Problem in data transfer in Bluetooth at 10ms

[sharmelaraju]

Hi,

We are using NRF52840 Dk board to transfer the data at 10ms through Bluetooth which is central and peripheral  as other cc250moda controller  Bluetooth. Our objective is to send the data of 8 bytes at  10ms from the NRF52840 Bluetooth to other Bluetooth. We are able to send the data from NRF52840 Bluetooth of 8 bytes at 30ms,50ms,100ms,500 ms to other controller Bluetooth correctly which means at every 50ms  we are sending 8  of bytes data which is receiving  8 bytes of data at every 50ms in the receiving controller Bluetooth. The problem here is when we are sending the  8 bytes of data at 10ms from NRF52840  Bluetooth to  receiving Bluetooth it should read  8 bytes of data at 10ms but here the problem is it is reading as 8 bytes, 16 bytes ,24 bytes ,0 bytes ,0 bytes, 24 bytes,16 bytes, 0 bytes, 0 bytes  as such at every 10 ms.Can you please tell me what is the problem . How to resolve the issue.

[Karl Ylvisaker]

Hello,

I am not sure I understand exactly what you issue is here, other than the BLE communication not behaving as wanted.
Could you detail the issue some more, what parameter are you changing to differentiate between the different sending intervals? Could you share that snippet of your code?

Best regards,
Karl

[sharmelaraju]

Thanks for the reply.

I am here by attaching the code here at 10 ms.

/**
 * Copyright (c) 2014 - 2019, 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.
 *
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 *
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
/**
 * @brief BLE LED Button Service central and client application main file.
 *
 * This file contains the source code for a sample client application using the LED Button service.
 */

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "nrf_sdh_soc.h"
#include "nrf_pwr_mgmt.h"
#include "app_timer.h"
#include "boards.h"
#include "bsp.h"
#include "bsp_btn_ble.h"
#include "ble.h"
#include "ble_hci.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "ble_db_discovery.h"
#include "ble_lbs_c.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_scan.h"

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



typedef unsigned char Byte_t;                   /* Generic 8 bit Container.   */



#define CENTRAL_SCANNING_LED            BSP_BOARD_LED_0                     /**< Scanning LED will be on when the device is scanning. */
#define CENTRAL_CONNECTED_LED           BSP_BOARD_LED_1                     /**< Connected LED will be on when the device is connected. */
#define LEDBUTTON_LED                   BSP_BOARD_LED_2                     /**< LED to indicate a change of state of the the Button characteristic on the peer. */

#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_DURATION                   0x0000                              /**< Timout when scanning. 0x0000 disables timeout. */

#define MIN_CONNECTION_INTERVAL         MSEC_TO_UNITS(7.5, UNIT_1_25_MS)    /**< Determines minimum connection interval in milliseconds. */
#define MAX_CONNECTION_INTERVAL         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             MSEC_TO_UNITS(4000, UNIT_10_MS)     /**< Determines supervision time-out in units of 10 milliseconds. */

#define LEDBUTTON_BUTTON_PIN            BSP_BUTTON_0                        /**< Button that will write to the LED characteristic of the peer */
#define BUTTON_DETECTION_DELAY          APP_TIMER_TICKS(50)                 /**< Delay from a GPIOTE event until a button is reported as pushed (in number of timer ticks). */

#define APP_BLE_CONN_CFG_TAG            1                                   /**< A tag identifying the SoftDevice BLE configuration. */
#define APP_BLE_OBSERVER_PRIO           3                                   /**< Application's BLE observer priority. You shouldn't need to modify this value. */

NRF_BLE_SCAN_DEF(m_scan);                                       /**< Scanning module instance. */
BLE_LBS_C_DEF(m_ble_lbs_c);                                     /**< Main structure used by the LBS client module. */
NRF_BLE_GATT_DEF(m_gatt);                                       /**< GATT module instance. */
BLE_DB_DISCOVERY_DEF(m_db_disc);                                /**< DB discovery module instance. */
#define BLE_NUS_MAX_DATA_LEN            8

//static char const m_target_periph_name[] = "Nordic_Blinky";     /**< Name of the device we try to connect to. This name is searched in the scan report data*/

static char const m_target_periph_name[] = "DEVICE";     /**< Name of the device we try to connect to. This name is searched in the scan report data*/

