Want MPU6050 Value through BLE

I get MPU6050 Accelerometer value zero when I using BLE. MAy be I am not abIing to read the register value.Here I attached my code 

#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "ble_hci.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "nrf_sdh.h"
#include "nrf_sdh_soc.h"
#include "nrf_sdh_ble.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_qwr.h"
#include "app_timer.h"
#include "ble_nus.h"
#include "app_uart.h"
#include "app_util_platform.h"
#include "bsp_btn_ble.h"
#include "nrf_pwr_mgmt.h"

#if defined (UART_PRESENT)
#include "nrf_uart.h"
#endif
#if defined (UARTE_PRESENT)
#include "nrf_uarte.h"
#endif

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

#include "nrf_drv_twi.h"
#include "mpu6050.h"


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

#define DEVICE_NAME                     "Nordic_UART"                               /**< Name of device. Will be included in the advertising data. */
#define NUS_SERVICE_UUID_TYPE           BLE_UUID_TYPE_VENDOR_BEGIN                  /**< UUID type for the Nordic UART Service (vendor specific). */

#define APP_BLE_OBSERVER_PRIO           3                                           /**< Application's BLE observer priority. You shouldn't need to modify this value. */

#define APP_ADV_INTERVAL                64                                          /**< The advertising interval (in units of 0.625 ms. This value corresponds to 40 ms). */

#define APP_ADV_DURATION                18000                                       /**< The advertising duration (180 seconds) in units of 10 milliseconds. */

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(20, UNIT_1_25_MS)             /**< Minimum acceptable connection interval (20 ms), Connection interval uses 1.25 ms units. */
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(75, UNIT_1_25_MS)             /**< Maximum acceptable connection interval (75 ms), Connection interval uses 1.25 ms units. */
#define SLAVE_LATENCY                   0                                           /**< Slave latency. */
#define CONN_SUP_TIMEOUT                MSEC_TO_UNITS(4000, UNIT_10_MS)             /**< Connection supervisory timeout (4 seconds), Supervision Timeout uses 10 ms units. */
#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 DEAD_BEEF                       0xDEADBEEF                                  /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */

#define UART_TX_BUF_SIZE                256                                         /**< UART TX buffer size. */
#define UART_RX_BUF_SIZE                256                                         /**< UART RX buffer size. */


BLE_NUS_DEF(m_nus, NRF_SDH_BLE_TOTAL_LINK_COUNT);                                   /**< BLE NUS service instance. */
NRF_BLE_GATT_DEF(m_gatt);                                                           /**< GATT module instance. */
NRF_BLE_QWR_DEF(m_qwr);                                                             /**< Context for the Queued Write module.*/
BLE_ADVERTISING_DEF(m_advertising);                                                 /**< Advertising module instance. */

static uint16_t   m_conn_handle          = BLE_CONN_HANDLE_INVALID;                 /**< Handle of the current connection. */
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 Function for assert macro callback.
 *
 * @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 analyse
 *          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(DEAD_BEEF, line_num, p_file_name);
}

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

/**@brief Function for the GAP initialization.
 *
 * @details This function will set up all the necessary GAP (Generic Access Profile) parameters of
 *          the device. It also sets the permissions and appearance.
 */
static void gap_params_init(void)
{
    uint32_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_CONN_INTERVAL;
    gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
    gap_conn_params.slave_latency     = SLAVE_LATENCY;
    gap_conn_params.conn_sup_timeout  = CONN_SUP_TIMEOUT;

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


/**@brief Function for handling Queued Write Module errors.
 *
 * @details A pointer to this function will be passed to each service which may need to inform the
 *          application about an error.
 *
 * @param[in]   nrf_error   Error code containing information about what went wrong.
 */
static void nrf_qwr_error_handler(uint32_t nrf_error)
{
    APP_ERROR_HANDLER(nrf_error);
}

/**************************************************************************************************************************/
/**@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_evt       Nordic UART Service event.
 */
/**@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);
        }
    }

}
/******************************************************************************************************************/
/*static uint8_t val = 20;
uint16_t sttt = sizeof(val);

uint32_t ble_nus_data_send(ble_nus_t *p_nus, uint8_t val, uint16_t sttt, uint16_t m_conn_handle);
/**@snippet [Handling the data received over BLE] */


/**@brief Function for initializing services that will be used by the application.
 */
static void services_init(void)
{
    uint32_t           err_code;
    ble_nus_init_t     nus_init;
    nrf_ble_qwr_init_t qwr_init = {0};

