ble sending 4 bytes of data with custom service

RE: ble sending 4 bytes of data with custom service

Jørgen Holmefjord — Wed, 21 Apr 2021 11:36:30 GMT

m_conn_handle is usually assigned in the CONNECTED event. This is from the ble_app_template example in SDK 17.0.2:

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

RE: ble sending 4 bytes of data with custom service

kefom — Mon, 19 Apr 2021 18:57:50 GMT

i think my error is caused because i cant change connection handle it stays as BLE_CONN_HANDLE_INVALID and i tried some coding and now when i connect to the device my connection handle becames 0 "m_conn_handle = 0" so it becames null what can i do to fix this thanks again for your help.

Best regards

Efe

RE: ble sending 4 bytes of data with custom service

kefom — Mon, 19 Apr 2021 17:12:50 GMT

Hi Jorgen first of all thank you now its not giving any error but again its not updating data my init data is 0 and it always stays like that it does not change and like i said i dont get any error message

static void pres_value_update(presvalue)
{
ret_code_t err_code;
err_code = ble_cus_pres_level_update(&m_cus, presvalue , m_conn_handle);
if(err_code != NRF_SUCCESS &&
err_code != NRF_ERROR_INVALID_STATE &&
err_code != NRF_ERROR_RESOURCES &&
err_code != NRF_ERROR_BUSY &&
err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING &&
err_code != BLE_ERROR_INVALID_CONN_HANDLE)
{ 
APP_ERROR_CHECK(err_code);
}
}

i am putting a stop point here but i cant see the value of err_code do you have any guess what the problem could be ?

Best regards and thanks

Efe

RE: ble sending 4 bytes of data with custom service

Jørgen Holmefjord — Mon, 19 Apr 2021 13:46:19 GMT

Hi,

I can't find any error codes corresponding to that value, but my guess would be that ble_cus_pres_level_update() is called with p_cus->conn_handle = BLE_CONN_HANDLE_INVALID, which will cause it to return without any return statement. The return code could then possibly be some garbage data from RAM (it looks like it could be a pointer-address). Try returning an error from all calls, for instance like this:

uint32_t ble_cus_pres_level_update(ble_cus_t * p_cus, uint32_t presvalue, uint16_t conn_handle)
{
	if (p_cus->conn_handle != BLE_CONN_HANDLE_INVALID)
	{
		ble_gatts_hvx_params_t params;
		uint16_t len = sizeof(presvalue);

		memset(&params, 0, sizeof(params));
		params.type   = BLE_GATT_HVX_NOTIFICATION;
		params.handle = p_cus->bme280_presvalue_char_handles.value_handle;
		params.p_data = (uint8_t*)presvalue;
		params.p_len  = &len;

		 return sd_ble_gatts_hvx(p_cus->conn_handle, &params);
	}
	else
	{
		return BLE_ERROR_INVALID_CONN_HANDLE;
	}
}

Then you can filter this error code like the others:

static void pres_value_update(presvalue)
{
    ret_code_t err_code;
    err_code = ble_cus_pres_level_update(&m_cus, presvalue , m_conn_handle);
    if(err_code != NRF_SUCCESS &&
    err_code != NRF_ERROR_INVALID_STATE &&
    err_code != NRF_ERROR_RESOURCES &&
    err_code != NRF_ERROR_BUSY &&
    err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING &&
    err_code != BLE_ERROR_INVALID_CONN_HANDLE)
    { 
        APP_ERROR_CHECK(err_code);
    }
}

Best regards,
Jørgen