#define BATTERY_LEVEL_MEAS_INTERVAL         APP_TIMER_TICKS(10)                   /**< Battery level measurement interval (ticks). */

APP_TIMER_DEF(m_battery_timer_id);  

/**@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 the LEDs initialization.
 *
 * @details Initializes all LEDs used by the application.
 */
static void leds_init(void)
{
    bsp_board_init(BSP_INIT_LEDS);
}


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

    err_code = nrf_ble_scan_start(&m_scan);
    APP_ERROR_CHECK(err_code);

    bsp_board_led_off(CENTRAL_CONNECTED_LED);
    bsp_board_led_on(CENTRAL_SCANNING_LED);
}


/**@brief Handles events coming from the LED Button central module.
 */
static void lbs_c_evt_handler(ble_lbs_c_t * p_lbs_c, ble_lbs_c_evt_t * p_lbs_c_evt)
{
    switch (p_lbs_c_evt->evt_type)
    {
        case BLE_LBS_C_EVT_DISCOVERY_COMPLETE:
        {
            ret_code_t err_code;

            err_code = ble_lbs_c_handles_assign(&m_ble_lbs_c,
                                                p_lbs_c_evt->conn_handle,
                                                &p_lbs_c_evt->params.peer_db);
            NRF_LOG_INFO("LED Button service discovered on conn_handle 0x%x.", p_lbs_c_evt->conn_handle);

            err_code = app_button_enable();
            APP_ERROR_CHECK(err_code);

            // LED Button service discovered. Enable notification of Button.
            err_code = ble_lbs_c_button_notif_enable(p_lbs_c);
            APP_ERROR_CHECK(err_code);
        } break; // BLE_LBS_C_EVT_DISCOVERY_COMPLETE

        case BLE_LBS_C_EVT_BUTTON_NOTIFICATION:
        {
            NRF_LOG_INFO("Button state changed on peer to 0x%x.", p_lbs_c_evt->params.button.button_state);
            if (p_lbs_c_evt->params.button.button_state)
            {
                bsp_board_led_on(LEDBUTTON_LED);
            }
            else
            {
                bsp_board_led_off(LEDBUTTON_LED);
            }
        } break; // BLE_LBS_C_EVT_BUTTON_NOTIFICATION

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

void send_ble_data(uint8_t * p_data, uint16_t length)
{
static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
memcpy(data_array, p_data, length);
ble_nus_c_string_send(&m_ble_lbs_c, data_array, length);
}
/**@brief Function for handling the Battery measurement timer timeout.
 *
 * @details This function will be called each time the battery level measurement timer expires.
 *
 * @param[in] p_context  Pointer used for passing some arbitrary information (context) from the
 *                       app_start_timer() call to the timeout handler.
 */
static void battery_level_meas_timeout_handler(void * p_context)
{
    UNUSED_PARAMETER(p_context);
    

	uint8_t var=0;
	static int seq=0;
	Byte_t dummyData[8];		// the data packet.
//	static int seq;
//	int crc=0,crc1=0;					//WARNING----- DO NOT INTERCHANGE THIS AND BELOW THIS ONE. IF IT IS NOT IN THIS ORDER, YOU WILL
//	uint8_t crc_i=0;					// GET ERROR IN ANDROID SIDE OF CRC. LET THIS AND ABOVE THIS, BE LIKE THIS ONLY.
	//11-4-18--11:30am--- i think dat error is coz i didnt initialize crc to 0. now i did and crc error gone. so, maybe you can
	// ignore the warning. Anyway, I won't change those things as I dont want to take risk. Upto you to decide what you wanna do.

	//int crc,crc1=0; changed to int from int16_t(or somethign, refer in my main codes v2.10 or something). now crc error stopped.
	//13-3-18-- crc error was getting after doing service mode. so, did this above change now to stop the error.



