RE: Getting error code =4 in ble_stack_init.

kishor babu — Tue, 09 Apr 2019 11:56:28 GMT
Hi Jorgen,
I made " NRF_SDH_BLE_VS_UUID_COUNT =1". Now the system is not resetting and it is able to scan and advertise at a time.
I am able to connect to the central and peripheral at a time, But the issue I am facing is when I am trying to send the data over BLE using nrfconnect the data is printing two times in UART terminal.
/**
 * Copyright (c) 2014 - 2017, Nordic Semiconductor ASA
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
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 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
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 * 
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 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 * 
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 *    Nordic Semiconductor ASA integrated circuit.
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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 */
/**
 * @brief BLE Heart Rate and Running speed Relay application main file.
 *
 * @detail This application demonstrates a simple "Relay".
 * Meaning we pass on the values that we receive. By combining a collector part on
 * one end and a sensor part on the other, we show that the s130 can function
 * simultaneously as a central and a peripheral device.
 *
 * In the figure below, the sensor ble_app_hrs connects and interacts with the relay
 * in the same manner it would connect to a heart rate collector. In this case, the Relay
 * application acts as a central.
 *
 * On the other side, a collector (such as Master Control panel or ble_app_hrs_c) connects
 * and interacts with the relay the same manner it would connect to a heart rate sensor peripheral.
 *
 * Led layout:
 * LED 1: Central side is scanning       LED 2: Central side is connected to a peripheral
 * LED 3: Peripheral side is advertising LED 4: Peripheral side is connected to a central
 *
 * @note While testing, be careful that the Sensor and Collector are actually connecting to the Relay,
 *       and not directly to each other!
 *
 *    Peripheral                  Relay                    Central
 *    +--------+        +-----------|----------+        +-----------+
 *    | Heart  |        | Heart     |   Heart  |        |           |
 *    | Rate   | -----> | Rate     -|-> Rate   | -----> | Collector |
 *    | Sensor |        | Collector |   Sensor |        |           |
 *    +--------+        +-----------|   and    |        +-----------+
 *                      | Running   |   Running|
 *    +--------+        | Speed    -|-> Speed  |
 *    | Running|------> | Collector |   Sensor |
 *    | Speed  |        +-----------|----------+
 *    | Sensor |
 *    +--------+
 */

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf_sdh.h"
#include "nrf_sdh_soc.h"
#include "nrf_sdh_ble.h"
#include "peer_manager.h"
#include "app_timer.h"
#include "bsp_btn_ble.h"
#include "ble.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "ble_db_discovery.h"
#include "ble_hrs.h"
#include "ble_rscs.h"
#include "ble_hrs_c.h"
#include "ble_rscs_c.h"
#include "ble_conn_state.h"
#include "nrf_fstorage.h"
#include "fds.h"
#include "nrf_ble_gatt.h"

#include "ble_nus.h"//added
#include "app_uart.h"//added
#include "app_util_platform.h"//added
#include "ble_nus_c.h"//added
#include "nrf_delay.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"


#define NUS_SERVICE_UUID_TYPE           BLE_UUID_TYPE_VENDOR_BEGIN                  /**< UUID type for the Nordic UART Service (vendor specific). */
#define ECHOBACK_BLE_UART_DATA  0                                       /**< Echo the UART data that is received over the Nordic UART Service back to the sender. */
#define PERIPHERAL_ADVERTISING_LED      BSP_BOARD_LED_2
#define PERIPHERAL_CONNECTED_LED        BSP_BOARD_LED_3
#define CENTRAL_SCANNING_LED            BSP_BOARD_LED_0
#define CENTRAL_CONNECTED_LED           BSP_BOARD_LED_1

#define DEVICE_NAME                     "Relay"                                     /**< Name of device used for advertising. */
#define MANUFACTURER_NAME               "NordicSemiconductor"                       /**< Manufacturer. Will be passed to Device Information Service. */
#define APP_ADV_INTERVAL                300                                         /**< The advertising interval (in units of 0.625 ms). This value corresponds to 187.5 ms. */
#define APP_ADV_TIMEOUT_IN_SECONDS      180                                         /**< The advertising timeout in units of seconds. */

#define APP_BLE_CONN_CFG_TAG            1                                           /**< A tag identifying the SoftDevice BLE configuration. */

#define FIRST_CONN_PARAMS_UPDATE_DELAY  APP_TIMER_TICKS(5000)                       /**< Time from initiating event (connect or start of notification) to first time sd_ble_gap_conn_param_update is called (5 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY   APP_TIMER_TICKS(30000)                      /**< Time between each call to sd_ble_gap_conn_param_update after the first call (30 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT    3                                           /**< Number of attempts before giving up the connection parameter negotiation. */

#define APP_FEATURE_NOT_SUPPORTED       BLE_GATT_STATUS_ATTERR_APP_BEGIN + 2        /**< Reply when unsupported features are requested. */

#define SEC_PARAM_BOND                  1                                           /**< Perform bonding. */
#define SEC_PARAM_MITM                  0                                           /**< Man In The Middle protection not required. */
#define SEC_PARAM_LESC                  0                                           /**< LE Secure Connections not enabled. */
#define SEC_PARAM_KEYPRESS              0                                           /**< Keypress notifications not enabled. */
#define SEC_PARAM_IO_CAPABILITIES       BLE_GAP_IO_CAPS_NONE                        /**< No I/O capabilities. */
#define SEC_PARAM_OOB                   0                                           /**< Out Of Band data not available. */
#define SEC_PARAM_MIN_KEY_SIZE          7                                           /**< Minimum encryption key size in octets. */
#define SEC_PARAM_MAX_KEY_SIZE          16                                          /**< Maximum encryption key size in octets. */

#define SCAN_INTERVAL                   0x00A0                                      /**< Determines scan interval in units of 0.625 millisecond. */
#define SCAN_WINDOW                     0x0050                                      /**< Determines scan window in units of 0.625 millisecond. */
#define SCAN_TIMEOUT                    0

#define MIN_CONNECTION_INTERVAL         (uint16_t) MSEC_TO_UNITS(7.5, UNIT_1_25_MS) /**< Determines minimum connection interval in milliseconds. */
#define MAX_CONNECTION_INTERVAL         (uint16_t) MSEC_TO_UNITS(30, UNIT_1_25_MS)  /**< Determines maximum connection interval in milliseconds. */
#define SLAVE_LATENCY                   0                                           /**< Determines slave latency in terms of connection events. */
#define SUPERVISION_TIMEOUT             (uint16_t) MSEC_TO_UNITS(4000, UNIT_10_MS)  /**< Determines supervision time-out in units of 10 milliseconds. */