    // Initialize Queued Write Module.
    qwr_init.error_handler = nrf_qwr_error_handler;

    err_code = nrf_ble_qwr_init(&m_qwr, &qwr_init);
    APP_ERROR_CHECK(err_code);

    // Initialize NUS.
    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 handling an event from the Connection Parameters Module.
 *
 * @details This function will be called for all events in the Connection Parameters Module
 *          which are passed to the application.
 *
 * @note All this function does is to disconnect. This could have been done by simply setting
 *       the disconnect_on_fail config parameter, but instead we use the event handler
 *       mechanism to demonstrate its use.
 *
 * @param[in] p_evt  Event received from the Connection Parameters Module.
 */
static void on_conn_params_evt(ble_conn_params_evt_t * p_evt)
{
    uint32_t err_code;

    if (p_evt->evt_type == BLE_CONN_PARAMS_EVT_FAILED)
    {
        err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
        APP_ERROR_CHECK(err_code);
    }
}


/**@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 Function for initializing the Connection Parameters module.
 */
static void conn_params_init(void)
{
    uint32_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_GATT_HANDLE_INVALID;
    cp_init.disconnect_on_fail             = false;
    cp_init.evt_handler                    = on_conn_params_evt;
    cp_init.error_handler                  = conn_params_error_handler;

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


/**@brief Function for putting the chip into sleep mode.
 *
 * @note This function will not return.
 */
static void sleep_mode_enter(void)
{
    uint32_t err_code = bsp_indication_set(BSP_INDICATE_IDLE);
    APP_ERROR_CHECK(err_code);

    // Prepare wakeup buttons.
    err_code = bsp_btn_ble_sleep_mode_prepare();
    APP_ERROR_CHECK(err_code);

    // Go to system-off mode (this function will not return; wakeup will cause a reset).
    err_code = sd_power_system_off();
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling advertising events.
 *
 * @details This function will be called for advertising events which are passed to the application.
 *
 * @param[in] ble_adv_evt  Advertising event.
 */
static void on_adv_evt(ble_adv_evt_t ble_adv_evt)
{
    uint32_t err_code;

    switch (ble_adv_evt)
    {
        case BLE_ADV_EVT_FAST:
            err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING);
            APP_ERROR_CHECK(err_code);
            break;
        case BLE_ADV_EVT_IDLE:
            sleep_mode_enter();
            break;
        default:
            break;
    }
}


/**@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)
{
    uint32_t err_code;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            NRF_LOG_INFO("Connected");
            err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
            APP_ERROR_CHECK(err_code);
            m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
            err_code = nrf_ble_qwr_conn_handle_assign(&m_qwr, m_conn_handle);
            APP_ERROR_CHECK(err_code);
            break;

        case BLE_GAP_EVT_DISCONNECTED:
            NRF_LOG_INFO("Disconnected");
            // LED indication will be changed when advertising starts.
            m_conn_handle = BLE_CONN_HANDLE_INVALID;
            break;

        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;

        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_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://------------------------------------------------------------>>>PROBLEM
            // 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;

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


/**@brief Function for the SoftDevice initialization.
 *
 * @details This function initializes the SoftDevice and the BLE event interrupt.
 */
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 handling events from the GATT library. */
void gatt_evt_handler(nrf_ble_gatt_t * p_gatt, nrf_ble_gatt_evt_t const * p_evt)
{
    if ((m_conn_handle == p_evt->conn_handle) && (p_evt->evt_id == NRF_BLE_GATT_EVT_ATT_MTU_UPDATED))
    {
        m_ble_nus_max_data_len = p_evt->params.att_mtu_effective - OPCODE_LENGTH - HANDLE_LENGTH;
        NRF_LOG_INFO("Data len is set to 0x%X(%d)", m_ble_nus_max_data_len, m_ble_nus_max_data_len);
    }
    NRF_LOG_DEBUG("ATT MTU exchange completed. central 0x%x peripheral 0x%x",
                  p_gatt->att_mtu_desired_central,
                  p_gatt->att_mtu_desired_periph);
}


