Data Loss after ble_nus_data_send

[manobala12]

In uart_event_handle case  APP_UART_DATA_READY

UNUSED_VARIABLE(app_uart_get(&data_array[array_index]));

if ((array_index >= 240))

{

   memcpy(Ble_array_to_apk, data_array, sizeof(data_array));

   memset(data_array, 0, sizeof(data_array));

   overflowflag = true;

   length = array_index;

   array_index = 0;

}

In main fun inside for loop 

if (overflowflag == true)

{

  sequence += 1; 

  overflowflag = false;

  err_code = ble_nus_data_send(&m_nus, Ble_array_to_apk, &length, m_conn_handle); 

  memset(Ble_array_to_apk, 0, sizeof(Ble_array_to_apk));

}

err_code is success and also data loss is happen 

In stm32 transmitting 240 bytes with 20ms timer 

[Karl Ylvisaker]

Hello,

err_code is success and also data loss is happen 

It does not seem like you are checking the returned error code for your call to ble_nus_data_send in the shared code.
Please make sure to pass the returned error code to an APP_ERROR_CHECK to be notified whether an error has occured.
In addition, please make sure to have DEBUG added to your preprocessor defines like shown in the included image, as this will make your logger output a detailed error message whenever a non-NRF_SUCCESS error code is passed to an APP_ERROR_CHECK.



Best regards,
Karl

[manobala12]

Yes i am checking 

in stm side i am transmitting 240 with 20ms timer interval gap

if (overflowflag == true)

{

// sent = 'T';

sequence += 1;

overflowflag = false;

// NRF_LOG_INFO("DATA: %s\n", Ble_array_to_apk);

err_code = ble_nus_data_send(&m_nus, Ble_array_to_apk, &length, m_conn_handle);

memset(Ble_array_to_apk, 0, sizeof(Ble_array_to_apk));

NRF_LOG_INFO("err_code: %d,sequence: %d\n", err_code,sequence);

}

NRF view:

[manobala12]

Hello Karl

 Transmitting NO\n  1 time via uart to nrf52840

In NRF side

case APP_UART_DATA_READY:

app_uart_get(&data_array[array_index]);

array_index++;

buff = data_array[0];

NRF_LOG_INFO("DATA: %s",data_array);

if ((data_array[array_index - 1] == '\n'))

{

switch (buff)

{

// err_code = ble_nus_data_send(&m_nus, data_array, &length, m_conn_handle);

// index = 0;

case 'N':

array_index = 0;

// NRF_LOG_INFO("BLE_ON\n");

sequence = 0;

ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);

break;

case 'L':

array_index = 0;

// APP_ERROR_CHECK(err_code);

// NRF_LOG_INFO("BLE_OFF\n");

if ((sent == 67) || (sent == 82))

{

sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);

}

else

sd_ble_gap_adv_stop(m_advertising.adv_handle);

break;

}

}

break;

Result in RTT viewer:

Why it printing 3 time how its working 

[Karl Ylvisaker]

Hello,

Please use the Insert -> Code feature when sharing code here on DevZone.

It is not apparent from the code you have shared why NO is printed multiple times from the UART.
Please share more of the relevant code.

Best regards,
Karl

[manobala12]

#include <stdint.h>
#include <string.h>
#include <stddef.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"
#include "nrf_delay.h"
#include "SEGGER_RTT.h"
#include "nrf_gpio.h"
#include "nrf_drv_uart.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"

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

#define DEVICE_NAME "CPAPR&D"                            /**< 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 5000 /**< 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. */

APP_TIMER_DEF(m_TRAIL_timer_id);
#define TRAIL_TIMER APP_TIMER_TICKS(1000)

static uint8_t array_index = 0;
uint8_t Ble_array_to_apk[240];
static uint8_t data_array[251];
bool overflowflag = false;
bool uartrxrdyflag=false;
uint16_t length;
uint32_t sequence = 0;
uint32_t err_code;