	//--------------------------------------forming data packet-----------------------------------


	for(var=0;var<=8;var++) 			// to form 6 byte data-packet format
	{
		switch(var)
		{
			case 0:							//indication bit whther it's data or command.

				dummyData[var]=0x12; 				// 0 indicates, it's data ( for command=1)
				break;


			case 1:							//for ibp middle. ignore ibp MSB

				dummyData[var]=0x13;
				break;

			case 2:							//ibp LSB

				dummyData[var]=0x15;
				break;

			case 3:							//for ibp middle. ignore ibp MSB

			    dummyData[var]=0x16;
				break;


			case 4:										// for  sequence numbers

				dummyData[var]=0x18;
					break;
				
		 case 5:										// for  sequence numbers

				dummyData[var]=0x17;
				break;

			case 6:										// for  sequence numbers

				dummyData[var]=0x11;
				break;

			case 7:										// for  sequence numbers

				dummyData[var]=seq;
				seq++; // it will go from 0 to 124
				if(seq==20)
				{
					seq=0;
				}
				break;
			}
		}
	
send_ble_data(dummyData, sizeof(dummyData));
	
}


/**@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)
{
    ret_code_t err_code;

    // For readability.
    ble_gap_evt_t const * p_gap_evt = &p_ble_evt->evt.gap_evt;

    switch (p_ble_evt->header.evt_id)
    {
        // Upon connection, check which peripheral has connected (HR or RSC), initiate DB
        // discovery, update LEDs status and resume scanning if necessary. */
        case BLE_GAP_EVT_CONNECTED:
        {
            NRF_LOG_INFO("Connected.\r\n");
            err_code = ble_lbs_c_handles_assign(&m_ble_lbs_c, p_gap_evt->conn_handle, NULL);
            APP_ERROR_CHECK(err_code);

            err_code = ble_db_discovery_start(&m_db_disc, p_gap_evt->conn_handle);
            APP_ERROR_CHECK(err_code);
					  if(err_code==NRF_SUCCESS)
						{
							NRF_LOG_INFO("DISCOVERY COMPLETED\r\n");
            
						}

            // Update LEDs status, and check if we should be looking for more
            // peripherals to connect to.
            bsp_board_led_on(CENTRAL_CONNECTED_LED);
            bsp_board_led_off(CENTRAL_SCANNING_LED);
        } break;

        // Upon disconnection, reset the connection handle of the peer which disconnected, update
        // the LEDs status and start scanning again.
        case BLE_GAP_EVT_DISCONNECTED:
        {
            NRF_LOG_INFO("Disconnected.");
            scan_start();
        } break;

        case BLE_GAP_EVT_TIMEOUT:
        {
            // We have not specified a timeout for scanning, so only connection attemps can timeout.
            if (p_gap_evt->params.timeout.src == BLE_GAP_TIMEOUT_SRC_CONN)
            {
                NRF_LOG_INFO("Connection request timed out.");
            }
        } break;

        case BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
        {
            // Accept 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;

        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_INFO("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_GATTC_EVT_TIMEOUT:
        {
            // Disconnect on GATT Client timeout event.
            NRF_LOG_INFO("GATT Client Timeout.");
            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.
            NRF_LOG_INFO("GATT Server Timeout.");
            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_SYS_ATTR_MISSING:
            // No system attributes have been stored.
            err_code = sd_ble_gatts_sys_attr_set(p_ble_evt->evt.gatts_evt.conn_handle, NULL, 0, 0);
            APP_ERROR_CHECK(err_code);
        default:
            // No implementation needed.
            break;
    }
}

/**@brief Function for starting application timers.
 */
static void application_timers_start(void)
{
    ret_code_t err_code;

    // Start application timers.
    err_code = app_timer_start(m_battery_timer_id, BATTERY_LEVEL_MEAS_INTERVAL, NULL);
    APP_ERROR_CHECK(err_code);
}

/**@brief LED Button client initialization.
 */
static void lbs_c_init(void)
{
    ret_code_t       err_code;
    ble_lbs_c_init_t lbs_c_init_obj;

    lbs_c_init_obj.evt_handler = lbs_c_evt_handler;

    err_code = ble_lbs_c_init(&m_ble_lbs_c, &lbs_c_init_obj);
    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 handling events from the button handler module.
 *
 * @param[in] pin_no        The pin that the event applies to.
 * @param[in] button_action The button action (press/release).
 */
static void button_event_handler(uint8_t pin_no, uint8_t button_action)
{
    ret_code_t err_code;

    switch (pin_no)
    {
        case LEDBUTTON_BUTTON_PIN:
            err_code = ble_lbs_led_status_send(&m_ble_lbs_c, button_action);
            if (err_code != NRF_SUCCESS &&
                err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
                err_code != NRF_ERROR_INVALID_STATE)
            {
                APP_ERROR_CHECK(err_code);
            }
            if (err_code == NRF_SUCCESS)
            {
                NRF_LOG_INFO("LBS write LED state %d", button_action);
            }
            break;

