使用EG91EXGA-128-SGNS和TM4C129XNCZAD在各种欧洲M2M场景中实现可靠的4G (LTE)蜂窝网络连接

符合3GPP Release 11标准的LTE Cat.1物联网解决方案

LTE Cat.1 3 Click (for Europe) with Fusion for Tiva v8

已发布 7月 22, 2024

点击板

LTE Cat.1 3 Click (for Europe)

开发板

Fusion for Tiva v8

编译器

NECTO Studio

微控制器单元

TM4C129XNCZAD

使用 LTE Cat 1 标准为欧洲数据传输中的 M2M 应用建立蜂窝网络连接

硬件概览

它是如何工作的？

LTE Cat.1 3 Click（适用于欧洲）基于 Quectel 的 EG91EXGA-128-SGNS 嵌入式 4G 无线通信模块，具有接收分集功能。该模块支持多种无线通信标准，包括 LTE-FDD、WCDMA 和 GSM，提供跨多种网络的可靠数据连接。此模块还提供语音功能（车联网版本支持语音和数据功能），旨在满足客户的特定需求。LTE Cat.1 3 Click 支持多种 LTE 频段（B1/B3/B7/B8/B20/B28）和频段 B1 和 B8 的接收分集。此外，它还支持多星座 GNSS，包括 GPS、GLONASS、北斗/Compass、Galileo 和 QZSS。它完全集成了 TCP、UDP 和 PPP 等互联网服务协议，易于使用扩展 AT 命令。此 Click 板™ 几乎满足 M2M 应用的所有要求，如汽车、智能计量、跟踪系统、安全、路由器、无线 POS 等。EG91EXGA-128-SGNS 与主 MCU 之间的通信通过 UART 接口进行，使用标准的 UART RX 和 TX 引脚以及硬件流控制引脚（CTS/RTS/RI - 清除发送/准备发送/振铃指示器）以实现高效数据传输。模块的默认通信速度为 115200bps，允许通过 AT 命令进行无缝数据交换。值得注意的是，此模块的车联网版本还具有音频接口，可通过 I2C 接口访问。LTE Cat.1 3 Click 音频接口通过 MAX9860 进行操作，MAX9860 是一个可通

过 I2C 接口配置的 16 位单声道音频语音编解码器。此设置与板背面的一个插孔配合使用，设计用于 CTIA 标准耳机，这些耳机通常用于现代智能手机，并具有组合音频和麦克风连接器。该标准确保与各种耳机和耳麦的兼容性。此外，音频接口支持高级功能，如回声消除和噪声抑制，增强语音通信的清晰度和质量。LTE Cat.1 3 Click 还包括一个用于电源和数据传输的 USB Type C 连接器，符合 USB 2.0 规范（仅限从属）。此接口支持高达 480Mbps 的数据传输速率，便于 AT 命令通信、数据传输、GNSS NMEA 语句输出、软件调试、固件升级和通过 USB 进行语音通信。板上带有一个 USB FW 升级开关，标记为 USB BOOT，用于管理固件升级。此开关有 0 和 1 两个位置，0 为正常操作，1 为通过 USB 升级固件，确保简便的升级过程。此外，此 Click 板™ 包含若干增强其实用性和控制的附加功能。PWR 按钮允许用户轻松打开或关闭模块，而 RESET 按钮提供快速重置模块的方式。这些功能还可以通过 mikroBUS™ 引脚 PWR 和 RST 数字控制，提供更大的灵活性。此外，这些控制功能有专用的测试点，便于调试和测试。板上还具有两个视觉指示器，提供实时状态更新。红色的 NET LED 提供网络活动反馈：在搜索网络时慢闪，在数据