#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. */
uint8_t sent = 0;
int LED_BLINK = NRF_GPIO_PIN_MAP(1, 06);

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}};

static void timeout_handler(void *p_context);
void AppUartHandler();

// static void advertising_start(void);
static void advertising_init(void);
/**@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_INFO("NUS DATA");
    //     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.
 */
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); // for blinking LED1
        APP_ERROR_CHECK(err_code);
        break;
    case BLE_ADV_EVT_IDLE:
        NRF_LOG_INFO("Advertising event received %d", BLE_ADV_EVT_IDLE);
        // sleep_mode_enter();
        sd_ble_gap_adv_stop(m_advertising.adv_handle);
        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:
        sent = 67;
        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:
        sent = 68;
        NRF_LOG_INFO("Disconnected");
        if (p_ble_evt->header.evt_id == BLE_GAP_EVT_DISCONNECTED)
        {
            sd_ble_gap_adv_stop(m_advertising.adv_handle);
        }
        // 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_GAP_EVT_DATA_LENGTH_UPDATE_REQUEST: // FILES
    {
        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:
        NRF_LOG_INFO("GATTC_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:
        NRF_LOG_INFO("GATTS_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_GATTS_EVT_WRITE:
        sent = 82; // Notification Enable
        // NRF_LOG_INFO("UART SERVICES\n");
        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)
{
    // int MacAddr;
    char buff;
    static uint8_t index = 0;
    uint32_t err_code;
    switch (p_event->evt_type)
    {
    case APP_UART_DATA_READY:
        // MacAddr = NRF_FICR->DEVICEADDR[0];
        NRF_LOG_INFO("UART_COMM_READY\n");
        uartrxrdyflag = true;
        // NRF_LOG_INFO("app_uart :%d\n",err_code);
        break;

    case APP_UART_COMMUNICATION_ERROR:
        NRF_LOG_INFO("UART_COMM_ERROR\n");
        // APP_ERROR_HANDLER(p_event->data.error_communication);
        break;

    case APP_UART_FIFO_ERROR:
        NRF_LOG_INFO("UART_FIFO_ERROR\n");
        // APP_ERROR_HANDLER(p_event->data.error_code);
        break;
    case APP_UART_TX_EMPTY:
        uartrxrdyflag = false;
        array_index = 0;
        // memset(data_array, 0, sizeof(data_array));
        // NRF_LOG_INFO("APP_UART_TX_EMPTY\n");

    break;
    default:
        break;
    }
}
void AppUartHandler()
{
    char buff;
        // NRF_LOG_INFO("AppUartHandler\n");

    app_uart_get(&data_array[array_index]);
        array_index++;
        buff = data_array[0];
        NRF_LOG_INFO("DATA: %s",data_array);

        if(data_array[array_index] == 'T')
        {
            memcpy(Ble_array_to_apk, data_array, sizeof(data_array));
            memset(data_array, 0, sizeof(data_array));
            overflowflag = true;
            length = array_index;
            array_index = 0;

        }
        // if ((array_index >= 240))
        // {
        // }    

        if ((data_array[array_index - 1] == '\n'))
        {
            switch (buff)
            {
            //     err_code = ble_nus_data_send(&m_nus, data_array, &length, m_conn_handle);
            // index = 0;
            case 'N':
                array_index = 0;
                memset(data_array, 0, sizeof(data_array));
                // NRF_LOG_INFO("BLE_ON\n");
                sequence = 0;
                ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
                break;
            case 'L':
                array_index = 0;
                memset(data_array, 0, sizeof(data_array));
                // APP_ERROR_CHECK(err_code);
                // NRF_LOG_INFO("BLE_OFF\n");
                if ((sent == 67) || (sent == 82))
                {
                    sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
                }
                else
                    sd_ble_gap_adv_stop(m_advertising.adv_handle);
                break;
            }
        }