/**@brief Function for initializing the GATT library. */
void gatt_init(void)
{
    ret_code_t err_code;

    err_code = nrf_ble_gatt_init(&m_gatt, gatt_evt_handler);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling events from the BSP module.
 *
 * @param[in]   event   Event generated by button press.
 */
void bsp_event_handler(bsp_event_t event)
{
    uint32_t err_code;
    switch (event)
    {
        case BSP_EVENT_SLEEP:
            sleep_mode_enter();
            break;

        case BSP_EVENT_DISCONNECT:
            err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
            if (err_code != NRF_ERROR_INVALID_STATE)
            {
                APP_ERROR_CHECK(err_code);
            }
            break;

        case BSP_EVENT_WHITELIST_OFF:
            if (m_conn_handle == BLE_CONN_HANDLE_INVALID)
            {
                err_code = ble_advertising_restart_without_whitelist(&m_advertising);
                if (err_code != NRF_ERROR_INVALID_STATE)
                {
                    APP_ERROR_CHECK(err_code);
                }
            }
            break;

        default:
            break;
    }
}


/**@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') ||
                (data_array[index - 1] == '\r') ||
                (index >= m_ble_nus_max_data_len))
            {
                if (index > 1)
                {
                    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_data_send(&m_nus, data_array, &length, m_conn_handle);
                        if ((err_code != NRF_ERROR_INVALID_STATE) &&
                            (err_code != NRF_ERROR_RESOURCES) &&
                            (err_code != NRF_ERROR_NOT_FOUND))
                        {
                            APP_ERROR_CHECK(err_code);
                        }
                    } while (err_code == NRF_ERROR_RESOURCES);
                }

                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;
    app_uart_comm_params_t const 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,
#if defined (UART_PRESENT)
        .baud_rate    = NRF_UART_BAUDRATE_115200
#else
        .baud_rate    = NRF_UARTE_BAUDRATE_115200
#endif
    };

    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 Advertising functionality.
 */
static void advertising_init(void)
{
    uint32_t               err_code;
    ble_advertising_init_t init;//THIS IS A STUCTURE

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

    init.advdata.name_type          = BLE_ADVDATA_FULL_NAME;
    init.advdata.include_appearance = false;
    init.advdata.flags              = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;

    init.srdata.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
    init.srdata.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_DURATION;
    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 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)
{
    bsp_event_t startup_event;

    uint32_t err_code = bsp_init(BSP_INIT_LEDS | BSP_INIT_BUTTONS, bsp_event_handler);
    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 initializing the nrf log module.
 */
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 power management.
 */
static void power_management_init(void)
{
    ret_code_t err_code;
    err_code = nrf_pwr_mgmt_init();
    APP_ERROR_CHECK(err_code);
}


/**@brief Function for handling the idle state (main loop).
 *
 * @details If there is no pending log operation, then sleep until next the next event occurs.
 */
static void idle_state_handle(void)
{
    if (NRF_LOG_PROCESS() == false)
    {
        nrf_pwr_mgmt_run();
    }
}


/**@brief Function for starting advertising.
 */
static void advertising_start(void)
{
    uint32_t err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
    APP_ERROR_CHECK(err_code);
}






/*********************************************Accel_value********************************************************************************************************************/

/*Accelarometer value*/

 static int8_t AccValue[3];
static void Acc_Val_read ()
{
  
   int len = sizeof(AccValue)/sizeof(uint8_t);
   ble_nus_data_send(&m_nus,&AccValue, &len, m_conn_handle);//Send data to ble
   nrf_delay_ms(1000);
   NRF_LOG_FLUSH();


}

/************************************************************************************************************************************************************************************/



/**@brief Application main function.
 */
int main(void)
{
    bool erase_bonds;
//static int8_t AccValue[3];
   // Initialize.
    uart_init();
    log_init();
    timers_init();
    buttons_leds_init(&erase_bonds);
    power_management_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();
    advertising_start();
    nrf_delay_ms(100);

    // Start execution.
    //printf("\r\nUART started.\r\n");

    //NRF_LOG_INFO("Debug logging for UART over RTT started.");
   twi_master_init(); // initialize the twi 
   nrf_delay_ms(50); // give some delay

   mpu6050_init();
   nrf_delay_ms(100);


    while(mpu6050_init() == false) // wait until MPU6050 sensor is successfully initialized
   {
      NRF_LOG_INFO("MPU_6050 initialization failed!!!"); // if it failed to initialize then print a message
      nrf_delay_ms(1000);
    }

    NRF_LOG_INFO("MPU6050 Init Successfully!!!"); 

    NRF_LOG_INFO("Reading Values from ACC & GYRO"); // display a message to let the user know that the device is starting to read the values
    nrf_delay_ms(1000);


    // Enter main loop.
    for (;;)
    {
         idle_state_handle();
         nrf_delay_ms(1000);
   
          Acc_Val_read ();
          NRF_LOG_INFO("ACC Values:  x = %d  y = %d  z = %d", AccValue[0], AccValue[1], AccValue[2]); // display the read values
        
       
       

    }
    
}


/**
 * @}
 */

  • Hi there,

    You should include your MPU code so that everyone can see if anything happened in that code. For the attached code, at the first glance I didn't see anything wrong as you're using ble_nus example to send MPU values through BLE.