传输期间快闪，在语音通话期间保持常亮。黄色的 STAT LED 指示模块的电源状态，当模块关闭时熄灭，当模块通电时亮起。板上还包括 DBG TX/RX 接口测试点，用于调试 UART 通信，简化开发和故障排除过程。板上有三个 u.Fl 连接器，分别用于 GNSS、LTE 和 LTE/WCDMA 接收分集天线，MIKROE 提供 LTE 平板旋转天线和主动 GPS 天线，以及 IPEX-SMA 电缆，以实现灵活高效的连接选项。此外，用户可以轻松选择 GNSS 天线的电源，通过在 GNSS ANT 跳线之间选择 3.3V 和 5V。板上还配有一个微型 SIM 卡插槽，支持 1.8V 和 3.0V uSIM 卡，确保与广泛的蜂窝网络兼容，并允许用户选择最适合其特定使用情况的服务提供商。此 Click 板™ 可以通过 VCC SEL 跳线选择使用 3.3V 或 5V 逻辑电压水平。由于 EG91-EX 模块在 3.8V 下工作，还使用了 TXB0106 和 PCA9306 逻辑电平转换器以确保正常运行和精确的信号电平转换。这样，3.3V 和 5V 的 MCU 都可以正确使用通信线路。此外，该 Click 板™ 配有一个包含易于使用的函数和示例代码的库，可用作进一步开发的参考。

LTE Cat.1 3 Click (for Europe) hardware overview image

功能概述

开发板

Fusion for TIVA v8 是一款专为快速开发嵌入式应用的需求而特别设计的开发板。它支持广泛的微控制器，如不同的32位ARM® Cortex®-M基础MCUs，来自Texas Instruments，无论它们的引脚数量如何，并且具有一系列独特功能，例如首次通过WiFi网络实现的嵌入式调试器/程序员。开发板布局合理，设计周到，使得最终用户可以在一个地方找到所有必要的元素，如开关、按钮、指示灯、连接器等。得益于创新的制造技术，Fusion for TIVA v8 提供了流畅而沉浸式的工作体验，允许在任何情况下、任何地方、任何

时候都能访问。Fusion for TIVA v8开发板的每个部分都包含了使同一板块运行最高效的必要组件。一个先进的集成CODEGRIP程序/调试模块提供许多有价值的编程/调试选项，包括对JTAG、SWD和SWO Trace（单线输出）的支持，并与Mikroe软件环境无缝集成。此外，它还包括一个干净且调节过的开发板电源供应模块。它可以使用广泛的外部电源，包括电池、外部12V电源供应和通过USB Type-C（USB-C）连接器的电源。通信选项如USB-UART、USB HOST/DEVICE、CAN（如果MCU卡支持的话）和以

太网也包括在内。此外，它还拥有广受好评的 mikroBUS™标准，为MCU卡提供了标准化插座（SiBRAIN标准），以及两种显示选项，用于TFT板线产品和基于字符的LCD。Fusion for TIVA v8 是Mikroe快速开发生态系统的一个组成部分。它由Mikroe软件工具原生支持，得益于大量不同的Click板™（超过一千块板），其数量每天都在增长，它涵盖了原型制作和开发的许多方面。

微控制器概述

MCU卡片 / MCU

类型

8th Generation

建筑

ARM Cortex-M4

MCU 内存 (KB)

1024

硅供应商

Texas Instruments

引脚数

212

RAM (字节)

262144

你完善了我！

配件

主动 GPS 天线旨在增强您的 GPS 和 GNSS Click 板™ 的性能。这款外置天线结构坚固，适用于各种天气条件。凭借 1575.42MHz 的频率范围和 50Ohm 的阻抗，它确保了可靠的信号接收。天线在较宽的角度范围内提供大于 -4dBic 的增益，确保超过 75% 的覆盖率。± 5MHz 的带宽进一步保证了精确的数据采集。天线采用右旋圆极化 (RHCP)，提供稳定的信号接收。其紧凑的尺寸为 48.5×39×15mm，配有 2 米长的电缆，安装方便。磁性天线类型与 SMA 公连接器确保了安全便捷的连接。如果您需要为定位设备提供可靠的外置天线，我们的主动 GPS 天线是完美的解决方案。

LTE Cat.1 3 Click (for Europe) accessories 1 image

LTE 平板旋转天线是提升 3G/4G LTE 设备性能的多功能选择。其宽频率范围为 700-2700MHz，确保在全球主要蜂窝频段上的最佳连接性。这款平板天线具有 SMA 公连接器，便于直接连接到您的设备或 SMA 模块连接器。其突出特点之一是可调角度，可按 45⁰ 增量设置（0⁰/45⁰/90⁰），允许您微调天线的方向以获得最佳信号接收。凭借 50Ω 的阻抗和 <2.0:1 的 VSW 比率，这款天线确保了可靠且高效的连接。其 5dB 增益、垂直极化和全向辐射模式增强了信号强度，适用于各种应用。天线尺寸为 196mm 长和 38mm 宽，提供紧凑且有效的连接解决方案。最大输入功率为 50W，能够满足各种设备的需求。