#define UUID16_SIZE                     2                                           /**< Size of a UUID, in bytes. */
#define UUID32_SIZE                 4                               /**< Size of 32 bit UUID */
#define UUID128_SIZE                16                              /**< Size of 128 bit UUID */
#define UART_TX_BUF_SIZE        256                                     /**< UART TX buffer size. */
#define UART_RX_BUF_SIZE        256                                     /**< UART RX buffer size. */

#define CENTRAL_LINK_COUNT          1                                             /**< Number of central links used by the application. When changing this number remember to adjust the RAM settings*/
#define PERIPHERAL_LINK_COUNT       1                                             /**< Number of peripheral links used by the application. When changing this number remember to adjust the RAM settings*/


/**@brief   Priority of the application BLE event handler.
 * @note    You shouldn't need to modify this value.
 */
#define APP_BLE_OBSERVER_PRIO           1

/**@brief Macro to unpack 16bit unsigned UUID from an octet stream.
 */
#define UUID16_EXTRACT(DST, SRC) \
    do                           \
    {                            \
        (*(DST))   = (SRC)[1];   \
        (*(DST)) <<= 8;          \
        (*(DST))  |= (SRC)[0];   \
    } while (0)


/**@brief Variable length data encapsulation in terms of length and pointer to data. */
typedef struct
{
    uint8_t  * p_data;   /**< Pointer to data. */
    uint16_t   data_len; /**< Length of data. */
} data_t;


//BLE_HRS_DEF(m_hrs);                                                 /**< Heart rate service instance. */
//BLE_RSCS_DEF(m_rscs);                                               /**< Running speed and cadence service instance. */
//BLE_HRS_C_DEF(m_hrs_c);                                             /**< Heart rate service client instance. */
//BLE_RSCS_C_DEF(m_rscs_c);                                           /**< Running speed and cadence service client instance. */

BLE_NUS_DEF(m_nus);                                                 /**< Heart rate service instance. */
BLE_NUS_C_DEF(m_ble_nus_c);                                             /**< BLE NUS service client instance. */                                              /**< Running speed and cadence service instance. */

NRF_BLE_GATT_DEF(m_gatt);                                           /**< GATT module instance. */
BLE_ADVERTISING_DEF(m_advertising);                                 /**< Advertising module instance. */
BLE_DB_DISCOVERY_DEF(m_db_discovery);                               /**< Database discovery module instances. */


static char cmd[40];//added
bool peripheral_status=0,central_status=0;
bool peripheral_event=0;

static uint16_t m_conn_handle_nus_c  = BLE_CONN_HANDLE_INVALID;     /**< Connection handle for the HRS central application */
//static uint16_t m_conn_handle_rscs_c = BLE_CONN_HANDLE_INVALID;     /**< Connection handle for the RSC central application */
static uint16_t   m_conn_handle          = BLE_CONN_HANDLE_INVALID;                 /**< Handle of the current connection. */
static uint16_t m_conn_handle_to_disc = BLE_CONN_HANDLE_INVALID;    /**< The connection handle on which to retry the DB discovery. */
static bool     m_retry_db_disc;                                    /**< Retry DB discovery if attempted while busy. */
static bool     m_do_retry_db_disc;
static uint16_t   m_ble_nus_max_data_len = BLE_GATT_ATT_MTU_DEFAULT - 3;            /**< Maximum length of data (in bytes) that can be transmitted to the peer by the Nordic UART service module. */
static ble_uuid_t m_adv_uuids[]          =                                          /**< Universally unique service identifier. */
{
    {BLE_UUID_NUS_SERVICE, NUS_SERVICE_UUID_TYPE}
};
/**@brief names which the central applications will scan for, and which will be advertised by the peripherals.
 *  if these are set to empty strings, the UUIDs defined below will be used
 */
static char const m_target_periph_name[] = "";

///**@brief UUIDs which the central applications will scan for if the name above is set to an empty string,
// * and which will be advertised by the peripherals.
// */
//static ble_uuid_t m_adv_uuids[] =
//{
//    {BLE_UUID_HEART_RATE_SERVICE,        BLE_UUID_TYPE_BLE},
//    {BLE_UUID_RUNNING_SPEED_AND_CADENCE, BLE_UUID_TYPE_BLE}
//};

/**@brief Parameters used when scanning. */
static ble_gap_scan_params_t const m_scan_params =
{
    .active   = 1,
    .interval = SCAN_INTERVAL,
    .window   = SCAN_WINDOW,
    .timeout  = SCAN_TIMEOUT,
    #if (NRF_SD_BLE_API_VERSION <= 2)
        .selective   = 0,
        .p_whitelist = NULL,
    #endif
    #if (NRF_SD_BLE_API_VERSION >= 3)
        .use_whitelist = 0,
    #endif
};


/**@brief NUS uuid. */
static ble_uuid_t const m_nus_uuid =
{
    .uuid = BLE_UUID_NUS_SERVICE,
    .type = NUS_SERVICE_UUID_TYPE
};

/**@brief Connection parameters requested for connection. */
static ble_gap_conn_params_t const m_connection_param =
{
    MIN_CONNECTION_INTERVAL,
    MAX_CONNECTION_INTERVAL,
    SLAVE_LATENCY,
    SUPERVISION_TIMEOUT
};


/**@brief Function to handle asserts in the SoftDevice.
 *
 * @details This function will be called in case of an assert in the SoftDevice.
 *
 * @warning This handler is an example only and does not fit a final product. You need to analyze
 *          how your product is supposed to react in case of Assert.
 * @warning On assert from the SoftDevice, the system can only recover on reset.
 *
 * @param[in] line_num     Line number of the failing ASSERT call.
 * @param[in] p_file_name  File name of the failing ASSERT call.
 */
void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
{
    app_error_handler(0xDEADBEEF, line_num, p_file_name);
}

/**@brief Function for handling errors from the Connection Parameters module.
 *
 * @param[in] nrf_error  Error code containing information about what went wrong.
 */
static void conn_params_error_handler(uint32_t nrf_error)
{
    APP_ERROR_HANDLER(nrf_error);
}