    I would highly recommend checking this source which provides you codes for MPU and how it was combined with BLE code. Gluck!

    Martinsbl/nrf5-mpu-examples (github.com)

  • here I attached my main file 

    #include <stdbool.h>
    #include <stdint.h>
    #include <string.h>
    #include "nrf_drv_twi.h"
    #include "mpu6050.h"
    
    
    
    
    //Initializing TWI0 instance
    #define TWI_INSTANCE_ID     0
    
    // A flag to indicate the transfer state
    static volatile bool m_xfer_done = false;
    
    
    // Create a Handle for the twi communication
    static const nrf_drv_twi_t m_twi = NRF_DRV_TWI_INSTANCE(TWI_INSTANCE_ID);
    
    
    
    
    //Event Handler
    void twi_handler(nrf_drv_twi_evt_t const * p_event, void * p_context)
    {
        //Check the event to see what type of event occurred
        switch (p_event->type)
        {
            //If data transmission or receiving is finished
    	case NRF_DRV_TWI_EVT_DONE:
            m_xfer_done = true;//Set the flag
            break;
            
            default:
            // do nothing
              break;
        }
    }
    
    
    
    //Initialize the TWI as Master device
    void twi_master_init(void)
    {
        ret_code_t err_code;
    
        // Configure the settings for twi communication
        const nrf_drv_twi_config_t twi_config = {
           .scl                = TWI_SCL_M,  //SCL Pin
           .sda                = TWI_SDA_M,  //SDA Pin
           .frequency          = NRF_DRV_TWI_FREQ_400K, //Communication Speed
           .interrupt_priority = APP_IRQ_PRIORITY_HIGH, //Interrupt Priority(Note: if using Bluetooth then select priority carefully)
           .clear_bus_init     = false //automatically clear bus
        };
    
    
        //A function to initialize the twi communication
        err_code = nrf_drv_twi_init(&m_twi, &twi_config, twi_handler, NULL);
        APP_ERROR_CHECK(err_code);
        
        //Enable the TWI Communication
        nrf_drv_twi_enable(&m_twi);
    }
    
    
    
    /*
       A function to write a Single Byte to MPU6050's internal Register
    */ 
    bool mpu6050_register_write(uint8_t register_address, uint8_t value)
    {
        ret_code_t err_code;
        uint8_t tx_buf[MPU6050_ADDRESS_LEN+1];
    	
        //Write the register address and data into transmit buffer
        tx_buf[0] = register_address;
        tx_buf[1] = value;
    
        //Set the flag to false to show the transmission is not yet completed
        m_xfer_done = false;
        
        //Transmit the data over TWI Bus
        err_code = nrf_drv_twi_tx(&m_twi, MPU6050_ADDRESS, tx_buf, MPU6050_ADDRESS_LEN+1, false);
        
        //Wait until the transmission of the data is finished
        while (m_xfer_done == false)
        {
          }
    
        // if there is no error then return true else return false
        if (NRF_SUCCESS != err_code)
        {
            return false;
        }
        
        return true;	
    }
    
    
    
    
    /*
      A Function to read data from the MPU6050
    */ 
    bool mpu6050_register_read(uint8_t register_address, uint8_t * destination, uint8_t number_of_bytes)
    {
        ret_code_t err_code;
    
        //Set the flag to false to show the receiving is not yet completed
        m_xfer_done = false;
        
        // Send the Register address where we want to write the data
        err_code = nrf_drv_twi_tx(&m_twi, MPU6050_ADDRESS, &register_address, 1, true);
    	  
        //Wait for the transmission to get completed
        while (m_xfer_done == false){}
        
        // If transmission was not successful, exit the function with false as return value
        if (NRF_SUCCESS != err_code)
        {
            return false;
        }
    
        //set the flag again so that we can read data from the MPU6050's internal register
        m_xfer_done = false;
    	  
        // Receive the data from the MPU6050
        err_code = nrf_drv_twi_rx(&m_twi, MPU6050_ADDRESS, destination, number_of_bytes);
    		
        //wait until the transmission is completed
        while (m_xfer_done == false){}
    	