        default:
            APP_ERROR_HANDLER(pin_no);
            break;
    }
}


/**@brief Function for handling Scaning events.
 *
 * @param[in]   p_scan_evt   Scanning event.
 */
static void scan_evt_handler(scan_evt_t const * p_scan_evt)
{
    ret_code_t err_code;

    switch(p_scan_evt->scan_evt_id)
    {
        case NRF_BLE_SCAN_EVT_CONNECTING_ERROR:
            err_code = p_scan_evt->params.connecting_err.err_code;
            APP_ERROR_CHECK(err_code);
            break;
        default:
          break;
    }
}



/**@brief Function for initializing the button handler module.
 */
static void buttons_init(void)
{
    ret_code_t err_code;

    //The array must be static because a pointer to it will be saved in the button handler module.
    static app_button_cfg_t buttons[] =
    {
        {LEDBUTTON_BUTTON_PIN, false, BUTTON_PULL, button_event_handler}
    };

    err_code = app_button_init(buttons, ARRAY_SIZE(buttons),
                               BUTTON_DETECTION_DELAY);
    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_lbs_on_db_disc_evt(&m_ble_lbs_c, p_evt);
}


/**@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 initializing the log.
 */
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);
	 err_code = app_timer_create(&m_battery_timer_id,
                                APP_TIMER_MODE_REPEATED,
                                battery_level_meas_timeout_handler);
    APP_ERROR_CHECK(err_code);

}


/**@brief Function for initializing the Power manager. */
static void power_management_init(void)
{
    ret_code_t err_code;
    err_code = nrf_pwr_mgmt_init();
    APP_ERROR_CHECK(err_code);
}


static void scan_init(void)
{
    ret_code_t          err_code;
    nrf_ble_scan_init_t init_scan;

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

    init_scan.connect_if_match = true;
    init_scan.conn_cfg_tag     = APP_BLE_CONN_CFG_TAG;

    err_code = nrf_ble_scan_init(&m_scan, &init_scan, scan_evt_handler);
    APP_ERROR_CHECK(err_code);

    // Setting filters for scanning.
    err_code = nrf_ble_scan_filters_enable(&m_scan, NRF_BLE_SCAN_NAME_FILTER, false);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filter_set(&m_scan, SCAN_NAME_FILTER, m_target_periph_name);
    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 the idle state (main loop).
 *
 * @details Handle any pending log operation(s), then sleep until the next event occurs.
 */
static void idle_state_handle(void)
{
    NRF_LOG_FLUSH();
    nrf_pwr_mgmt_run();
}


int main(void)
{
    // Initialize.
    log_init();
    timer_init();
    leds_init();
    buttons_init();
    power_management_init();
    ble_stack_init();
    scan_init();
    gatt_init();
    db_discovery_init();
    lbs_c_init();

    // Start execution.
    NRF_LOG_INFO("Blinky CENTRAL example started.");
    scan_start();

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

    // Enter main loop.
    for (;;)
    {
        idle_state_handle();
    }
}

please give me the solution.

[sharmelaraju]

Hi,

I am here by attaching the code.

/**
 * Copyright (c) 2014 - 2019, 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.
 *
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 *
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
/**
 * @brief BLE LED Button Service central and client application main file.
 *
 * This file contains the source code for a sample client application using the LED Button service.
 */

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "nrf_sdh_soc.h"
#include "nrf_pwr_mgmt.h"
#include "app_timer.h"
#include "boards.h"
#include "bsp.h"
#include "bsp_btn_ble.h"
#include "ble.h"
#include "ble_hci.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "ble_db_discovery.h"
#include "ble_lbs_c.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_scan.h"

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



typedef unsigned char Byte_t;                   /* Generic 8 bit Container.   */



#define CENTRAL_SCANNING_LED            BSP_BOARD_LED_0                     /**< Scanning LED will be on when the device is scanning. */
#define CENTRAL_CONNECTED_LED           BSP_BOARD_LED_1                     /**< Connected LED will be on when the device is connected. */
#define LEDBUTTON_LED                   BSP_BOARD_LED_2                     /**< LED to indicate a change of state of the the Button characteristic on the peer. */