/**@brief Parses advertisement data, providing length and location of the field in case
 *        matching data is found.
 *
 * @param[in]  Type of data to be looked for in advertisement data.
 * @param[in]  Advertisement report length and pointer to report.
 * @param[out] If data type requested is found in the data report, type data length and
 *             pointer to data will be populated here.
 *
 * @retval NRF_SUCCESS if the data type is found in the report.
 * @retval NRF_ERROR_NOT_FOUND if the data type could not be found.
 */
static uint32_t adv_report_parse(uint8_t type, data_t * p_advdata, data_t * p_typedata)
{
    uint32_t   index = 0;
    uint8_t  * p_data;

    p_data = p_advdata->p_data;

    while (index < p_advdata->data_len)
    {
        uint8_t field_length = p_data[index];
        uint8_t field_type   = p_data[index + 1];

        if (field_type == type)
        {
            p_typedata->p_data   = &p_data[index + 2];
            p_typedata->data_len = field_length - 1;
            return NRF_SUCCESS;
        }
        index += field_length + 1;
    }
    return NRF_ERROR_NOT_FOUND;
}


/**@brief Function for initiating scanning.
 */
static void scan_start(void)
{
    ret_code_t err_code;

    (void) sd_ble_gap_scan_stop();

    err_code = sd_ble_gap_scan_start(&m_scan_params);
    // It is okay to ignore this error since we are stopping the scan anyway.
    if (err_code != NRF_ERROR_INVALID_STATE)
    {
        APP_ERROR_CHECK(err_code);
    }
}


/**@brief Function for initiating advertising and scanning.
 */
static void adv_scan_start(void)
{
    ret_code_t err_code;

    //check if there are no flash operations in progress
    if (!nrf_fstorage_is_busy(NULL))
    {
        // Start scanning for peripherals and initiate connection to devices which
        // advertise Heart Rate or Running speed and cadence UUIDs.
        scan_start();

        // Turn on the LED to signal scanning.
        bsp_board_led_on(CENTRAL_SCANNING_LED);

        // Start advertising.
        err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
        APP_ERROR_CHECK(err_code);
    }
}


/**@brief Function for handling Peer Manager events.
 *
 * @param[in] p_evt  Peer Manager event.
 */
static void pm_evt_handler(pm_evt_t const * p_evt)
{
    ret_code_t err_code;

    switch (p_evt->evt_id)
    {
        case PM_EVT_BONDED_PEER_CONNECTED:
        {
            NRF_LOG_INFO("Connected to a previously bonded device.");
        } break;

        case PM_EVT_CONN_SEC_SUCCEEDED:
        {
            NRF_LOG_INFO("Connection secured: role: %d, conn_handle: 0x%x, procedure: %d.",
                         ble_conn_state_role(p_evt->conn_handle),
                         p_evt->conn_handle,
                         p_evt->params.conn_sec_succeeded.procedure);
        } break;

        case PM_EVT_CONN_SEC_FAILED:
        {
            /* Often, when securing fails, it shouldn't be restarted, for security reasons.
             * Other times, it can be restarted directly.
             * Sometimes it can be restarted, but only after changing some Security Parameters.
             * Sometimes, it cannot be restarted until the link is disconnected and reconnected.
             * Sometimes it is impossible, to secure the link, or the peer device does not support it.
             * How to handle this error is highly application dependent. */
        } break;

        case PM_EVT_CONN_SEC_CONFIG_REQ:
        {
            // Reject pairing request from an already bonded peer.
            pm_conn_sec_config_t conn_sec_config = {.allow_repairing = false};
            pm_conn_sec_config_reply(p_evt->conn_handle, &conn_sec_config);
        } break;

        case PM_EVT_STORAGE_FULL:
        {
            // Run garbage collection on the flash.
            err_code = fds_gc();
            if (err_code == FDS_ERR_BUSY || err_code == FDS_ERR_NO_SPACE_IN_QUEUES)
            {
                // Retry.
            }
            else
            {
                APP_ERROR_CHECK(err_code);
            }
        } break;

        case PM_EVT_PEERS_DELETE_SUCCEEDED:
        {
            adv_scan_start();
        } break;

        case PM_EVT_LOCAL_DB_CACHE_APPLY_FAILED:
        {
            // The local database has likely changed, send service changed indications.
            pm_local_database_has_changed();
        } break;

        case PM_EVT_PEER_DATA_UPDATE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peer_data_update_failed.error);
        } break;

        case PM_EVT_PEER_DELETE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peer_delete_failed.error);
        } break;

        case PM_EVT_PEERS_DELETE_FAILED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.peers_delete_failed_evt.error);
        } break;

        case PM_EVT_ERROR_UNEXPECTED:
        {
            // Assert.
            APP_ERROR_CHECK(p_evt->params.error_unexpected.error);
        } break;

        case PM_EVT_CONN_SEC_START:
        case PM_EVT_PEER_DATA_UPDATE_SUCCEEDED:
        case PM_EVT_PEER_DELETE_SUCCEEDED:
        case PM_EVT_LOCAL_DB_CACHE_APPLIED:
        case PM_EVT_SERVICE_CHANGED_IND_SENT:
        case PM_EVT_SERVICE_CHANGED_IND_CONFIRMED:
        default:
            break;
    }
}



/**@brief Function for handling characters received by the Nordic UART Service.
 *
 * @details This function takes a list of characters of length data_len and prints the characters out on UART.
 *          If @ref ECHOBACK_BLE_UART_DATA is set, the data is sent back to sender.
 */
static void ble_nus_chars_received_uart_print(uint8_t * p_data, uint16_t data_len)
{
    ret_code_t ret_val;

    NRF_LOG_DEBUG("Receiving data.");
    NRF_LOG_HEXDUMP_DEBUG(p_data, data_len);

    for (uint32_t i = 0; i < data_len; i++)
    {
        do
        {
            ret_val = app_uart_put(p_data[i]);
            if ((ret_val != NRF_SUCCESS) && (ret_val != NRF_ERROR_BUSY))
            {
                NRF_LOG_ERROR("app_uart_put failed for index 0x%04x.", i);
                APP_ERROR_CHECK(ret_val);
            }
        } while (ret_val == NRF_ERROR_BUSY);
    }
    if (p_data[data_len-1] == '\r')
    {
        while (app_uart_put('\n') == NRF_ERROR_BUSY);
    }
    if (ECHOBACK_BLE_UART_DATA)
    {
        // Send data back to peripheral.
        do
        {
            ret_val = ble_nus_c_string_send(&m_ble_nus_c, p_data, data_len);
            if ((ret_val != NRF_SUCCESS) && (ret_val != NRF_ERROR_BUSY))
            {
                NRF_LOG_ERROR("Failed sending NUS message. Error 0x%x. ", ret_val);
                APP_ERROR_CHECK(ret_val);
            }
        } while (ret_val == NRF_ERROR_BUSY);
    }
}