LTE Cat.1 3 Click (for Europe) accessories 2 image

IPEX-SMA 电缆是一种射频（RF）电缆组件。"IPEX" 指的是 IPEX 连接器，这是一种常用于小型电子设备中的微型同轴连接器。"SMA" 代表 SubMiniature Version A，是另一种常用于 RF 应用的同轴连接器。IPEX-SMA 电缆组件在一端具有 IPEX 连接器，另一端具有 SMA 连接器，使其能够连接使用这些特定连接器的设备或组件。这些电缆通常用于 WiFi 或蜂窝天线、GPS 模块以及其他需要可靠且低损耗连接的射频通信系统中的应用。

LTE Cat.1 3 Click (for Europe) accessories 3 image

使用的MCU引脚

mikroBUS™映射器

Module Power-ON

PE3

Reset / ID SEL

PB6

RST

UART RTS / ID COMM

PE7

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

Ring Indicator

PD0

PWM

UART CTS

PB4

INT

UART TX

PA1

UART RX

PA0

I2C Clock

PB2

SCL

I2C Data

PB3

SDA

Power Supply

Ground

GND

“仔细看看！”

Click board™ 原理图

LTE Cat.1 3 Click (for Europe) Schematic schematic

一步一步来

项目组装

Fusion for PIC v8 front image hardware assembly

从选择您的开发板和Click板™开始。以Fusion for Tiva v8作为您的开发板开始

GNSS2 Click front image hardware assembly

SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly

GNSS2 Click complete accessories setup image hardware assembly

v8 SiBRAIN Access MB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

NECTO Output Selection Step Image hardware assembly

实时跟踪您的结果

应用程序输出

1. 应用程序输出 - 在调试模式下，“应用程序输出”窗口支持实时数据监控，直接提供执行结果的可视化。请按照提供的教程正确配置环境，以确保数据正确显示。

2. UART 终端 - 使用UART Terminal通过USB to UART converter监视数据传输，实现Click board™与开发系统之间的直接通信。请根据项目需求配置波特率和其他串行设置，以确保正常运行。有关分步设置说明，请参考提供的教程。

3. Plot 输出 - Plot功能提供了一种强大的方式来可视化实时传感器数据，使趋势分析、调试和多个数据点的对比变得更加直观。要正确设置，请按照提供的教程，其中包含使用Plot功能显示Click board™读数的分步示例。在代码中使用Plot功能时，请使用以下函数：plot(insert_graph_name, variable_name);。这是一个通用格式，用户需要将“insert_graph_name”替换为实际图表名称，并将“variable_name”替换为要显示的参数。

软件支持

库描述

该库包含 LTE Cat.1 3 Click (for Europe) 驱动程序的 API。

Key functions:

ltecat13ex_write_register - 此功能将数据字节写入选定的寄存器地址。
ltecat13ex_max9860_cfg - 此功能用于设置 LTE Cat.1 3 Click 板上 MAX9860 的基本配置。
ltecat13ex_send_sms_pdu - 此功能以 PDU 模式发送短信到手机号码。

开源

代码示例

完整的应用程序代码和一个现成的项目可以通过NECTO Studio包管理器直接安装到NECTO Studio。应用程序代码也可以在MIKROE的GitHub账户中找到。

/*!
 * @file main.c
 * @brief LTE Cat.1 3 EX Click Example.
 *
 * # Description
 * Application example shows device capability of connecting to the network and 
 * sending SMS, TCP/UDP messages, calling the selected number, or getting GNSS location
 * using standard "AT" commands. 
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Sets the device configuration for sending SMS, TCP/UDP messages, calling the selected number
 * or GNSS location.
 *
 * ## Application Task
 * Depending on the selected demo example, it sends an SMS message 
 * (in PDU or TXT mode) or a TCP/UDP message, calls the selected number or
 * gets GNSS location.
 *
 * ## Additional Function
 * - static void ltecat13ex_clear_app_buf ( void )
 * - static void ltecat13ex_log_app_buf ( void )
 * - static err_t ltecat13ex_process ( ltecat13ex_t *ctx )
 * - static void ltecat13ex_error_check( err_t error_flag )
 * - static void ltecat13ex_log_app_buf ( void )
 * - static err_t ltecat13ex_rsp_check ( uint8_t *rsp )
 * - static err_t ltecat13ex_cfg_for_network ( void )
 * - static err_t ltecat13ex_check_connection ( void )
 * - static err_t ltecat13ex_cfg_for_example ( void )
 * - static err_t ltecat13ex_example( void )
 * - static void gnss_parser_application ( char *rsp )
 *
 * @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 Ilic 
 *
 */

