[Sending big size data over BLE nrf51822]

[HSA]

Dear Nordic,

I am following this test example [https://github.com/NordicSemiconductor/nrf51-ble-app-lbs/tree/throughput-test-5.2.0] while using nrf51822 dev board.

I am unable to flash it to nrf51822 (pca10028 board). considering nRF51 SDK version 5.2.0, S110 SoftDevice version 6.0.0. Its showing error : programming failed, Invalid parameter error!

Please suggest the solution. I really need to understand this example to send big size data.

Thanks.

[Øyvind Karlsen]

Hi,

Have a look at this answer. Hopefully it will cover some of the information you are looking for.

Best regards,

Øyvind

[HSA]

@ Oyvind: Hi~ Thanks for your reply~ I understood it (well explained example)

well, there is something strange I am facing....like it sending 20 byte data once I press the button, but it continuously sending the same 20 Byte data again and again....with a non stop series. It should be auto stopped once it check for the condition [BLE_EVT_TX_COMPLETE]; but its only stop once I re-press the button. Transmitting On and Off is getting controlled by button. why so? Please clear. I want to send the data only the time when I press the button but not indefinite number of times (non stop)...... Thanks.

[Øyvind Karlsen]

It is kind of hard trying to debug this without seeing your code, if you could upload it, that would be great.

[HSA]

Hi Øyvind,

I am sharing main code portion, which I used for this application; Please have a look and suggest~ Thanks

*/ Data_Send Function (main.c) ********************************************************************/

    static void data_send(void)
    {
    uint32_t 		err_code;
    uint8_t 		data[20]        = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20};

            
    if (!m_is_sending_data)
    {
        return;
    }
    
    while (1)
    {
        err_code = ble_lbs_data_send(&m_lbs, data);
        if (err_code != NRF_SUCCESS &&
            err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
            err_code != NRF_ERROR_INVALID_STATE &&
            err_code != BLE_ERROR_NO_TX_BUFFERS)
        {
            APP_ERROR_CHECK(err_code);
        }

        // If transmission succeeded, increment payload. 
        if (err_code == NRF_SUCCESS)
        {
            data[0] += 1;
            for (uint8_t i = 0; i < BLE_LBS_DATA_CHAR_LEN-1; i++)
            {
                if (data[i] == 0)
                    ++data[i+1];
                else 
                    break;
            }
        }
        else
        {
            break;
        }

    }
}

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

*/ Data_Characteristics (ble_lbs.c) ********************************************************/

static uint32_t data_char_add(ble_lbs_t * p_lbs, const ble_lbs_init_t * p_lbs_init)
{
ble_gatts_char_md_t 			char_md;
ble_gatts_attr_md_t 			cccd_md;
ble_gatts_attr_t    			attr_char_value;
ble_uuid_t          			        ble_uuid;
ble_gatts_attr_md_t 			attr_md;


memset(&cccd_md, 0, sizeof(cccd_md));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);
cccd_md.vloc = BLE_GATTS_VLOC_STACK;

	
memset(&char_md, 0, sizeof(char_md));
char_md.char_props.read   	= 1;
char_md.char_props.notify 	= 1;
char_md.p_char_user_desc  	= NULL;
char_md.p_char_pf         	= NULL;
char_md.p_user_desc_md    	= NULL;
char_md.p_cccd_md         	= &cccd_md;
char_md.p_sccd_md         	= NULL;

	
ble_uuid.type = p_lbs->uuid_type;
ble_uuid.uuid = LBS_UUID_DATA_CHAR;
memset(&attr_md, 0, sizeof(attr_md));
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
BLE_GAP_CONN_SEC_MODE_SET_NO_ACCESS(&attr_md.write_perm);
attr_md.vloc       = BLE_GATTS_VLOC_STACK;
attr_md.rd_auth    = 0;
attr_md.wr_auth    = 0;
attr_md.vlen       = 0;

memset(&attr_char_value, 0, sizeof(attr_char_value));
attr_char_value.p_uuid       = &ble_uuid;
attr_char_value.p_attr_md    = &attr_md;
attr_char_value.init_len     = 20;//sizeof(uint8_t);	
attr_char_value.init_offs    = 0;
attr_char_value.max_len      = 20;//sizeof(uint8_t);	
attr_char_value.p_value      = NULL;

return sd_ble_gatts_characteristic_add(p_lbs->service_handle, &char_md, &attr_char_value,  
                                                             &p_lbs->data_char_handles);
																				 

}

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

**/**HVX_Notifications (ble_lbs.c)********************************************************************/

    uint32_t ble_lbs_data_send(ble_lbs_t * p_lbs, uint8_t data[BLE_LBS_DATA_CHAR_LEN])
 {

  ble_gatts_hvx_params_t params;
  uint16_t len = BLE_LBS_DATA_CHAR_LEN;
  memset(&params, 0, sizeof(params));
  params.type 	= BLE_GATT_HVX_NOTIFICATION;
  params.handle = p_lbs->data_char_handles.value_handle;
  params.p_data = data;
  params.p_len 	= &len;
   
  return sd_ble_gatts_hvx(p_lbs->conn_handle, &params);

 }

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

/ Data_packet_notification (ble_lbs.h)********************************************************/

#define BLE_LBS_DATA_CHAR_LEN 	20
uint32_t ble_lbs_data_send(ble_lbs_t * p_lbs, uint8_t data[BLE_LBS_DATA_CHAR_LEN]);

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

//

[Øyvind Karlsen]

You never return from your while(1) loop, meaning that it will stay there until it is interrupted by higher priority activity, such as your button press.