Multiple interrupt during data transmition

Hello

It's not entirely clear to me what your code is doing here, but if you're sending 135 bytes with an MTU of 31 the data would have to be split into 5 packets, so perhaps it's not so strange that 5 events are triggered?

Best regards,

Einar

Hello Einar

I understand this one. Strange there is something that I send all 135 bytes in respose to this event so all data is provided completely as it declared at the add custom service . So logicaly,  soft device should split it to 5 packets and send it without generation additional events because it has all data to transnit. But in actulal case,  event handler duplicates the same 135 bytes  5 time due to unnecessary events .  From other side, logicaly, the high level application does not  must to know details of low level  for example what  size of  MTU is. it should send data and count of data that is all.

Best regards

Andrii

Are you sure all of the 135 bytes are actually duplicated for each event? Can you elaborate on how you came to this conclusion?

What version of the SDK are you using? Can you link me to the documentation of these event handlers?

-Einar

Yes I am sure :-)  because this event handler was developed by our company and registered as observer :-)

static void measurements_service_event_handler(ble_evt_t const *p_ble_evt, void *p_context)
{
    ble_measurements_service_t *service_context = (ble_measurements_service_t *)p_context;
    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GATTS_EVT_WRITE:
            on_write(service_context, p_ble_evt);
            break;
        case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
        {
            const ble_gatts_evt_rw_authorize_request_t*  req;
            
            req = &p_ble_evt->evt.gatts_evt.params.authorize_request;
            if (req->type == BLE_GATTS_AUTHORIZE_TYPE_READ)
            {
                on_read(p_ble_evt->evt.common_evt.conn_handle, service_context, req->request.read.handle);
            }
            break;
        }
        default:
            // No implementation needed.
            break;
    }
}

registration is

NRF_SDH_BLE_OBSERVER(ble_service_name_obs, BLE_LBS_BLE_OBSERVER_PRIO,
                         measurements_service_event_handler, &m_ble_measurements_service);

the BLE_GATTS_AUTHORIZE_TYPE_READ has value 0x51 mentioned above

so after receiving this message the function on_read is called . this function send 135 bytes due to this code (I was metioned this code in my first message but I repeat this one here)

ble_gatts_rw_authorize_reply_params_t auth_reply = {0};
    auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_READ;
    auth_reply.params.read.gatt_status = BLE_GATT_STATUS_SUCCESS;
    auth_reply.params.read.update = 1;

  auth_reply->params.read.p_data = get_calibraion_buff;
        auth_reply->params.read.len = 135;
        DEBUG_MSG("Size Of Spectrum = %d", auth_reply->params.read.len);

 sd_ble_gatts_rw_authorize_reply(conn_handle, auth_reply);

The sdk version is 17.0..2

Best tregards

Andrii

So your custom event handler is called 5 times, which causes the on_read function to be called 5 times?

How many packets are actually sent? Does the on_read function cause the whole 135 bytes to be sent or does it send just one packet of 31 bytes each time it's called?

Have you considered setting the MTU and LE data length to over 135 bytes, to let you send all the data in a single packet?

-Einar