/**@brief   Function for handling app_uart events.
 *
 * @details This function will receive a single character from the app_uart module and append it to
 *          a string. The string will be be sent over BLE when the last character received was a
 *          'new line' '\n' (hex 0x0A) or if the string has reached the maximum data length.
 */
/**@snippet [Handling the data received over UART] */
void uart_event_handle(app_uart_evt_t * p_event)
{
    static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
    static uint8_t index = 0;
    uint32_t       err_code;

    switch (p_event->evt_type)
    {
        case APP_UART_DATA_READY:
            UNUSED_VARIABLE(app_uart_get(&data_array[index]));
            index++;

            if ((data_array[index - 1] == '\n') || (index >= (m_ble_nus_max_data_len)))
            {
                NRF_LOG_DEBUG("Ready to send data over BLE NUS");
                NRF_LOG_HEXDUMP_DEBUG(data_array, index);

                do
                {
                    uint16_t length = (uint16_t)index;
                    err_code = ble_nus_string_send(&m_nus, data_array, &length);
                    if ( (err_code != NRF_ERROR_INVALID_STATE) && (err_code != NRF_ERROR_BUSY) )
                    {
                        APP_ERROR_CHECK(err_code);
                    }
                } while (err_code == NRF_ERROR_BUSY);

                index = 0;
            }
            break;

        case APP_UART_COMMUNICATION_ERROR:
            APP_ERROR_HANDLER(p_event->data.error_communication);
            break;

        case APP_UART_FIFO_ERROR:
            APP_ERROR_HANDLER(p_event->data.error_code);
            break;

        default:
            break;
    }
}
/**@snippet [Handling the data received over UART] */



/**@brief Callback handling NUS Client events.
 *
 * @details This function is called to notify the application of NUS client events.
 *
 * @param[in]   p_ble_nus_c   NUS Client Handle. This identifies the NUS client
 * @param[in]   p_ble_nus_evt Pointer to the NUS Client event.
 */

/**@snippet [Handling events from the ble_nus_c module] */
static void ble_nus_c_evt_handler(ble_nus_c_t * p_ble_nus_c, ble_nus_c_evt_t const * p_ble_nus_evt)
{
    uint32_t err_code;
	
    switch (p_ble_nus_evt->evt_type)
    {
        case BLE_NUS_C_EVT_DISCOVERY_COMPLETE:
            printf("Discovery complete.\r\n");
            err_code = ble_nus_c_handles_assign(p_ble_nus_c, p_ble_nus_evt->conn_handle, &p_ble_nus_evt->handles);
            APP_ERROR_CHECK(err_code);

            err_code = ble_nus_c_tx_notif_enable(p_ble_nus_c);
            APP_ERROR_CHECK(err_code);
            printf("Connected to device with Nordic UART Service.\r\n");
            break;

        case BLE_NUS_C_EVT_NUS_TX_EVT:
            ble_nus_chars_received_uart_print(p_ble_nus_evt->p_data, p_ble_nus_evt->data_len);
            break;

        case BLE_NUS_C_EVT_DISCONNECTED:
            printf("Disconnected.\r\n");
            scan_start();
            break;

			}
    
}
/**@snippet [Handling events from the ble_nus_c module] */



///**@brief Function for searching a UUID in the advertisement packets.
// *

/**@brief Reads an advertising report and checks if a UUID is present in the service list.
 *
 * @details The function is able to search for 16-bit, 32-bit and 128-bit service UUIDs.
 *          To see the format of a advertisement packet, see
 *          https://www.bluetooth.org/Technical/AssignedNumbers/generic_access_profile.htm
 *
 * @param[in]   p_target_uuid The UUID to search for.
 * @param[in]   p_adv_report  Pointer to the advertisement report.
 *
 * @retval      true if the UUID is present in the advertisement report. Otherwise false
 */
static bool is_uuid_present(ble_uuid_t               const * p_target_uuid,
                            ble_gap_evt_adv_report_t const * p_adv_report)
{
    ret_code_t   err_code;
    ble_uuid_t   extracted_uuid;
    uint16_t     index  = 0;
    uint8_t    * p_data = (uint8_t *)p_adv_report->data;

    while (index < p_adv_report->dlen)
    {
        uint8_t field_length = p_data[index];
        uint8_t field_type   = p_data[index + 1];

        if (   (field_type == BLE_GAP_AD_TYPE_16BIT_SERVICE_UUID_MORE_AVAILABLE)
            || (field_type == BLE_GAP_AD_TYPE_16BIT_SERVICE_UUID_COMPLETE))
        {
            for (uint32_t i = 0; i < (field_length / UUID16_SIZE); i++)
            {
                err_code = sd_ble_uuid_decode(UUID16_SIZE,
                                              &p_data[i * UUID16_SIZE + index + 2],
                                              &extracted_uuid);

                if (err_code == NRF_SUCCESS)
                {
                    if (extracted_uuid.uuid == p_target_uuid->uuid)
                    {
                        return true;
                    }
                }
            }
        }
        else if (   (field_type == BLE_GAP_AD_TYPE_32BIT_SERVICE_UUID_MORE_AVAILABLE)
                 || (field_type == BLE_GAP_AD_TYPE_32BIT_SERVICE_UUID_COMPLETE))
        {
            for (uint32_t i = 0; i < (field_length / UUID32_SIZE); i++)
            {
                err_code = sd_ble_uuid_decode(UUID32_SIZE,
                                              &p_data[i * UUID32_SIZE + index + 2],
                                              &extracted_uuid);

                if (err_code == NRF_SUCCESS)
                {
                    if (   (extracted_uuid.uuid == p_target_uuid->uuid)
                        && (extracted_uuid.type == p_target_uuid->type))
                    {
                        return true;
                    }
                }
            }
        }

        else if (   (field_type == BLE_GAP_AD_TYPE_128BIT_SERVICE_UUID_MORE_AVAILABLE)
                 || (field_type == BLE_GAP_AD_TYPE_128BIT_SERVICE_UUID_COMPLETE))
        {
            err_code = sd_ble_uuid_decode(UUID128_SIZE, &p_data[index + 2], &extracted_uuid);
            if (err_code == NRF_SUCCESS)
            {
                if (   (extracted_uuid.uuid == p_target_uuid->uuid)
                    && (extracted_uuid.type == p_target_uuid->type))
                {
                    return true;
                }
            }
        }
        index += field_length + 1;
    }
    return false;
}