        // if data was successfully read, return true else return false
        if (NRF_SUCCESS != err_code)
        {
            return false;
        }
        
        return true;
    }
    
    
    
    /*
      A Function to verify the product id
      (its a basic test to check if we are communicating with the right slave, every type of I2C Device has 
      a special WHO_AM_I register which holds a specific value, we can read it from the MPU6050 or any device
      to confirm we are communicating with the right device)
    */ 
    bool mpu6050_verify_product_id(void)
    {
        uint8_t who_am_i; // create a variable to hold the who am i value
    
    
        // Note: All the register addresses including WHO_AM_I are declared in 
        // MPU6050.h file, you can check these addresses and values from the
        // datasheet of your slave device.
        if (mpu6050_register_read(ADDRESS_WHO_AM_I, &who_am_i, 1))
        {
            if (who_am_i != MPU6050_WHO_AM_I)
            {
                return false;
            }
            else
            {
                return true;
            }
        }
        else
        {
            return false;
        }
    }
    
    
    /*
      Function to initialize the mpu6050
    */ 
    bool mpu6050_init(void)
    {   
      bool transfer_succeeded = true;
    	
      //Check the id to confirm that we are communicating with the right device
      transfer_succeeded &= mpu6050_verify_product_id();
    	
      if(mpu6050_verify_product_id() == false)
        {
    	return false;
          }
    
      // Set the registers with the required values, see the datasheet to get a good idea of these values
      (void)mpu6050_register_write(MPU_PWR_MGMT1_REG , 0x00); 
      (void)mpu6050_register_write(MPU_SAMPLE_RATE_REG , 0x07); //setting sample rate
      (void)mpu6050_register_write(MPU_CFG_REG , 0x06); 						
      (void)mpu6050_register_write(MPU_INT_EN_REG, 0x00); 
      (void)mpu6050_register_write(MPU_GYRO_CFG_REG , 0x18); 
      (void)mpu6050_register_write(MPU_ACCEL_CFG_REG,0x00);   		
    
      return transfer_succeeded;
    }
    
    
    
    /*
      Read the Gyro values from the MPU6050's internal Registers
    */ 
    bool MPU6050_ReadGyro(int16_t *pGYRO_X , int16_t *pGYRO_Y , int16_t *pGYRO_Z )
    {
      uint8_t buf[6]; 
      
      bool ret = false;	
    	
      if(mpu6050_register_read(MPU6050_GYRO_OUT,  buf, 6) == true)
      {
        *pGYRO_X = (buf[0] << 8) | buf[1];
        if(*pGYRO_X & 0x8000) *pGYRO_X-=65536;
    		
        *pGYRO_Y= (buf[2] << 8) | buf[3];
        if(*pGYRO_Y & 0x8000) *pGYRO_Y-=65536;
    	
        *pGYRO_Z = (buf[4] << 8) | buf[5];
        if(*pGYRO_Z & 0x8000) *pGYRO_Z-=65536;
    		
        ret = true;
    	}
    
      return ret;
    }	
    
    
    
    
    /*
      A Function to read accelerometer's values from the internal registers of MPU6050
    */ 
    bool MPU6050_ReadAcc( int16_t *pACC_X , int16_t *pACC_Y , int16_t *pACC_Z )
    {
      uint8_t buf[6];
      bool ret = false;		
      
      if(mpu6050_register_read(MPU6050_ACC_OUT, buf, 6) == true)
      {
        mpu6050_register_read(MPU6050_ACC_OUT, buf, 6);
        
        *pACC_X = (buf[0] << 8) | buf[1];
        if(*pACC_X & 0x8000) *pACC_X-=65536;
    
        *pACC_Y= (buf[2] << 8) | buf[3];
        if(*pACC_Y & 0x8000) *pACC_Y-=65536;
    
        *pACC_Z = (buf[4] << 8) | buf[5];
        if(*pACC_Z & 0x8000) *pACC_Z-=65536;
    		
        ret = true;
        }
      
      return ret;
    }
    
    
    
    
    
    

  • Hi,

    Looking at your code in the original post, the array AccValue that you print the members of are never set. It is 0 as that is the default value for static variables, and as you never change it, that is what you write. You need to actually read the sensor data and copy that to AccValue before logging it. (in fact, the only mpu6050_* function you call in the code from the original post is mpu6050_init(), and you never try to read as far as I can see.)

  • Can you please tell what to modify in my code...or what function should I call...is it  MPU6050_ReadAcc() function?

  • That is the only function you have that reads accelerometers values, so yes - that must be called. 

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