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.

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/**
 * @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]

Plz give me the solution.

[Karl Ylvisaker]

Hello again,

Those logs were much better, thank you.

When viewing the logs, this seems exactly as it should be to me.
The delta time for each transmission is ~10 ms for each transmission. From this, we can now be sure that you are in fact completing your data transmission (the 0x11, 0x12, 0x15 .. data) every 10 ms.
If you take a look at packet number 531 particularly, that is when the central initiates the connection - with 8 as connection interval, which translates to 10 ms (8 * 1.25 ms).

Seeing this, in combination with the printed UART log you shared earlier(where the data is not being processed right away after being received. So, that leads us to examining what the peripheral spends its time doing.

When does the data handling happen? Could it be that your device is over encumbered, and thus not always finish its processing of the received data in time, before a new packet is received?
It could also be that the UART logging itself is what pushes the peripheral to miss its processing windows - are you using deferred logging?

Best regards,
Karl

[sharmelaraju]

Thanks for the reply.

In the peripheral side the there is an scheduler function which reads the data at every 10ms. I am using termite application to log the data from the controller.

But in the captured_log1data i have noticed that one point of time the master has not connected to slave  but the data is sending.I am here by attaching the log file .

please give me the solution.

[Karl Ylvisaker]

Hello,

sharmelaraju said:

In the peripheral side the there is an scheduler function which reads the data at every 10ms. I am using termite application to log the data from the controller.

Could you share some code or elaborate more on the scheduler function you use to read data ever 10 ms? It could be that this scheduler does not work as intended.

sharmelaraju said:

But in the captured_log1data i have noticed that one point of time the master has not connected to slave  but the data is sending.I am here by attaching the log file .

The first highlighted section might be caused by the peripheral not acknowledging the reception of the packet sent from the central device. This causes the central to resend the packet. 
It might also be due to that the sniffer might receive packets that is lost or corrupted to the central/peripheral device - and vice verse. The first highlighted section of the screenshot you have shared might be showing this. That the sniffer lost a packet that the central/peripheral might still have received.
The frequency of loss and packet corruption depends heavily on the environment in which the devices are working.

What is interesting is the transmission starting on packet number 1209... I must have missed this exchange when reading the log earlier. What might be happening is that the central attempts to start a transfer, that is not acknowledged by the slave. This causes the central to have to wait until the next connection interval to re-transmit the non-acknowledged packet. Since your program schedules new data to be sent every 10 ms, a new packet will be placed in the TX buffer before the previous is retransmitted. This leads to the transmission exchanges we are seeing at packet 1209 - the master suddenly has more than one packet to transmitt at once, since the previous one was never acknowledged.
The re-transmission feature also ensures that no data is lost, even though it will arrive in the next connection interval. Note also how all the extra data is fitted into the next connection interval, without causing any sort of delay.
So, In essence; you are ensured that all the data will be transmitted over the BLE connection, but some data might arrive in the next connection interval, if the first transmission attempt is never acknowledged by the peripheral.
This is probably the cause of the logger "stutter" you've seen in your log. :)

As for the Empty PDU in the second highlighted section, it is probably caused by the central TX buffer being empty when the connection interval is up, causing the central to send an empty packet just to maintain the connection to the peripheral.
You can double click the packet in question  to see its contents.

Best regards,
Karl

[sharmelaraju]

Thanks.

I am hereby attaching the code of the peripheral which reads the data every 10ms.

Fullscreen per_code.txt Download

 /* The following function is the main user interface thread.  It     */
   /* opens the Bluetooth Stack and then drives the main user interface.*/


int main(void)
{
   /* Configure the hardware for its intended use.                      */
   HAL_ConfigureHardware(1);

   /* Enable interrupts and call the main application thread.           */
   MainThread();

   /* MainThread should run continously, if it exits an error occured.  */
   while(1)
   {
      ToggleLED(NULL);

      BTPS_Delay(100);
   }
}

   /* The following function is the main user interface thread.  It     */
   /* opens the Bluetooth Stack and then drives the main user interface.*/
static void MainThread(void)
{
   int                           Result;
   BTPS_Initialization_t         BTPS_Initialization;
   HCI_DriverInformation_t       HCI_DriverInformation;
   HCI_HCILLConfiguration_t      HCILLConfig;
   HCI_Driver_Reconfigure_Data_t DriverReconfigureData;

   /* Configure the UART Parameters.                                    */
   HCI_DRIVER_SET_COMM_INFORMATION(&HCI_DriverInformation, 1, VENDOR_BAUD_RATE, cpHCILL_RTS_CTS);
   HCI_DriverInformation.DriverInformation.COMMDriverInformation.InitializationDelay = 100;

   /* Set up the application callbacks.                                 */
   BTPS_Initialization.GetTickCountCallback  = GetTickCallback;
   BTPS_Initialization.MessageOutputCallback = DisplayCallback;