/**@brief Function for handling BLE events.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 * @param[in]   p_context   Unused.
 */
static void  on_ble_central_evt(ble_evt_t const * p_ble_evt)
{
    ret_code_t            err_code;
    ble_gap_evt_t const * p_gap_evt = &p_ble_evt->evt.gap_evt;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_ADV_REPORT:
        {
            ble_gap_evt_adv_report_t const * p_adv_report = &p_gap_evt->params.adv_report;

            if (is_uuid_present(&m_nus_uuid, p_adv_report))
            {

                err_code = sd_ble_gap_connect(&p_adv_report->peer_addr,
                                              &m_scan_params,
                                              &m_connection_param,
                                              APP_BLE_CONN_CFG_TAG);

                if (err_code == NRF_SUCCESS)
                {
                    // scan is automatically stopped by the connect
                    err_code = bsp_indication_set(BSP_INDICATE_IDLE);
                    APP_ERROR_CHECK(err_code);
                    NRF_LOG_INFO("Connecting to target %02x%02x%02x%02x%02x%02x",
                             p_adv_report->peer_addr.addr[0],
                             p_adv_report->peer_addr.addr[1],
                             p_adv_report->peer_addr.addr[2],
                             p_adv_report->peer_addr.addr[3],
                             p_adv_report->peer_addr.addr[4],
                             p_adv_report->peer_addr.addr[5]
                             );
                }
            }
        }break; // BLE_GAP_EVT_ADV_REPORT

        case BLE_GAP_EVT_CONNECTED:
            printf("Connected to target\r\n");
            err_code = ble_nus_c_handles_assign(&m_ble_nus_c, p_ble_evt->evt.gap_evt.conn_handle, NULL);
            APP_ERROR_CHECK(err_code);

            err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
            APP_ERROR_CHECK(err_code); 
            // start discovery of services. The NUS Client waits for a discovery result
            err_code = ble_db_discovery_start(&m_db_discovery, p_ble_evt->evt.gap_evt.conn_handle);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GAP_EVT_TIMEOUT:
            if (p_gap_evt->params.timeout.src == BLE_GAP_TIMEOUT_SRC_SCAN)
            {
                printf("Scan timed out.\r\n");
                scan_start();
            }
            else if (p_gap_evt->params.timeout.src == BLE_GAP_TIMEOUT_SRC_CONN)
            {
                printf("Connection Request timed out.\r\n");
            }
            break;

        case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
            // Pairing not supported
            err_code = sd_ble_gap_sec_params_reply(p_ble_evt->evt.gap_evt.conn_handle, BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP, NULL, NULL);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
            // Accepting parameters requested by peer.
            err_code = sd_ble_gap_conn_param_update(p_gap_evt->conn_handle,
                                                    &p_gap_evt->params.conn_param_update_request.conn_params);
            APP_ERROR_CHECK(err_code);
            break;

#if defined(S132)
        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_DEBUG("PHY update request.");
            ble_gap_phys_t const phys =
            {
                .rx_phys = BLE_GAP_PHY_AUTO,
                .tx_phys = BLE_GAP_PHY_AUTO,
            };
            err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
            APP_ERROR_CHECK(err_code);
        } break;
#endif

        case BLE_GATTC_EVT_TIMEOUT:
            // Disconnect on GATT Client timeout event.
          printf("GATT Client Timeout.\r\n");
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_TIMEOUT:
            // Disconnect on GATT Server timeout event.
            printf("GATT Server Timeout.\r\n");
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        default:
            break;
    }
}




/**@brief Function for handling BLE events.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 * @param[in]   p_context   Unused.
 */
static void on_ble_peripheral_evt(ble_evt_t const * p_ble_evt)
{
    uint32_t err_code;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            printf("peripheral Connected\r\n");
            bsp_board_led_off(PERIPHERAL_ADVERTISING_LED);
            bsp_board_led_on(PERIPHERAL_CONNECTED_LED);
            m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            printf("peripheral Disconnected\r\n");
             bsp_board_led_off(PERIPHERAL_CONNECTED_LED);
				    bsp_board_led_on(PERIPHERAL_ADVERTISING_LED);
            m_conn_handle = BLE_CONN_HANDLE_INVALID;
            break;

#if defined(S132)
        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_DEBUG("PHY update request.");
            ble_gap_phys_t const phys =
            {
                .rx_phys = BLE_GAP_PHY_AUTO,
                .tx_phys = BLE_GAP_PHY_AUTO,
            };
            err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
            APP_ERROR_CHECK(err_code);
        } break;
#endif

        case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
            // Pairing not supported
            err_code = sd_ble_gap_sec_params_reply(m_conn_handle, BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP, NULL, NULL);
            APP_ERROR_CHECK(err_code);
            break;

         case BLE_GAP_EVT_DATA_LENGTH_UPDATE_REQUEST:
        {
            ble_gap_data_length_params_t dl_params;