#define SCAN_INTERVAL                   0x0030                              /**< Determines scan interval in units of 0.625 millisecond. */
#define SCAN_WINDOW                     0x0030                              /**< Determines scan window in units of 0.625 millisecond. */
#define SCAN_DURATION                   0x0000                              /**< Timout when scanning. 0x0000 disables timeout. */

#define MIN_CONNECTION_INTERVAL         MSEC_TO_UNITS(20, UNIT_1_25_MS)    /**< Determines minimum connection interval in milliseconds. */
#define MAX_CONNECTION_INTERVAL         MSEC_TO_UNITS(20, 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             MSEC_TO_UNITS(4000, UNIT_10_MS)     /**< Determines supervision time-out in units of 10 milliseconds. */

#define LEDBUTTON_BUTTON_PIN            BSP_BUTTON_0                        /**< Button that will write to the LED characteristic of the peer */
#define BUTTON_DETECTION_DELAY          APP_TIMER_TICKS(50)                 /**< Delay from a GPIOTE event until a button is reported as pushed (in number of timer ticks). */

#define APP_BLE_CONN_CFG_TAG            1                                   /**< A tag identifying the SoftDevice BLE configuration. */
#define APP_BLE_OBSERVER_PRIO           3                                   /**< Application's BLE observer priority. You shouldn't need to modify this value. */

NRF_BLE_SCAN_DEF(m_scan);                                       /**< Scanning module instance. */
BLE_LBS_C_DEF(m_ble_lbs_c);                                     /**< Main structure used by the LBS client module. */
NRF_BLE_GATT_DEF(m_gatt);                                       /**< GATT module instance. */
BLE_DB_DISCOVERY_DEF(m_db_disc);                                /**< DB discovery module instance. */
#define BLE_NUS_MAX_DATA_LEN            8

//static char const m_target_periph_name[] = "Nordic_Blinky";     /**< Name of the device we try to connect to. This name is searched in the scan report data*/

static char const m_target_periph_name[] = "DEVICE";     /**< Name of the device we try to connect to. This name is searched in the scan report data*/

#define BATTERY_LEVEL_MEAS_INTERVAL         APP_TIMER_TICKS(20)                   /**< Battery level measurement interval (ticks). */

APP_TIMER_DEF(m_battery_timer_id);  

/**@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 the LEDs initialization.
 *
 * @details Initializes all LEDs used by the application.
 */
static void leds_init(void)
{
    bsp_board_init(BSP_INIT_LEDS);
}


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

    err_code = nrf_ble_scan_start(&m_scan);
    APP_ERROR_CHECK(err_code);

    bsp_board_led_off(CENTRAL_CONNECTED_LED);
    bsp_board_led_on(CENTRAL_SCANNING_LED);
}


/**@brief Handles events coming from the LED Button central module.
 */
static void lbs_c_evt_handler(ble_lbs_c_t * p_lbs_c, ble_lbs_c_evt_t * p_lbs_c_evt)
{
    switch (p_lbs_c_evt->evt_type)
    {
        case BLE_LBS_C_EVT_DISCOVERY_COMPLETE:
        {
            ret_code_t err_code;

            err_code = ble_lbs_c_handles_assign(&m_ble_lbs_c,
                                                p_lbs_c_evt->conn_handle,
                                                &p_lbs_c_evt->params.peer_db);
            NRF_LOG_INFO("LED Button service discovered on conn_handle 0x%x.", p_lbs_c_evt->conn_handle);

            err_code = app_button_enable();
            APP_ERROR_CHECK(err_code);

            // LED Button service discovered. Enable notification of Button.
            err_code = ble_lbs_c_button_notif_enable(p_lbs_c);
            APP_ERROR_CHECK(err_code);
        } break; // BLE_LBS_C_EVT_DISCOVERY_COMPLETE

       /* case BLE_LBS_C_EVT_BUTTON_NOTIFICATION:
        {
            NRF_LOG_INFO("Button state changed on peer to 0x%x.", p_lbs_c_evt->params.button.button_state);
            if (p_lbs_c_evt->params.button.button_state)
            {
                bsp_board_led_on(LEDBUTTON_LED);
            }
            else
            {
                bsp_board_led_off(LEDBUTTON_LED);
            }
        } break; // BLE_LBS_C_EVT_BUTTON_NOTIFICATION*/

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

void send_ble_data(uint8_t * p_data, uint16_t length)
{
	uint32_t  err_code;
static uint8_t data_array[BLE_NUS_MAX_DATA_LEN];
memcpy(data_array, p_data, length);
ble_nus_c_string_send(&m_ble_lbs_c, data_array, length);
}
	