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

/**@brief  Function for initializing the UART module.
 */
/**@snippet [UART Initialization] */
static void uart_init(void)
{
    // NRF_LOG_INFO("uart_init..\n");
    uint32_t err_code;
    app_uart_comm_params_t const comm_params =
    {
        UART_APP_RX,
        UART_APP_TX,
        0,
        0,
        APP_UART_FLOW_CONTROL_DISABLED,
        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_HIGH,err_code);
    // APP_UART_INIT(&comm_params,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)
{
    // NRF_LOG_INFO("advertising_init..\n");
    uint32_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 = false;
    init.advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_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 the nrf log module.
 */
static void log_init(void)
{
    // NRF_LOG_INFO("LOG init..\n");
    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)
{
    // NRF_LOG_INFO("PWR_MAN init.\n");
    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)
// {
//     // nrf_gpio_pin_toggle(LED_BLINK)
//     uint32_t err_code = ble_advertising_start(&m_advertising, BLE_ADV_MODE_FAST);
//     APP_ERROR_CHECK(err_code);
// }

/**@brief Application main function.
 */
int main(void)
{
    uart_init();
    log_init();
    SEGGER_RTT_Init();
    timers_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();
    app_timer_create(&m_TRAIL_timer_id, APP_TIMER_MODE_REPEATED, timeout_handler);
    app_timer_start(m_TRAIL_timer_id, TRAIL_TIMER, NULL);
    // nrf_gpio_cfg_output(LED_BLINK);

    // Start execution.

    NRF_LOG_INFO("Debug logging for UART over RTT started.");

    // advertising_start();
    for (;;)
    {
        idle_state_handle();
        if(uartrxrdyflag == true)
        {
             AppUartHandler();
        }
         if (overflowflag == true)
        {
            sequence += 1;
            overflowflag = false;

            err_code = ble_nus_data_send(&m_nus, Ble_array_to_apk, &length, m_conn_handle);
            // if(err_code == NRF_SUCCESS)
            // {

            // }
            memset(Ble_array_to_apk, 0, sizeof(Ble_array_to_apk));
            NRF_LOG_INFO("err_code: %d,sequence: %d\n", err_code, sequence);
        }
    }
}

static void timeout_handler(void *p_context)
{
    // NRF_LOG_INFO("sent :%d\n",sent);
    UNUSED_PARAMETER(p_context);
    // NRF_LOG_INFO("trail started..\n");
    app_uart_put(sent);
}
/**
 * @}
 */

In this way i trasmit 240 bytes every 10ms there will be loss happens.

How can i rectify this 

[Karl Ylvisaker]

Hello,

manobala12 said:

In this way i trasmit 240 bytes every 10ms there will be loss happens.

Please be as specific as possible when you are writing about the issue.
Do you mean that this code aims to send 240 bytes over BLE each second, but you are seeing the same kind of issue as you have described and illustrated with your logs earlier?

Looking through your code it seems to me that you are trying to implement something very similar to the functionality in the unmodified BLE NUS peripheral example - could elaborate on how you would like to change the functionality of the original example?

In your case you are for instance not checking the returned error code for the app_uart_get function, which if it fails will cause the remaining of your AppUartHandler to fail.
I think your issue lies in the AppUartHandler in this case. Is your intention to just check the received UART data for some specific bytes (local commands, such as N and L), and then to also send this same data over BLE to another device? If so, have you ensured that this data never will contain the 'command symbols'?

Please elaborate on the functionality you are trying to achieve here, so that I may best advice you on how to approach this.

Best regards,
Karl

[manobala12]

Hi karl

i got solution now there is no data loss 

I changed min and max_conn_interval to 10

But 1MB data transmitting time 1min36sec it takes how can i reduce it

[Karl Ylvisaker]

Hello,

manobala12 said:

i got solution now there is no data loss 

Great, I am glad to read that! :) 

manobala12 said:

I changed min and max_conn_interval to 10

But 1MB data transmitting time 1min36sec it takes how can i reduce it

To analyze where the bottleneck in your throughput is it would be helpful if you could capture a sniffer trace of the communication between the devices. Are you familiar with the nRF Sniffer tool?

Best regards,
Karl