            // Clearing the struct will effectivly set members to @ref BLE_GAP_DATA_LENGTH_AUTO
            memset(&dl_params, 0, sizeof(ble_gap_data_length_params_t));
            err_code = sd_ble_gap_data_length_update(p_ble_evt->evt.gap_evt.conn_handle, &dl_params, NULL);
            APP_ERROR_CHECK(err_code);
        } break;

        case BLE_GATTS_EVT_SYS_ATTR_MISSING:
            // No system attributes have been stored.
            err_code = sd_ble_gatts_sys_attr_set(m_conn_handle, NULL, 0, 0);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTC_EVT_TIMEOUT:
            // Disconnect on GATT Client timeout event.
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_TIMEOUT:
            // Disconnect on GATT Server timeout event.
            err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
                                             BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_EVT_USER_MEM_REQUEST:
            err_code = sd_ble_user_mem_reply(p_ble_evt->evt.gattc_evt.conn_handle, NULL);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
        {
            ble_gatts_evt_rw_authorize_request_t  req;
            ble_gatts_rw_authorize_reply_params_t auth_reply;

            req = p_ble_evt->evt.gatts_evt.params.authorize_request;

            if (req.type != BLE_GATTS_AUTHORIZE_TYPE_INVALID)
            {
                if ((req.request.write.op == BLE_GATTS_OP_PREP_WRITE_REQ)     ||
                    (req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_NOW) ||
                    (req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL))
                {
                    if (req.type == BLE_GATTS_AUTHORIZE_TYPE_WRITE)
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
                    }
                    else
                    {
                        auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_READ;
                    }
                    auth_reply.params.write.gatt_status = APP_FEATURE_NOT_SUPPORTED;
                    err_code = sd_ble_gatts_rw_authorize_reply(p_ble_evt->evt.gatts_evt.conn_handle,
                                                               &auth_reply);
                    APP_ERROR_CHECK(err_code);
                }
            }
        } break; // BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST

        default:
            // No implementation needed.
            break;
    }
}


/**@brief Function for handling advertising events.
 *
 * @param[in] ble_adv_evt  Advertising event.
 */
static void on_adv_evt(ble_adv_evt_t ble_adv_evt)
{
    switch (ble_adv_evt)
    {
        case BLE_ADV_EVT_FAST:
        {
            printf("Fast advertising.\r\n");
            bsp_board_led_on(PERIPHERAL_ADVERTISING_LED);
        } break;

        case BLE_ADV_EVT_IDLE:
        {
            ret_code_t err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
            APP_ERROR_CHECK(err_code);
        } break;

        default:
            // No implementation needed.
            break;
    }
}

/**@brief Function for checking if a bluetooth stack event is an advertising timeout.
 *
 * @param[in] p_ble_evt Bluetooth stack event.
 */
static bool ble_evt_is_advertising_timeout(ble_evt_t const * p_ble_evt)
{
  return (   (p_ble_evt->header.evt_id == BLE_GAP_EVT_TIMEOUT)
          && (p_ble_evt->evt.gap_evt.params.timeout.src == BLE_GAP_TIMEOUT_SRC_ADVERTISING));
}


static void db_discovery_retry(void)
{
    m_retry_db_disc = false;
    NRF_LOG_INFO("Retrying DB discovery on handle 0x%x.", m_conn_handle_to_disc);
    memset(&m_db_discovery, 0x00, sizeof(m_db_discovery));
    ret_code_t err_code = ble_db_discovery_start(&m_db_discovery, m_conn_handle_to_disc);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling BLE events.
 *
 * @param[in]   p_ble_evt   Bluetooth stack event.
 * @param[in]   p_context   Unused.
 */
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
    uint16_t conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
    uint16_t role        = ble_conn_state_role(conn_handle);

    // Based on the role this device plays in the connection, dispatch to the right handler.
    if (role == BLE_GAP_ROLE_PERIPH || ble_evt_is_advertising_timeout(p_ble_evt))
    {
			
			  on_ble_peripheral_evt(p_ble_evt);
        ble_nus_on_ble_evt ( p_ble_evt,&m_nus);
 
    }
    else if ((role == BLE_GAP_ROLE_CENTRAL) || (p_ble_evt->header.evt_id == BLE_GAP_EVT_ADV_REPORT))
    {
     
		  	on_ble_central_evt(p_ble_evt);
        ble_nus_c_on_ble_evt(p_ble_evt,&m_ble_nus_c );
			  
	}
}

/**@brief Function for initializing the NUS Client. */
static void nus_c_init(void)
{
    ret_code_t       err_code;
    ble_nus_c_init_t init;

    init.evt_handler = ble_nus_c_evt_handler;

    err_code = ble_nus_c_init(&m_ble_nus_c, &init);
	printf("\r\n error code=%d",err_code);
	
    APP_ERROR_CHECK(err_code);
	 
}


/**@brief Function for initializing the BLE stack.
 *
 * @details Initializes the SoftDevice and the BLE event interrupts.
 */
static void ble_stack_init(void)
{
    ret_code_t err_code;

    err_code = nrf_sdh_enable_request(); 
	 
	  
    APP_ERROR_CHECK(err_code);

    // Configure the BLE stack using the default settings.
    // Fetch the start address of the application RAM.
    uint32_t ram_start = 0;
    err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
	   
    APP_ERROR_CHECK(err_code);

    // Enable BLE stack.
    err_code = nrf_sdh_ble_enable(&ram_start);
	   
    APP_ERROR_CHECK(err_code);

    // Register a handler for BLE events.
    NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
}


/**@brief Function for the Peer Manager initialization.
 */
static void peer_manager_init(void)
{
    ble_gap_sec_params_t sec_param;
    ret_code_t err_code;

    err_code = pm_init();
    APP_ERROR_CHECK(err_code);

    memset(&sec_param, 0, sizeof(ble_gap_sec_params_t));

    // Security parameters to be used for all security procedures.
    sec_param.bond           = SEC_PARAM_BOND;
    sec_param.mitm           = SEC_PARAM_MITM;
    sec_param.lesc           = SEC_PARAM_LESC;
    sec_param.keypress       = SEC_PARAM_KEYPRESS;
    sec_param.io_caps        = SEC_PARAM_IO_CAPABILITIES;
    sec_param.oob            = SEC_PARAM_OOB;
    sec_param.min_key_size   = SEC_PARAM_MIN_KEY_SIZE;
    sec_param.max_key_size   = SEC_PARAM_MAX_KEY_SIZE;
    sec_param.kdist_own.enc  = 1;
    sec_param.kdist_own.id   = 1;
    sec_param.kdist_peer.enc = 1;
    sec_param.kdist_peer.id  = 1;

    err_code = pm_sec_params_set(&sec_param);
    APP_ERROR_CHECK(err_code);

    err_code = pm_register(pm_evt_handler);
    APP_ERROR_CHECK(err_code);
}


/**@brief Clear bond information from persistent storage.
 */
static void delete_bonds(void)
{
    ret_code_t err_code;