#include "board.h"
#include "log.h"
#include "ltecat13ex.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 EXAMPLE_CALL                        2               // Example of calling selected phone number
#define EXAMPLE_GNSS                        3               // Example of getting GNSS location
#define DEMO_EXAMPLE                        EXAMPLE_TCP_UDP // Example selection macro

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

// SMS/CALL example parameters
#define SIM_SMSC                            ""              // Set valid SMS Service Center Address - only in SMS PDU mode
#define PHONE_NUMBER                        ""              // Set Phone number to message or call
#define SMS_MODE                            "0"             // 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                     "LTE Cat.1 3 EX click board - demo example."

// Application buffer size
#define APP_BUFFER_SIZE                     500
#define PROCESS_BUFFER_SIZE                 200

/**
 * @brief Example states.
 * @details Predefined enum values for application example state.
 */
typedef enum
{
    LTECAT13EX_CONFIGURE_FOR_NETWORK = 1,
    LTECAT13EX_WAIT_FOR_CONNECTION,
    LTECAT13EX_CONFIGURE_FOR_EXAMPLE,
    LTECAT13EX_EXAMPLE

} ltecat13ex_example_state_t;

static ltecat13ex_t ltecat13ex;
static log_t logger;

static uint8_t app_buf[ APP_BUFFER_SIZE ] = { 0 };
static uint8_t gnss_info_message[ 200 ] = { 0 };
static int32_t app_buf_len = 0;
static err_t error_flag;
static ltecat13ex_example_state_t example_state;

/**
 * @brief LTE Cat.1 3 EX clearing application buffer.
 * @details This function clears memory of application buffer and reset its length.
 * @note None.
 */
static void ltecat13ex_clear_app_buf ( void );

/**
 * @brief LTE Cat.1 3 EX log application buffer.
 * @details This function logs data from application buffer to USB UART.
 * @note None.
 */
static void ltecat13ex_log_app_buf ( void );

/**
 * @brief LTE Cat.1 3 EX data reading function.
 * @details This function reads data from device and concatenates data to application buffer. 
 * @param[in] ctx : Click context object.
 * See #ltecat13ex_t object definition for detailed explanation.
 * @return @li @c  0 - Read some data.
 *         @li @c -1 - Nothing is read.
 * See #err_t definition for detailed explanation.
 * @note None.
 */
static err_t ltecat13ex_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.
 * @param[in] error_flag  Error flag to check.
 */
static void ltecat13ex_error_check( err_t error_flag );

/**
 * @brief Logs application buffer.
 * @details This function logs data from application buffer.
 */
static void ltecat13ex_log_app_buf ( void );

/**
 * @brief Response check.
 * @details This function checks for response and
 * returns the status of response.
 * @param[in] rsp  Expected 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 ltecat13ex_rsp_check ( uint8_t *rsp );

/**
 * @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 ltecat13ex_cfg_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 ltecat13ex_check_connection ( void );

/**
 * @brief Configure device for example.
 * @details Configure device for the specified example.
 * @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 ltecat13ex_cfg_for_example ( void );

/**
 * @brief Execute example.
 * @details This function executes SMS, TCP/UDP or CALL example depending on the DEMO_EXAMPLE macro.
 * @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 ltecat13ex_example( void );

/**
 * @brief GNSS parser application.
 * @details This function logs GNSS data on the USB UART and stores data in gnss_info_message buffer.
 * @param rsp Response buffer.
 * @note None.
 */
static void gnss_parser_application ( char *rsp ) ;

