMPLE:
        {
            gsm5_example( );
            break;
        }
        default:
        {
            log_error( &logger, " Example state." );
            break;
        }
    }
}

void main ( void ) 
{
    application_init( );

    for ( ; ; ) 
    {
        application_task( );
    }
}

static void gsm5_clear_app_buf ( void ) 
{
    memset( app_buf, 0, app_buf_len );
    app_buf_len = 0;
    app_buf_cnt = 0;
}

static err_t gsm5_process ( void ) 
{
    int32_t rx_size;
    char rx_buff[ PROCESS_BUFFER_SIZE ] = { 0 };
    rx_size = gsm5_generic_read( &gsm5, rx_buff, PROCESS_BUFFER_SIZE );
    if ( rx_size > 0 ) 
    {
        int32_t buf_cnt = 0;
        if ( ( app_buf_len + rx_size ) > PROCESS_BUFFER_SIZE )
        {
            gsm5_clear_app_buf(  );
            return GSM5_ERROR;
        } 
        else 
        {
            buf_cnt = app_buf_len;
            app_buf_len += rx_size;
        }
        for ( int32_t rx_cnt = 0; rx_cnt < rx_size; rx_cnt++ ) 
        {
            if ( rx_buff[ rx_cnt ] != 0 ) 
            {
                app_buf[ ( buf_cnt + rx_cnt ) ] = rx_buff[ rx_cnt ];
            }
            else
            {
                app_buf_len--;
                buf_cnt--;
            }
        }
        return GSM5_OK;
    }
    return GSM5_ERROR;
}

static err_t gsm5_rsp_check ( void )
{
    uint32_t timeout_cnt = 0;
    uint32_t timeout = 120000;
    err_t error_flag = gsm5_process( );
    if ( ( GSM5_OK != error_flag ) && ( GSM5_ERROR != error_flag ) )
    {
        return error_flag;
    }
    while ( ( 0 == strstr( app_buf, GSM5_RSP_OK ) ) && 
            ( 0 == strstr( app_buf, GSM5_RSP_ERROR ) ) )
    {
        error_flag = gsm5_process( );
        if ( ( GSM5_OK != error_flag ) && ( GSM5_ERROR != error_flag ) )
        {
            return error_flag;
        }
        if ( timeout_cnt++ > timeout )
        {
            gsm5_clear_app_buf( );
            return GSM5_ERROR_TIMEOUT;
        }
        Delay_ms( 1 );
    }
    if ( strstr( app_buf, GSM5_RSP_OK ) )
    {
        return GSM5_OK;
    }
    else if ( strstr( app_buf, GSM5_RSP_ERROR ) )
    {
        return GSM5_ERROR_CMD;
    }
    else
    {
        return GSM5_ERROR_UNKNOWN;
    }
}

static void gsm5_error_check( err_t error_flag )
{
    switch ( error_flag )
    {
        case GSM5_OK:
        {
            gsm5_log_app_buf( );
            break;
        }
        case GSM5_ERROR:
        {
            log_error( &logger, " Overflow!" );
            break;
        }
        case GSM5_ERROR_TIMEOUT:
        {
            log_error( &logger, " Timeout!" );
            break;
        }
        case GSM5_ERROR_CMD:
        {
            log_error( &logger, " CMD!" );
            break;
        }
        case GSM5_ERROR_UNKNOWN:
        default:
        {
            log_error( &logger, " Unknown!" );
            break;
        }
    }
    gsm5_clear_app_buf(  );
    Delay_ms( 500 );
}

static void gsm5_log_app_buf ( void )
{
    for ( int32_t buf_cnt = 0; buf_cnt < app_buf_len; buf_cnt++ )
    {
        log_printf( &logger, "%c", app_buf[ buf_cnt ] );
    }
}

static err_t gsm5_configure_for_network( void )
{
    err_t func_error = GSM5_OK;
    // Enable full functionality
    #define FULL_FUNCTIONALITY "1"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_CFUN, FULL_FUNCTIONALITY );
    error_flag = gsm5_rsp_check();
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Set SIM APN
    gsm5_set_sim_apn( &gsm5, SIM_APN );
    error_flag = gsm5_rsp_check();
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Enable network registartion
    #define ENABLE_REG "2"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_CREG, ENABLE_REG );
    error_flag = gsm5_rsp_check();
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    return func_error;
}