   /* Initialize the application.                                       */
   if((Result = InitializeApplication(&HCI_DriverInformation, &BTPS_Initialization)) > 0)
   {
      /* Register a sleep mode callback if we are using HCILL Mode.     */
      if((HCI_DriverInformation.DriverInformation.COMMDriverInformation.Protocol == cpHCILL) || (HCI_DriverInformation.DriverInformation.COMMDriverInformation.Protocol == cpHCILL_RTS_CTS))
      {
         HCILLConfig.SleepCallbackFunction        = HCI_Sleep_Callback;
         HCILLConfig.SleepCallbackParameter       = 0;
         DriverReconfigureData.ReconfigureCommand = HCI_COMM_DRIVER_RECONFIGURE_DATA_COMMAND_CHANGE_HCILL_PARAMETERS;
         DriverReconfigureData.ReconfigureData    = (void *)&HCILLConfig;

         /* Register the sleep mode callback.  Note that if this        */
         /* function returns greater than 0 then sleep is currently     */
         /* enabled.                                                    */
         Result = HCI_Reconfigure_Driver((unsigned int)Result, FALSE, &DriverReconfigureData);
         if(Result > 0)
         {
            /* Flag that sleep mode is enabled.                         */
            Display(("Sleep is allowed.\r\n"));
         }
      }

      /* We need to execute Add a function to process the command line  */
      /* to the BTPS Scheduler.                                         */
      if(BTPS_AddFunctionToScheduler(ReadFunction, NULL, 10))
      {
         /* Add the idle function (which determines if LPM3 may be      */
         /* entered) to the scheduler.                                  */
         if(BTPS_AddFunctionToScheduler( Writefunction, NULL, 10))
         {
            /* Loop forever and execute the scheduler.                  */
            while(1)
               BTPS_ExecuteScheduler();
         }
      }
   }
}
static void ReadFunction(void *UserParameter)
{
//xxx Fill in to put processor into low power mode
	ProcessCommandLine1();
}
static void Writefunction(void *UserParameter)
{
//xxx Fill in to put processor into low power mode
	ProcessCommandLine2();
}
void ProcessCommandLine1()
{
  //Display(("Read data\r\n"));
   ReadDataCommand(NULL);
}
void ProcessCommandLine2()
{
  //Display(("Write data\r\n"));
   SendDataCommand(NULL);
}

   /* The following function is responsible for reading data sent by a  */
   /* remote device to which a connection exists.  This function will   */
   /* return zero on successful execution and a negative value on       */
   /* errors.                                                           */

static int ReadDataCommand(ParameterList_t *TempParam)
{
   int           LEConnectionIndex;
   Boolean_t     Done;
   //  char BT_address[12] = "d78206cba936";
    //  char BT_address[12] = "f43538fe9c18";
   char BT_address[12] = "cc78ab7945c2";

   BD_ADDR_t     BD_ADDR;
   unsigned int  Temp;
   DeviceInfo_t *DeviceInfo;

   /* Next, make sure that a valid device address exists.               */
  // if((TempParam) && (TempParam->NumberofParameters > 0) && (TempParam->Params[0].strParam) && (BTPS_StringLength(TempParam->Params[0].strParam) >= (sizeof(BD_ADDR_t)*2)))
   //{
      /* Convert the parameter to a Bluetooth Device Address.           */
     // StrToBD_ADDR(TempParam->Params[0].strParam, &BD_ADDR);
      StrToBD_ADDR(BT_address, &BD_ADDR);

      /* Find the LE Connection Index for this connection.              */
      if((LEConnectionIndex = FindLEIndexByAddress(BD_ADDR)) >= 0)
      {
         /* Get the device info for the connection device.              */
         if((DeviceInfo = SearchDeviceInfoEntryByBD_ADDR(&DeviceInfoList, LEContextInfo[LEConnectionIndex].ConnectionBD_ADDR)) != NULL)
         {
            /* Determine the number of bytes we are going to read.      */
            Temp = LEContextInfo[LEConnectionIndex].SPPLEBufferInfo.ReceiveBuffer.BufferSize - LEContextInfo[LEConnectionIndex].SPPLEBufferInfo.ReceiveBuffer.BytesFree;

            Display(("Read: %u.\r\n", Temp));

            /* Loop and read all of the data.                           */
            Done = FALSE;
            while(!Done)
            {
               /* Read the data.                                        */
               Temp = SPPLEReadData(&(LEContextInfo[LEConnectionIndex]), DeviceInfo, SPPLE_DATA_BUFFER_LENGTH, SPPLEBuffer);
               if(Temp > 0)
               {
                  /* Display the data.                                  */
                  SPPLEBuffer[Temp] = '\0';
                  Display(((char *)SPPLEBuffer));
               }
               else
                  Done = TRUE;
            }
            Display(("\r\n"));
         }
         else
            Display(("No Device Info.\r\n"));
      }
      else
      {
         /* No matching ConnectionBD_ADDR.                              */
         Display(("No connection with BD_ADDR %s exists.\r\n", TempParam->Params[0].strParam));
      }
  // }
   //else
   //{
      /* Invalid parameters specified so flag an error to the user.     */
     // Display(("Usage: LEREAD [BD_ADDR].\r\n"));
   //}

   return(0);
}
  /* The following function is responsible for sending a number of     */
   /* characters to a remote device to which a connection exists.  The  */
   /* function receives a parameter that indicates the number of byte to*/
   /* be transferred.  This function will return zero on successful     */
   /* execution and a negative value on errors.                         */
static int SendDataCommand(ParameterList_t *TempParam)
{
   int           LEConnectionIndex;
   BD_ADDR_t     BD_ADDR;
   DeviceInfo_t *DeviceInfo;
    char BT_address[12]="cc78ab7945c2";