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    ltecat13ex_cfg_t ltecat13ex_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.
    ltecat13ex_cfg_setup( &ltecat13ex_cfg );
    LTECAT13EX_MAP_MIKROBUS( ltecat13ex_cfg, MIKROBUS_1 );
    if ( UART_ERROR == ltecat13ex_init( &ltecat13ex, &ltecat13ex_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    ltecat13ex_process( );
    ltecat13ex_clear_app_buf( );
    Delay_ms ( 1000 );

    if ( 0 == ltecat13ex_get_ri_pin( &ltecat13ex ) )
    {
        ltecat13ex_start_up( &ltecat13ex );
        error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_RDY );
        ltecat13ex_error_check( error_flag );
    }

    // Restart device
    #define MIN_FUN_DEVICE "0"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CFUN, MIN_FUN_DEVICE );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    ltecat13ex_error_check( error_flag );

    #define FULL_FUN_DEVICE "1"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CFUN, FULL_FUN_DEVICE );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    ltecat13ex_error_check( error_flag );
    
    // Check communication
    ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_AT );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    ltecat13ex_error_check( error_flag );
    
    log_info( &logger, " Application Task " );
    example_state = LTECAT13EX_CONFIGURE_FOR_NETWORK;
}

void application_task ( void ) 
{
    switch ( example_state )
    {
        case LTECAT13EX_CONFIGURE_FOR_NETWORK:
        {
            if ( LTECAT13EX_OK == ltecat13ex_cfg_for_network( ) )
            {
                example_state = LTECAT13EX_WAIT_FOR_CONNECTION;
            }
            break;
        }
        case LTECAT13EX_WAIT_FOR_CONNECTION:
        {
            if ( LTECAT13EX_OK == ltecat13ex_check_connection( ) )
            {
                example_state = LTECAT13EX_CONFIGURE_FOR_EXAMPLE;
            }
            break;
        }
        case LTECAT13EX_CONFIGURE_FOR_EXAMPLE:
        {
            if ( LTECAT13EX_OK == ltecat13ex_cfg_for_example( ) )
            {
                example_state = LTECAT13EX_EXAMPLE;
            }
            break;
        }
        case LTECAT13EX_EXAMPLE:
        {
            ltecat13ex_example( );
            break;
        }
        default:
        {
            log_error( &logger, " Example state." );
            break;
        }
    }
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

static void ltecat13ex_clear_app_buf ( void ) 
{
    memset( app_buf, 0, app_buf_len );
    app_buf_len = 0;
}

static void ltecat13ex_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 ] );
    }
    log_printf( &logger, "============================\r\n" );
}

static err_t ltecat13ex_process ( void ) 
{
    uint8_t rx_buf[ PROCESS_BUFFER_SIZE ] = { 0 };
    int32_t overflow_bytes = 0;
    int32_t rx_cnt = 0;
    int32_t rx_size = ltecat13ex_generic_read( &ltecat13ex, rx_buf, PROCESS_BUFFER_SIZE );
    if ( ( rx_size > 0 ) && ( rx_size <= APP_BUFFER_SIZE ) ) 
    {
        if ( ( app_buf_len + rx_size ) > APP_BUFFER_SIZE ) 
        {
            overflow_bytes = ( app_buf_len + rx_size ) - APP_BUFFER_SIZE;
            app_buf_len = APP_BUFFER_SIZE - rx_size;
            memmove ( app_buf, &app_buf[ overflow_bytes ], app_buf_len );
            memset ( &app_buf[ app_buf_len ], 0, overflow_bytes );
        }
        for ( rx_cnt = 0; rx_cnt < rx_size; rx_cnt++ ) 
        {
            if ( rx_buf[ rx_cnt ] ) 
            {
                app_buf[ app_buf_len++ ] = rx_buf[ rx_cnt ];
            }
        }
        return LTECAT13EX_OK;
    }
    return LTECAT13EX_ERROR;
}