/**@brief Function for handling the Battery measurement timer timeout.
 *
 * @details This function will be called each time the battery level measurement timer expires.
 *
 * @param[in] p_context  Pointer used for passing some arbitrary information (context) from the
 *                       app_start_timer() call to the timeout handler.
 */
static void battery_level_meas_timeout_handler()
{
   // UNUSED_PARAMETER(p_context);
    //battery_level_update();
	
uint8_t dummyData[8] ;

int i=0;	

//nrf_gpio_pin_toggle(24);
	
dummyData[0]=0X11;
	
dummyData[1]=0X12;

dummyData[2]=0X23;
	
dummyData[3]=0X34;

dummyData[4]=0X55;
	
dummyData[5]=0X66;

dummyData[6]=0X57;
	
dummyData[7]=0x58;
send_ble_data(dummyData, sizeof(dummyData));
	
}


/**@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)
{
    ret_code_t err_code;

    // For readability.
    ble_gap_evt_t const * p_gap_evt = &p_ble_evt->evt.gap_evt;

    switch (p_ble_evt->header.evt_id)
    {
        // Upon connection, check which peripheral has connected (HR or RSC), initiate DB
        // discovery, update LEDs status and resume scanning if necessary. */
        case BLE_GAP_EVT_CONNECTED:
        {
            NRF_LOG_INFO("Connected.\r\n");
					   nrf_ble_scan_stop();
        
            err_code = ble_lbs_c_handles_assign(&m_ble_lbs_c, p_gap_evt->conn_handle, NULL);
            APP_ERROR_CHECK(err_code);

            err_code = ble_db_discovery_start(&m_db_disc, p_gap_evt->conn_handle);
            APP_ERROR_CHECK(err_code);
					  if(err_code==NRF_SUCCESS)
						{
							NRF_LOG_INFO("DISCOVERY COMPLETED\r\n");
            
						}

            // Update LEDs status, and check if we should be looking for more
            // peripherals to connect to.
            bsp_board_led_on(CENTRAL_CONNECTED_LED);
            bsp_board_led_off(CENTRAL_SCANNING_LED);
						} break;

        // Upon disconnection, reset the connection handle of the peer which disconnected, update
        // the LEDs status and start scanning again.
        case BLE_GAP_EVT_DISCONNECTED:
        {
            NRF_LOG_INFO("Disconnected.");
            scan_start();
        } break;

        case BLE_GAP_EVT_TIMEOUT:
        {
            // We have not specified a timeout for scanning, so only connection attemps can timeout.
            if (p_gap_evt->params.timeout.src == BLE_GAP_TIMEOUT_SRC_CONN)
            {
                NRF_LOG_INFO("Connection request timed out.");
            }
        } break;

        case BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
        {
            // Accept 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;

        case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
        {
            NRF_LOG_INFO("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_GATTC_EVT_TIMEOUT:
        {
            // Disconnect on GATT Client timeout event.
            NRF_LOG_INFO("GATT Client Timeout.");
            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.
            NRF_LOG_INFO("GATT Server Timeout.");
            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_SYS_ATTR_MISSING:
            // No system attributes have been stored.
            err_code = sd_ble_gatts_sys_attr_set(p_ble_evt->evt.gatts_evt.conn_handle, NULL, 0, 0);
            APP_ERROR_CHECK(err_code);
        default:
            // No implementation needed.
            break;
				
    }
}

/**@brief Function for starting application timers.
 */
static void application_timers_start(void)
{
    ret_code_t err_code;

    // Start application timers.
    err_code = app_timer_start(m_battery_timer_id, BATTERY_LEVEL_MEAS_INTERVAL, NULL);
    APP_ERROR_CHECK(err_code);
}