static err_t gsm5_check_connection( void )
{
    #define CONNECTED "+CREG: 1"
    gsm5_process( );
    if ( strstr( app_buf, CONNECTED ) )
    {
        Delay_ms( 100 );
        gsm5_process( );
        gsm5_log_app_buf( );
        log_printf( &logger, "\r\n" );
        gsm5_clear_app_buf( );
        // Check signal quality
        gsm5_send_cmd( &gsm5, GSM5_CMD_CSQ );
        error_flag = gsm5_rsp_check( );
        gsm5_error_check( error_flag );
        return error_flag;
    }
    return GSM5_ERROR;
}

static err_t gsm5_configure_for_example( void )
{
    err_t func_error = GSM5_OK;
#if ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP )
    #define ACTIVATE_PDP_CONTEXT "1,1"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_CGACT, ACTIVATE_PDP_CONTEXT );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    #define ACTIVATE_PDP_PROFILE "0,3"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_UPSDA, ACTIVATE_PDP_PROFILE );
    Delay_ms ( 1000 );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
#elif ( DEMO_EXAMPLE == EXAMPLE_SMS )
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_CMGF, SMS_MODE );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
#else
    #error "No demo example selected"
#endif
    return func_error;
}

static err_t gsm5_example( void )
{
    err_t func_error = GSM5_OK;
#if ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP )
    char cmd_buf[ 100 ] = { 0 };
    char urc_buf[ 20 ] = { 0 };
    uint16_t timeout_cnt = 0;
    uint16_t timeout = 30000;
    uint8_t * __generic_ptr socket_num_buf = 0;
    uint8_t tcp_socket_num[ 2 ] = { 0 }; 
    uint8_t udp_socket_num[ 2 ] = { 0 }; 
    
    // Create TCP socket
    #define RSP_USOCR "+USOCR: "
    #define TCP_PROTOCOL "6"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCR, TCP_PROTOCOL );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    socket_num_buf = strstr( app_buf, RSP_USOCR ) + strlen ( RSP_USOCR );
    tcp_socket_num[ 0 ] = *socket_num_buf;
    gsm5_error_check( error_flag );
    
    // Create UDP socket
    #define UDP_PROTOCOL "17"
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCR, UDP_PROTOCOL );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    socket_num_buf = strstr( app_buf, RSP_USOCR ) + strlen ( RSP_USOCR );
    udp_socket_num[ 0 ] = *socket_num_buf;
    gsm5_error_check( error_flag );
    
    // Connect TCP socket to remote IP and port
    strcpy( cmd_buf, tcp_socket_num );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, REMOTE_IP );
    strcat( cmd_buf, "\"," );
    strcat( cmd_buf, REMOTE_PORT );
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCO, cmd_buf );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Connect UDP socket to remote IP and port
    strcpy( cmd_buf, udp_socket_num );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, REMOTE_IP );
    strcat( cmd_buf, "\"," );
    strcat( cmd_buf, REMOTE_PORT );
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCO, cmd_buf );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );

    // Get message length
    uint8_t message_len_buf[ 5 ] = { 0 };
    uint16_t message_len = strlen( MESSAGE_CONTENT );
    uint16_to_str( message_len, message_len_buf );
    l_trim( message_len_buf );
    r_trim( message_len_buf );
    