static err_t ltecat13ex_rsp_check ( uint8_t *rsp )
{
    uint32_t timeout_cnt = 0;
    uint32_t timeout = 10000;
    err_t error_flag = ltecat13ex_process( );
    if ( ( LTECAT13EX_OK != error_flag ) && ( LTECAT13EX_ERROR != error_flag ) )
    {
        return error_flag;
    }
    while ( ( 0 == strstr( app_buf, rsp ) ) &&
            ( 0 == strstr( app_buf, LTECAT13EX_RSP_ERROR ) ) )
    {
        error_flag = ltecat13ex_process( );
        if ( ( LTECAT13EX_OK != error_flag ) && ( LTECAT13EX_ERROR != error_flag ) )
        {
            return error_flag;
        }
        if ( timeout_cnt++ > timeout )
        {
            ltecat13ex_clear_app_buf( );
            return LTECAT13EX_ERROR_TIMEOUT;
        }
        Delay_ms ( 1 );
    }
    if ( strstr( app_buf, rsp ) )
    {
        return LTECAT13EX_OK;
    }
    else if ( strstr( app_buf, LTECAT13EX_RSP_ERROR ) )
    {
        return LTECAT13EX_ERROR_CMD;
    }
    else
    {
        return LTECAT13EX_ERROR_UNKNOWN;
    }
}

static void ltecat13ex_error_check( err_t error_flag )
{
    switch ( error_flag )
    {
        case LTECAT13EX_OK:
        {
            ltecat13ex_log_app_buf( );
            break;
        }
        case LTECAT13EX_ERROR:
        {
            log_error( &logger, " Overflow!" );
            break;
        }
        case LTECAT13EX_ERROR_TIMEOUT:
        {
            log_error( &logger, " Timeout!" );
            break;
        }
        case LTECAT13EX_ERROR_CMD:
        {
            ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_QIGETERROR );
            ltecat13ex_log_app_buf( );
            break;
        }
        case LTECAT13EX_ERROR_UNKNOWN:
        default:
        {
            log_error( &logger, " Unknown!" );
            break;
        }
    }
    ltecat13ex_clear_app_buf(  );
    Delay_ms ( 500 );
}

static err_t ltecat13ex_cfg_for_network( void )
{
    err_t func_error = LTECAT13EX_OK;
#if ( ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP ) || ( DEMO_EXAMPLE == EXAMPLE_SMS ) || ( DEMO_EXAMPLE == EXAMPLE_CALL ) || ( DEMO_EXAMPLE == EXAMPLE_GNSS ) )
    // Deregister from network
    #define DEREGISTER_FROM_NETWORK "2"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_COPS, DEREGISTER_FROM_NETWORK );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
    
    // Set SIM APN
    ltecat13ex_set_sim_apn( &ltecat13ex, SIM_APN );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Enable full functionality
    #define FULL_FUNCTIONALITY "1"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CFUN, FULL_FUNCTIONALITY );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Enable network registartion
    #define ENABLE_REG "2"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CREG, ENABLE_REG );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
    
    // Automatic registration
    #define AUTOMATIC_REGISTRATION "0"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_COPS, AUTOMATIC_REGISTRATION );

#endif

    return func_error;
}

static err_t ltecat13ex_check_connection( void )
{
#if ( ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP ) || ( DEMO_EXAMPLE == EXAMPLE_SMS ) || ( DEMO_EXAMPLE == EXAMPLE_CALL ) )
    #define CONNECTED_HOME      "+CREG: 2,1"
    #define CONNECTED_ROAMING   "+CREG: 2,5"
    ltecat13ex_send_cmd_check( &ltecat13ex, LTECAT13EX_CMD_CREG );
    ltecat13ex_process( );
    if ( strstr( app_buf, CONNECTED_HOME ) || strstr( app_buf, CONNECTED_ROAMING ) )
    {
        Delay_ms ( 100 );
        ltecat13ex_process( );
        ltecat13ex_log_app_buf( );
        log_printf( &logger, "\r\n" );
        ltecat13ex_clear_app_buf( );
        // Check signal quality
        ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_CSQ );
        error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
        ltecat13ex_error_check( error_flag );
        return error_flag;
    }
    return LTECAT13EX_ERROR;
    Delay_ms ( 500 );
#endif
    return LTECAT13EX_OK;
}

static err_t ltecat13ex_cfg_for_example ( void )
{
    err_t func_error = LTECAT13EX_OK;
#if ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP )
    #define ACTIVATE_CONTEXT "1"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QIACT, ACTIVATE_CONTEXT );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QICSGP, ACTIVATE_CONTEXT );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