/**@brief LED Button client initialization.
 */
static void lbs_c_init(void)
{
    ret_code_t       err_code;
    ble_lbs_c_init_t lbs_c_init_obj;

    lbs_c_init_obj.evt_handler = lbs_c_evt_handler;

    err_code = ble_lbs_c_init(&m_ble_lbs_c, &lbs_c_init_obj);
    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 handling events from the button handler module.
 *
 * @param[in] pin_no        The pin that the event applies to.
 * @param[in] button_action The button action (press/release).
 */
/*static void button_event_handler(uint8_t pin_no, uint8_t button_action)
{
    ret_code_t err_code;

    switch (pin_no)
    {
        case LEDBUTTON_BUTTON_PIN:
            err_code = ble_lbs_led_status_send(&m_ble_lbs_c, button_action);
            if (err_code != NRF_SUCCESS &&
                err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
                err_code != NRF_ERROR_INVALID_STATE)
            {
                APP_ERROR_CHECK(err_code);
            }
            if (err_code == NRF_SUCCESS)
            {
                NRF_LOG_INFO("LBS write LED state %d", button_action);
            }
            break;

        default:
            APP_ERROR_HANDLER(pin_no);
            break;
    }
}
*/

/**@brief Function for handling Scaning events.
 *
 * @param[in]   p_scan_evt   Scanning event.
 */
static void scan_evt_handler(scan_evt_t const * p_scan_evt)
{
    ret_code_t err_code;

    switch(p_scan_evt->scan_evt_id)
    {
        case NRF_BLE_SCAN_EVT_CONNECTING_ERROR:
            err_code = p_scan_evt->params.connecting_err.err_code;
            APP_ERROR_CHECK(err_code);
            break;
        default:
          break;
    }
}



/**@brief Function for initializing the button handler module.
 */
/*static void buttons_init(void)
{
    ret_code_t err_code;

    //The array must be static because a pointer to it will be saved in the button handler module.
    static app_button_cfg_t buttons[] =
    {
        {LEDBUTTON_BUTTON_PIN, false, BUTTON_PULL, button_event_handler}
    };

    err_code = app_button_init(buttons, ARRAY_SIZE(buttons),
                               BUTTON_DETECTION_DELAY);
    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_lbs_on_db_disc_evt(&m_ble_lbs_c, p_evt);
}


/**@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 initializing the log.
 */
static void log_init(void)
{
    ret_code_t err_code = NRF_LOG_INIT(get_rtc_counter);
    APP_ERROR_CHECK(err_code);

    NRF_LOG_DEFAULT_BACKENDS_INIT();
}
uint32_t  get_rtc_counter(void)
{
	return NRF_RTC1->COUNTER;
}


/**@brief Function for initializing the timer.
 */
static void timer_init(void)
{
    ret_code_t err_code = app_timer_init();
    APP_ERROR_CHECK(err_code);
	 err_code = app_timer_create(&m_battery_timer_id,
                                APP_TIMER_MODE_REPEATED,
                                battery_level_meas_timeout_handler);
    APP_ERROR_CHECK(err_code);

}


/**@brief Function for initializing the Power manager. */
static void power_management_init(void)
{
    ret_code_t err_code;
    err_code = nrf_pwr_mgmt_init();
    APP_ERROR_CHECK(err_code);
}


static void scan_init(void)
{
    ret_code_t          err_code;
    nrf_ble_scan_init_t init_scan;

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

    init_scan.connect_if_match = true;
    init_scan.conn_cfg_tag     = APP_BLE_CONN_CFG_TAG;

    err_code = nrf_ble_scan_init(&m_scan, &init_scan, scan_evt_handler);
    APP_ERROR_CHECK(err_code);

    // Setting filters for scanning.
    err_code = nrf_ble_scan_filters_enable(&m_scan, NRF_BLE_SCAN_NAME_FILTER, false);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filter_set(&m_scan, SCAN_NAME_FILTER, m_target_periph_name);
    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 the idle state (main loop).
 *
 * @details Handle any pending log operation(s), then sleep until the next event occurs.
 */
static void idle_state_handle(void)
{
    NRF_LOG_FLUSH();
    nrf_pwr_mgmt_run();
}



int main(void)
{
    // Initialize.
    log_init();
    timer_init();
    leds_init();
   // buttons_init();
    power_management_init();
    ble_stack_init();
    scan_init();
    gatt_init();
    db_discovery_init();
    lbs_c_init();

    // Start execution.
    NRF_LOG_INFO("Blinky CENTRAL example started.");
    scan_start();

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

    // Enter main loop.
    for (;;)
    {
        idle_state_handle();
    }
}

Please give me the solution

[Karl Ylvisaker]

Hello again,

This is just the contents of your main.c source code file - if I am to be able to run your code on my end, I will need the entire project directory, complete with the project and configuration files as well. If you would like to send me this, please compress the project folder to a .zip or .7z file, and post it here, so I may take a look.
Before you do this, please make sure that the project you are sending is the correct version, exhibiting the behavior you have detailed earlier.