    // Write message to TCP socket
    strcpy( cmd_buf, tcp_socket_num );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, message_len_buf );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, MESSAGE_CONTENT );
    strcat( cmd_buf, "\"" );
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOWR, cmd_buf );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Read response message from TCP socket
    #define URC_READ_SOCKET_DATA "+UUSORD: "
    strcpy( urc_buf, URC_READ_SOCKET_DATA );
    strcat( urc_buf, tcp_socket_num );
    for ( ; ; )
    {
        gsm5_process( );
        uint8_t * __generic_ptr start_response_buf = strstr( app_buf, urc_buf );
        if ( start_response_buf )
        {
            Delay_ms( 100 );
            gsm5_process( ); 
            uint8_t response_len_buf[ 5 ] = { 0 };
            char * __generic_ptr start_response_len = strstr( start_response_buf, "," ) + 1;
            memcpy ( response_len_buf, start_response_len, app_buf_len - ( start_response_len - app_buf ) );
            strcpy( cmd_buf, tcp_socket_num );
            strcat( cmd_buf, "," );
            strcat( cmd_buf, response_len_buf );
            gsm5_log_app_buf( );
            gsm5_clear_app_buf( );
            gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USORD, cmd_buf );
            error_flag = gsm5_rsp_check( );
            func_error |= error_flag;
            gsm5_error_check( error_flag );
            break;
        }
        if ( timeout_cnt++ > timeout )
        {
            break;
        }
        Delay_ms( 1 );
    }
    timeout_cnt = 0;
    
    // Write message to UDP socket
    strcpy( cmd_buf, udp_socket_num );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, message_len_buf );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, MESSAGE_CONTENT );
    strcat( cmd_buf, "\"" );
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOWR, cmd_buf );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Read response message from UDP socket
    strcpy( urc_buf, URC_READ_SOCKET_DATA );
    strcat( urc_buf, udp_socket_num );
    for ( ; ; )
    {
        gsm5_process( );
        uint8_t * __generic_ptr start_response_buf = strstr( app_buf, urc_buf );
        if ( start_response_buf )
        {
            Delay_ms( 100 );
            gsm5_process( );
            uint8_t response_len_buf[ 5 ] = { 0 };
            char * __generic_ptr start_response_len = strstr( start_response_buf, "," ) + 1;
            memcpy ( response_len_buf, start_response_len, app_buf_len - ( start_response_len - app_buf ) );
            strcpy( cmd_buf, udp_socket_num );
            strcat( cmd_buf, "," );
            strcat( cmd_buf, response_len_buf );
            gsm5_log_app_buf( );
            gsm5_clear_app_buf( );
            gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USORF, cmd_buf );
            error_flag = gsm5_rsp_check( );
            func_error |= error_flag;
            gsm5_error_check( error_flag );
            break;
        }
        if ( timeout_cnt++ > timeout )
        {
            break;
        }
        Delay_ms( 1 );
    }
    
    // Close TCP socket
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCL, tcp_socket_num );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    
    // Close UDP socket
    gsm5_send_cmd_with_parameter( &gsm5, GSM5_CMD_USOCL, udp_socket_num );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    gsm5_error_check( error_flag );
    Delay_ms( 5000 );
#elif ( DEMO_EXAMPLE == EXAMPLE_SMS )
    // Check SMS mode
    #define CMGF_PDU "+CMGF: 0"
    #define CMGF_TXT "+CMGF: 1"
    gsm5_send_cmd_check( &gsm5, GSM5_CMD_CMGF );
    error_flag = gsm5_rsp_check( );
    func_error |= error_flag;
    if ( strstr( app_buf, CMGF_PDU ) )
    {
        gsm5_error_check( error_flag );
        // Send SMS in PDU mode
        gsm5_send_sms_pdu( &gsm5, SIM_SMSC, PHONE_NUMBER_TO_MESSAGE, MESSAGE_CONTENT );
        error_flag = gsm5_rsp_check( );
        func_error |= error_flag;
    }
    else if ( strstr( app_buf, CMGF_TXT ) )
    {
        gsm5_error_check( error_flag );
        // Send SMS in TXT mode
        gsm5_send_sms_text ( &gsm5, PHONE_NUMBER_TO_MESSAGE, MESSAGE_CONTENT );
        error_flag = gsm5_rsp_check( );
        func_error |= error_flag;
    }
    gsm5_error_check( error_flag );
    Delay_ms( 10000 );
    Delay_ms( 10000 );
    Delay_ms( 10000 );
#else
    #error "No demo example selected"
#endif
    return func_error;
}

// ------------------------------------------------------------------------ END