#elif ( DEMO_EXAMPLE == EXAMPLE_SMS )
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CMGF, SMS_MODE );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    #define DEFAULT_ALPHABET    "\"GSM\""
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_CSCS, DEFAULT_ALPHABET );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
#elif ( DEMO_EXAMPLE == EXAMPLE_CALL )
    if ( LTECAT13EX_OK != ltecat13ex_max9860_cfg( &ltecat13ex ) )
    {
        log_error( &logger, " MAX9860 configuration." );
        for ( ; ; );
    }
    
#elif ( DEMO_EXAMPLE == EXAMPLE_GNSS )
    #define TURN_ON_GPS     "1"
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QGPS, TURN_ON_GPS );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

#else
    #error "No demo example selected"
#endif
    return func_error;
}

static err_t ltecat13ex_example ( void )
{
    err_t func_error = LTECAT13EX_OK;
#if ( DEMO_EXAMPLE == EXAMPLE_TCP_UDP )
    uint8_t txt_end[ ] = "\032";
    uint8_t cmd_buf[ 100 ] = { 0 };
    
    #define CONTEXT_ID      "1"
    #define CONNECT_ID_TCP  "1"
    #define SEVICE_TYPE_TCP "\"TCP\""
    #define LOCAL_PORT      "0"
    #define ACCESS_MODE     "0"
    #define MAX_READ_SIZE   "1500"

    // Open TCP socket
    strcpy( cmd_buf, CONTEXT_ID );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, CONNECT_ID_TCP );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, SEVICE_TYPE_TCP );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, REMOTE_IP );
    strcat( cmd_buf, "\"," );
    strcat( cmd_buf, REMOTE_PORT );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, LOCAL_PORT );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, ACCESS_MODE );
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QIOPEN, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Send data to TCP socket
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QISEND, CONNECT_ID_TCP );
    strcpy( cmd_buf, MESSAGE_CONTENT );
    strcat( cmd_buf, txt_end );
    ltecat13ex_rsp_check( ">" );
    ltecat13ex_send_cmd( &ltecat13ex, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_SEND_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Read TCP socket data
    strcpy( cmd_buf, CONNECT_ID_TCP );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, MAX_READ_SIZE );
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QIRD, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Close TCP socket
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QICLOSE, CONNECT_ID_TCP );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

    #define CONNECT_ID_UDP  "2"
    #define SEVICE_TYPE_UDP "\"UDP\""

    // Open UDP socket
    strcpy( cmd_buf, CONTEXT_ID );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, CONNECT_ID_UDP );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, SEVICE_TYPE_UDP );
    strcat( cmd_buf, ",\"" );
    strcat( cmd_buf, REMOTE_IP );
    strcat( cmd_buf, "\"," );
    strcat( cmd_buf, REMOTE_PORT );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, LOCAL_PORT );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, ACCESS_MODE );
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QIOPEN, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Send data to UDP socket
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QISEND, CONNECT_ID_UDP );
    strcpy( cmd_buf, MESSAGE_CONTENT );
    strcat( cmd_buf, txt_end );
    ltecat13ex_rsp_check( ">" );
    ltecat13ex_send_cmd( &ltecat13ex, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_SEND_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Read UDP socket data
    strcpy( cmd_buf, CONNECT_ID_UDP );
    strcat( cmd_buf, "," );
    strcat( cmd_buf, MAX_READ_SIZE );
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QIRD, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );

    // Close UDP socket
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QICLOSE, CONNECT_ID_UDP );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;

    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
#elif ( DEMO_EXAMPLE == EXAMPLE_SMS )

    // Check SMS mode
    #define CMGF_PDU "+CMGF: 0"
    #define CMGF_TXT "+CMGF: 1"
    ltecat13ex_send_cmd_check( &ltecat13ex, LTECAT13EX_CMD_CMGF );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    if ( strstr( app_buf, CMGF_PDU ) )
    {
        ltecat13ex_error_check( error_flag );
        // Send SMS in PDU mode
        ltecat13ex_send_sms_pdu( &ltecat13ex, SIM_SMSC, PHONE_NUMBER, MESSAGE_CONTENT );
        error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
        func_error |= error_flag;
    }
    else if ( strstr( app_buf, CMGF_TXT ) )
    {
        ltecat13ex_error_check( error_flag );
        // Send SMS in TXT mode
        ltecat13ex_send_sms_text ( &ltecat13ex, PHONE_NUMBER, MESSAGE_CONTENT );
        error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
        func_error |= error_flag;
    }
    ltecat13ex_error_check( error_flag );
    // 30 seconds delay
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