Best regards,
Karl

[sharmelaraju]

Thanks for the reply.

I am here by sharing the entire project  in the folder IBP_DONGLE( NRF52840), Soft device s 140,   SDK VERSION 15.3, EXAMPLE -ble_app_blinky.IBP_DONGLE.rar

[Karl Ylvisaker]

Thank you for you patience.
I have allocated time to review your code tomorrow.

I'll get back to you once I have looked over the code.

Best regards,
Karl

[Karl Ylvisaker]

Hi again,

I have been able to replicate your minimal 20 ms connection interval with the code you provided.
I have also successfully created a modified version of the Blinky examples, that communicate with 10 ms connection intervals - since this is the basis of your application.

Tomorrow I will pursue the reason for your application only achieving to send every 20 ms.

Best regards,
Karl

[sharmelaraju]

Thanks for the support.

In our application  we need to achieve at every 10ms. 

[Karl Ylvisaker]

Hello,

sharmelaraju said:

Thanks for the support.

No problem at all, I am happy to help!

sharmelaraju said:

In our application  we need to achieve at every 10ms. 

Yes, that much is understood.
I took a closer look at the code you provided, and made some discoveries.
First of all, the reason why you have not been able to set the connection interval properly: It seems that there is a bug in the ble_central/blinky source code, where it in fact does not make use of the parameters MIN_CONNECTION_INTERVAL and MAX_CONNECTION_INTERVAL as specified in main.c - but instead uses the default NRF_BLE_SCAN_MIN_CONNECTION_INTERVAL from the sdk_config.h file.
I have created an internal ticket on these misleading lines, for our SDK team to take a closer look at. I am sorry for any confusion this has caused you in your development.

Having found this, I changed the NRF_BLE_SCAN_MIN_CONNECTION_INTERVAL and NRF_BLE_SCAN_MAX_CONNECTION_INTERVAL to 10, which resulted in the expected 10 ms connection interval between the central device and an arbitrary peripheral device I set up.

Then, I used a Sniffer tool to capture the BLE traffic from the central, and noticed that it was only sending the data every other connection interval, instead of every 10 ms.
Taking a closer look at you code, I see that you have merged the Led Button service with the Nordic UART example service, and discovered that your data is scheduled to be sent every 20 ms by your "battery_level_meas_timeour_handler()" function. I changed the BATTERY_LEVEL_MEAS_INTERVAL from 20 ms to 10 ms, and observed that the changes were reflected in the BLE traffic captured using the Sniffer. I have attached the sniffer log here, for you to take a look at.

For future reference, I strongly recommend changing variable- and function-names so that they match their actual function, for significantly increased readability.

You can find the changes I made to your project code by looking at the lines preceded by "CHANGE START" and ending with "CHANGE END"
I recommend that you take a look at the changes I have made, but input them into your project yourself - rather than continuing to develop using the code I have sent.
This will ensure that you have full control and understanding of the changes made.

Please let me know if you should encounter any other questions or issues in the future.

Best regards,
Karl

sharmelaraju.pcapngIBP_DONGLE.zip

[sharmelaraju]

Thanks for the support.

I have tried your it is working....I am receiving the 8 bytes of data at every 10 ms .But sometimes the receiver Bluetooth reads 24 bytes,16 bytes,0 bytes. Can you please tell me how to resolve this issue.

I am here by attaching the log of the received data.MAIN_IBP_DONGLE.txt

[Karl Ylvisaker]

No problem at all, I am happy to help!

I see.
Could you provide me with a sniffer trace of the BLE traffic you are seeing?
On my end, the central is communicating as expected, and I am not seeing these deviations.
With a sniffer trace, I would be able to pinpoint if the issue is with your central, peripheral or the BLE link.

What else, other than receiving BLE communication, is the peripheral doing?
Could you ensure that the peripheral always has enough time to process the received data?

Looking forward to resolving this issue,

Best regards,
Karl

[sharmelaraju]

Thanks for the reply.

sorry for the delayed response.

I am here by attaching the  sniffer log  central(NRF52840) and peripheral( CC2564MODA Bluetooth).

Plz give me the solution.LOG12.pcapngLOG22.pcapng