   /* Make sure that all of the parameters required for this function   */
   /* appear to be at least semi-valid.                                 */
  // if((TempParam) && (TempParam->NumberofParameters >= 2) && (TempParam->Params[1].intParam > 0) && (TempParam->Params[0].strParam) && (BTPS_StringLength(TempParam->Params[0].strParam) >= (sizeof(BD_ADDR_t)*2)))
   //{
      /* Convert the parameter to a Bluetooth Device Address.           */
      StrToBD_ADDR(BT_address, &BD_ADDR);

      /* Find the LE Connection Index for this connection.              */
      if((LEConnectionIndex = FindLEIndexByAddress(BD_ADDR)) >= 0)
      {
         /* Check to see if we are sending to another port.             */
         if(!(LEContextInfo[LEConnectionIndex].SPPLEBufferInfo.SendInfo.BytesToSend))
         {
            /* Get the device info for the connection device.           */
            if((DeviceInfo = SearchDeviceInfoEntryByBD_ADDR(&DeviceInfoList, LEContextInfo[LEConnectionIndex].ConnectionBD_ADDR)) != NULL)
            {
               /* Get the count of the number of bytes to send.         */
               LEContextInfo[LEConnectionIndex].SPPLEBufferInfo.SendInfo.BytesToSend  = (Word_t)DataStrLen;//(DWord_t)TempParam->Params[1].intParam;
               LEContextInfo[LEConnectionIndex].SPPLEBufferInfo.SendInfo.BytesSent    = 0;

               /* Kick start the send process.                          */
               SPPLESendProcess(&(LEContextInfo[LEConnectionIndex]), DeviceInfo);
            }
            else
               Display(("No Device Info.\r\n"));
         }
         else
            Display(("Send Currently in progress.\r\n"));
      }
      else
      {
         /* No matching ConnectionBD_ADDR.                              */
         Display(("No connection with BD_ADDR %s exists.\r\n", TempParam->Params[0].strParam));
      }
  /* }
   else
      DisplayUsage("LESEND [BD_ADDR] [Number of Bytes to send]\r\n");*/

   return(0);
}

[Karl Ylvisaker]

Hello again,

I was under the impression from your earlier comments that you currently were using the nRF as the peripheral device?
The code you have shared in your last reply seem to be for your CC250MODA device - which I am not familiar with. If there is a problem with this device, then I rather recommend that you contact Texas Instrument regarding this.

Nevertheless, giving the code a quick look, it looks to me like you are indeed scheduling a single read every 10 ms. Instead of setting up a scheduler to do a reading every 10 ms - when you already know that you will be receiving a packet every 10 ms - I suggest making use of the generated BLE Radio events (RX complete events) to start the processing of your data. I am not sure how this is implemented on the CC250MODA device, but I am sure they will generate an interrupt or event upon the completion of a BLE transfer.

Looking forward to resolving this issue,

Best regards,
Karl

[sharmelaraju]

Thanks for the reply.

I have tried  cc2564moda Bluetooth(central) with  cc2564moda Bluetooth(peripheral) .With this communication it is working fine.But not with the nrf52840  controller. can you please give me some solution.

[Karl Ylvisaker]

Hello again,

sharmelaraju said:

I have tried  cc2564moda Bluetooth(central) with  cc2564moda Bluetooth(peripheral) .With this communication it is working fine.

That is very strange to hear. Are you saying that the cc2564moda peripheral behaves differently with a cc2564moda, without any changes to the peripheral code? Could you detail how it is different - do you not see the occasional double or triple message appear on the debug terminal of the peripheral?
I do not think this is likely.

From the logs you sent, it is evident that the nRF sends all the data as expected when configured as the central. 10 ms connection intervals delivering your custom data to the peripheral.

Do I have it correctly that you in your cc2564moda peripheral code use a 10 ms timer to trigger reading of the BLE RX buffer?
In the case that I was correct:
Did you attempt what I suggested in my last comment - switching the cc2564moda peripheral code to instead react to radio RX events rather than a 10 ms timer? I think this would solve your problem, as the central is sending everything it is supposed to, when it is supposed to, according to the logs.
It would also free up resources on your peripheral advice, and conform more to best-practice principles of embedded development.

Looking forward to hearing from you,

Best regards,
Karl