    NRF_LOG_INFO("Erase bonds!");

    err_code = pm_peers_delete();
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for initializing buttons and leds.
 *
 * @param[out] p_erase_bonds  Will be true if the clear bonding button was pressed to
 *                            wake the application up.
 */
static void buttons_leds_init(bool * p_erase_bonds)
{
    ret_code_t err_code;
    bsp_event_t startup_event;

    err_code = bsp_init(BSP_INIT_LED | BSP_INIT_BUTTONS, NULL);
	  
    APP_ERROR_CHECK(err_code);

    err_code = bsp_btn_ble_init(NULL, &startup_event);
    APP_ERROR_CHECK(err_code);

    *p_erase_bonds = (startup_event == BSP_EVENT_CLEAR_BONDING_DATA);
}


/**@brief Function for the GAP initialization.
 *
 * @details This function sets up all the necessary GAP (Generic Access Profile) parameters of the
 *          device including the device name, appearance, and the preferred connection parameters.
 */
static void gap_params_init(void)
{
    ret_code_t              err_code;
    ble_gap_conn_params_t   gap_conn_params;
    ble_gap_conn_sec_mode_t sec_mode;

    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);

    err_code = sd_ble_gap_device_name_set(&sec_mode,
                                          (const uint8_t *)DEVICE_NAME,
                                          strlen(DEVICE_NAME));
    APP_ERROR_CHECK(err_code);

    memset(&gap_conn_params, 0, sizeof(gap_conn_params));

    gap_conn_params.min_conn_interval = MIN_CONNECTION_INTERVAL;
    gap_conn_params.max_conn_interval = MAX_CONNECTION_INTERVAL;
    gap_conn_params.slave_latency     = SLAVE_LATENCY;
    gap_conn_params.conn_sup_timeout  = SUPERVISION_TIMEOUT;

    err_code = sd_ble_gap_ppcp_set(&gap_conn_params);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for initializing the GATT module.
 */
static void gatt_init(void)
{
    ret_code_t err_code = nrf_ble_gatt_init(&m_gatt, NULL);
    APP_ERROR_CHECK(err_code);
}




///**@brief   Function for handling app_uart events.
// *
// * @details This function will receive a single character from the app_uart module and append it to
// *          a string. The string will be be sent over BLE when the last character received was a
// *          'new line' i.e '\r\n' (hex 0x0D) or if the string has reached a length of
// *          @ref NUS_MAX_DATA_LENGTH.
// */
///**@snippet [Handling the data received over UART] */
//void uart_event_handle(app_uart_evt_t * p_event)
//{
//	 
//	 // printf("entered uart eventhandler\r\n");
//    static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
//    static uint8_t index = 0;
//    uint32_t       err_code;

//    switch (p_event->evt_type)
//    {
//        case APP_UART_DATA_READY:
//            UNUSED_VARIABLE(app_uart_get(&data_array[index]));
//				    cmd[index]=data_array[index];
//            index++;

//            if ((data_array[index - 1] == '\n') || (index >= (BLE_NUS_MAX_DATA_LEN)))
//            {
//							
//							  if((strncmp((char*)data_array,"bothon",6)==0))
//								 {
//									   //bothon();
//									 //printf("\r\n entered in adv_sc");
//									   nrf_delay_ms(10);
//								 }
//								 
//								 
//							  else if((strncmp((char*)data_array,"bothoff",7)==0))
//								 {
//		                     both_off();
//								 }
//								 
//								 if((strncmp((char *)data_array,"centralon",9)==0))
//								 {
//									 
////									 nrf_delay_ms(10);
//									   adv_scan_start();
//									 
//								 }
//								 
//								 else if((strncmp((char *)data_array,"advon",5)==0))
//								 {
//									 printf("\r\n peripheral=%s",data_array);
//									 nrf_delay_ms(10);
//									 adv_on();
//								 }
////                err_code = ble_nus_string_send(&m_nus, data_array, index);
////							  err_code=ble_nus_c_string_send(&m_ble_nus_c,data_array,index);//added for central
////                if (err_code != NRF_ERROR_INVALID_STATE)
////                {
////                    APP_ERROR_CHECK(err_code);
////                }
//              
//								   memset(&cmd, 0, sizeof(0));
////								  printf("\r\n command1=%s",cmd);
//                  index = 0;
//            }
//            break;

//        case APP_UART_COMMUNICATION_ERROR:
//            APP_ERROR_HANDLER(p_event->data.error_communication);
//            break;

//        case APP_UART_FIFO_ERROR:
//            APP_ERROR_HANDLER(p_event->data.error_code);
//            break;

//        default:
//            break;
//    }
//}
///**@snippet [Handling the data received over UART] */





/**@brief  Function for initializing the UART module.
 */
/**@snippet [UART Initialization] */
static void uart_init(void)
{
    uint32_t err_code;
    const app_uart_comm_params_t comm_params =
    {
        .rx_pin_no    = RX_PIN_NUMBER,
        .tx_pin_no    = TX_PIN_NUMBER,
        .rts_pin_no   = RTS_PIN_NUMBER,
        .cts_pin_no   = CTS_PIN_NUMBER,
        .flow_control = APP_UART_FLOW_CONTROL_DISABLED,
        .use_parity   = false,
        .baud_rate    = UART_BAUDRATE_BAUDRATE_Baud115200
    };

    APP_UART_FIFO_INIT( &comm_params,
                       UART_RX_BUF_SIZE,
                       UART_TX_BUF_SIZE,
                       uart_event_handle,
                       APP_IRQ_PRIORITY_LOWEST,
                       err_code);
APP_ERROR_CHECK(err_code);
}
/**@snippet [UART Initialization] */