#elif ( DEMO_EXAMPLE == EXAMPLE_CALL )
    uint8_t cmd_buf[ 100 ] = { 0 };
    
    strcpy( cmd_buf, LTECAT13EX_CMD_ATD );
    ltecat13ex_clear_app_buf( );
    strcat( cmd_buf, PHONE_NUMBER );
    strcat( cmd_buf, ";" );
    
    log_printf( &logger, " Calling selected number \r\n" );
    ltecat13ex_send_cmd( &ltecat13ex, cmd_buf );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
    
    ltecat13ex_clear_app_buf( );
    log_printf( &logger, "Dialing \r\n" );
    #define CHECK_DIALING "+CLCC: 1,0,2"  
    ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_CLCC );    
    error_flag = ltecat13ex_rsp_check( CHECK_DIALING );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
    
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    #define CHECK_ANSWERED "+CLCC: 1,0,0"  
    ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_CLCC ); 
    error_flag = ltecat13ex_rsp_check( CHECK_ANSWERED );   
    while ( LTECAT13EX_OK != error_flag )
    {
        ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_CLCC ); 
        error_flag = ltecat13ex_rsp_check( CHECK_ANSWERED );    
    }
    log_printf( &logger, "Answered \r\n" );
    ltecat13ex_error_check( error_flag );

    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    
    log_printf( &logger, "Hanging up \r\n" );
    ltecat13ex_send_cmd( &ltecat13ex, LTECAT13EX_CMD_CHUP );
    ltecat13ex_clear_app_buf( );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    ltecat13ex_error_check( error_flag );
    ltecat13ex_clear_app_buf( );
    
    // 10 seconds delay
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

#elif ( DEMO_EXAMPLE == EXAMPLE_GNSS )
    #define GPS_NEMA_GGA    "\"GGA\""
    ltecat13ex_send_cmd_with_params( &ltecat13ex, LTECAT13EX_CMD_QGPSGNMEA, GPS_NEMA_GGA );
    error_flag = ltecat13ex_rsp_check( LTECAT13EX_RSP_OK );
    func_error |= error_flag;
    gnss_parser_application( app_buf );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );

#else
    #error "No demo example selected"
#endif
    return func_error;
}

static void gnss_parser_application ( char *rsp ) 
{
    char element_buf[ 100 ] = { 0 };
    if ( LTECAT13EX_OK == ltecat13ex_parse_gpgga( rsp, LTECAT13EX_GPGGA_LATITUDE, element_buf ) )
    {        
        memset( gnss_info_message, 0, 200 ); 
        if ( strlen( element_buf ) > 0 )
        {
            strcpy( gnss_info_message, "GNSS info\n\r" );
            strcat( gnss_info_message, "Latitude: " );
            strncat( gnss_info_message, element_buf, 2 );
            strcat( gnss_info_message, " deg, " );
            strcat( gnss_info_message, &element_buf[ 2 ] );
            strcat( gnss_info_message, " min" );
            ltecat13ex_parse_gpgga( rsp, LTECAT13EX_GPGGA_LONGITUDE, element_buf );
            strcat( gnss_info_message, "\n\rLongitude: " );
            strncat( gnss_info_message, element_buf, 3 );
            strcat( gnss_info_message, " deg, " );
            strcat( gnss_info_message, &element_buf[ 3 ] );
            strcat( gnss_info_message, " min" );
            memset( element_buf, 0, sizeof( element_buf ) );
            ltecat13ex_parse_gpgga( rsp, LTECAT13EX_GPGGA_ALTITUDE, element_buf );
            strcat( gnss_info_message, "\n\rAltitude: " );
            strcat( gnss_info_message, element_buf );
            strcat( gnss_info_message, " m" );
            log_printf( &logger, "%s\r\n", gnss_info_message );
        }
        else
        {
            log_printf( &logger, " Waiting for the position fix...\r\n" );
        }
        log_printf( &logger, "\r\n-----------------------------------\r\n" );
        ltecat13ex_clear_app_buf();
    }
}

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