/**@brief Function for initializing the Connection Parameters module.
 */
static void conn_params_init(void)
{
    ret_code_t             err_code;
    ble_conn_params_init_t cp_init;

    memset(&cp_init, 0, sizeof(cp_init));

    cp_init.p_conn_params                  = NULL;
    cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
    cp_init.next_conn_params_update_delay  = NEXT_CONN_PARAMS_UPDATE_DELAY;
    cp_init.max_conn_params_update_count   = MAX_CONN_PARAMS_UPDATE_COUNT;
    cp_init.start_on_notify_cccd_handle    = BLE_CONN_HANDLE_INVALID; // Start upon connection.
    cp_init.disconnect_on_fail             = true;
    cp_init.evt_handler                    = NULL;  // Ignore events.
    cp_init.error_handler                  = conn_params_error_handler;

    err_code = ble_conn_params_init(&cp_init);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling database discovery events.
 *
 * @details This function is callback function to handle events from the database discovery module.
 *          Depending on the UUIDs that are discovered, this function should forward the events
 *          to their respective services.
 *
 * @param[in] p_event  Pointer to the database discovery event.
 */
static void db_disc_handler(ble_db_discovery_evt_t * p_evt)
{
     ble_nus_c_on_db_disc_evt(&m_ble_nus_c, p_evt);
	
    if (   (p_evt->evt_type == BLE_DB_DISCOVERY_COMPLETE)
        && (m_retry_db_disc)
        && (m_conn_handle_to_disc != BLE_CONN_HANDLE_INVALID))
    {
        // DB discovery cannot be restarted directly here because the
        // database discovery structure would need to be zeroed, however it is still
        // needed by the module (it might have pending events to send).
        // Let's set a flag and re-run DB discovery when we receive the next BLE event.

        NRF_LOG_INFO("DB discovery can be retried.");
        m_do_retry_db_disc = true;
    }
}


/**
 * @brief Database discovery initialization.
 */
static void db_discovery_init(void)
{
    ret_code_t err_code = ble_db_discovery_init(db_disc_handler);
    APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling the data from the Nordic UART Service.
 *
 * @details This function will process the data received from the Nordic UART BLE Service and send
 *          it to the UART module.
 *
 * @param[in] p_nus    Nordic UART Service structure.
 * @param[in] p_data   Data to be send to UART module.
 * @param[in] length   Length of the data.
 */
/**@snippet [Handling the data received over BLE] */
static void nus_data_handler(ble_nus_evt_t * p_evt)
{

    if (p_evt->type == BLE_NUS_EVT_RX_DATA)
    {
        uint32_t err_code;

        NRF_LOG_DEBUG("Received data from BLE NUS. Writing data on UART.");
        NRF_LOG_HEXDUMP_DEBUG(p_evt->params.rx_data.p_data, p_evt->params.rx_data.length);

        for (uint32_t i = 0; i < p_evt->params.rx_data.length; i++)
        {
            do
            {
                err_code = app_uart_put(p_evt->params.rx_data.p_data[i]);
                if ((err_code != NRF_SUCCESS) && (err_code != NRF_ERROR_BUSY))
                {
                    NRF_LOG_ERROR("Failed receiving NUS message. Error 0x%x. ", err_code);
                    APP_ERROR_CHECK(err_code);
                }
            } while (err_code == NRF_ERROR_BUSY);
        }
        if (p_evt->params.rx_data.p_data[p_evt->params.rx_data.length-1] == '\r')
        {
            while (app_uart_put('\n') == NRF_ERROR_BUSY);
        }
    }

}
/**@snippet [Handling the data received over BLE] */

/**@brief Function for initializing services that will be used by the application.
 *
 * @details Initialize the Heart Rate, Battery and Device Information services.
 */
static void services_init(void)
{
   uint32_t       err_code;
    ble_nus_init_t nus_init;

    memset(&nus_init, 0, sizeof(nus_init));

    nus_init.data_handler = nus_data_handler;

    err_code = ble_nus_init(&m_nus, &nus_init);
    APP_ERROR_CHECK(err_code);
}



/**@brief Function for initializing the Advertising functionality.
 */
static void advertising_init(void)
{
    ret_code_t             err_code;
    ble_advertising_init_t init;

    memset(&init, 0, sizeof(init));

    init.advdata.name_type               = BLE_ADVDATA_FULL_NAME;
    init.advdata.include_appearance      = true;
    init.advdata.flags                   = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
    init.advdata.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
    init.advdata.uuids_complete.p_uuids  = m_adv_uuids;

    init.config.ble_adv_fast_enabled  = true;
    init.config.ble_adv_fast_interval = APP_ADV_INTERVAL;
    init.config.ble_adv_fast_timeout  = APP_ADV_TIMEOUT_IN_SECONDS;

    init.evt_handler = on_adv_evt;

    err_code = ble_advertising_init(&m_advertising, &init);
    APP_ERROR_CHECK(err_code);

    ble_advertising_conn_cfg_tag_set(&m_advertising, APP_BLE_CONN_CFG_TAG);
}


/**@brief Function for initializing logging.
 */
static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(NULL);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();
}


/**@brief Function for initializing the timer.
 */
static void timer_init(void)
{
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);
}


/** @brief Function to sleep until a BLE event is received by the application.
 */
static void power_manage(void)
{
    ret_code_t err_code = sd_app_evt_wait();
    APP_ERROR_CHECK(err_code);
}


int main(void)
{
    bool erase_bonds;
     
    //log_init();
	 
    timer_init();
	  uart_init();
	 
		
	  buttons_leds_init(&erase_bonds);
//	  printf("\r\n after leds init");
//	  nrf_delay_ms(100);
    ble_stack_init();
//	  printf("\r\n after stack init");
//	  nrf_delay_ms(100);
    gap_params_init();
//	  printf("\r\n after gap_par init");
//	  nrf_delay_ms(100);
    gatt_init();
//	  printf("\r\n after gatt init");
//	  nrf_delay_ms(100);
    conn_params_init();
//		printf("\r\n after conn_par init");
//	  nrf_delay_ms(100);
    db_discovery_init();
//		printf("\r\n after db_disc init");
//	  nrf_delay_ms(100);
    peer_manager_init();
//		printf("\r\n after peer_mng init");
//	  nrf_delay_ms(100);
    nus_c_init();
//		printf("\r\n after nus_c init");
//	  nrf_delay_ms(100);
   // rscs_c_init();
    services_init();
//		printf("\r\n after services init");
//	  nrf_delay_ms(100);
    advertising_init();
//		printf("\r\n after advertising init");
//	  nrf_delay_ms(100);

    if (erase_bonds == true)
    {
        // Scanning and advertising is done upon PM_EVT_PEERS_DELETE_SUCCEEDED event.
        delete_bonds();
        // Scanning and advertising is done by
    }
    else
    {
        adv_scan_start();
    }

    printf("Relay example started.");

    for (;;)
    {
        if (NRF_LOG_PROCESS() == false)
        {
            // Wait for BLE events.
            power_manage();
        }
    }
}
The above is my main code.
Could you please help me in solve this issue?
Thanks in advance.