Hi, i am trying to increase the transfer speed using the UART ove BLE application

[jrubiralta]

I need to increas the speed using the UART ove BLE application.

I try to add new characheristics to the Nordic UART Service.

I have added the UUID for this new charactheristic

#define BLE_UUID_NUS_RX2_CHARACTERISTIC 0x0004               /**< The UUID of the RX Characteristic. */

i have added the handle to the Nodrdic service Service structure

struct ble_nus_s
{
    uint8_t                         uuid_type;          /**< UUID type for Nordic UART Service Base UUID. */
    uint16_t                        service_handle;     /**< Handle of Nordic UART Service (as provided by the SoftDevice). */
    ble_gatts_char_handles_t        tx_handles;         /**< Handles related to the TX characteristic (as provided by the SoftDevice). */
    ble_gatts_char_handles_t        rx_handles;         /**< Handles related to the RX characteristic (as provided by the SoftDevice). */
    ble_gatts_char_handles_t        rx2_handles;         /**< Handles related to the RX2 characteristic (as provided by the SoftDevice). */
      blcm_link_ctx_storage_t * const p_link_ctx_storage; /**< Pointer to link context storage with handles of all current connections and its context. */
    ble_nus_data_handler_t          data_handler;       /**< Event handler to be called for handling received data. */
};

I have added the charactheristic in the ble_nus_init function

    // Add the RX2 Characteristic.
    memset(&add_char_params, 0, sizeof(add_char_params));
    add_char_params.uuid                     = BLE_UUID_NUS_RX2_CHARACTERISTIC;
    add_char_params.uuid_type                = p_nus->uuid_type;
    add_char_params.max_len                  = BLE_NUS_MAX_RX_CHAR_LEN;
    add_char_params.init_len                 = sizeof(uint8_t);
    add_char_params.is_var_len               = true;
    add_char_params.char_props.write         = 1;
    add_char_params.char_props.write_wo_resp = 1;

    add_char_params.read_access  = SEC_OPEN;
    add_char_params.write_access = SEC_OPEN;

    err_code = characteristic_add(p_nus->service_handle, &add_char_params, &p_nus->rx2_handles);
    if (err_code != NRF_SUCCESS)
    {
        return err_code;
    }

When i inspect the service with the nRF Connect APP, the new charactheristic appears as "Unknow Charactheristic"

How can i set the charactheristic's name?

If i try to add more charactheristics it return error code 4 (NRF_ERROR_NO_MEM)

How can i increase the memory stack?

Many thanks

[awneil]

...

jrubiralta said:

I need to increas the speed using the UART ove BLE

From what? To what?

Remember that the specific design goal of BLE, as the name suggests, is Low Energy - not high-speed or high-volume data transfer.

Often, it is the phone which limits the throughput.

jrubiralta said:

I try to add new characheristics

How would that help?

That seems to be an entirely unrelated question to the topic title?

[jrubiralta]

In normal opperation, the transfer speed is enauth.

When i need to update my firmware, i need biger speed.

I want to write several charactheristic at the same time to reduce the time to answer the ACK to the phone.

With one RX charactheristic, i can send 240 bytes.

With 4 RX charactheristics, i can send 240 * 8 = 1920 bytes.

The BLE Data rate is 1Mb. This means that i can send several charactheristics at the same time.

Is this possible?

Sorry, mi device id nrf52832

[jrubiralta]

Ok, i woul like to try it, How can i increase the memoty stach?

[awneil]

Have you read the tutorials on adding custom services & characteristics?

It's in there ...

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-services-a-beginners-tutorial

https://devzone.nordicsemi.com/nordic/short-range-guides/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial

[jrubiralta]

Helo, I have added 2 charactheristcs. I write the 3 charactheristics in the phone. I read the ble event poll in the main application and normaly only one charactheristic arrives. Some times arrives 2 charactheristics and somtime arrives 3 charactheristics.  
Can i write more than 1 charactheristic at a time?

void read_events_poll(void){
    
    __ALIGN(4) uint8_t evt_buffer[NRF_SDH_BLE_EVT_BUF_SIZE];
    ble_evt_t * p_ble_evt;
    uint16_t     evt_len = (uint16_t)sizeof(evt_buffer);

    ret_code_t ret_code = sd_ble_evt_get(evt_buffer, &evt_len);
    if (ret_code != NRF_SUCCESS)
        return;
    p_ble_evt = (ble_evt_t *)evt_buffer;
    nrf_section_iter_t  iter;
    for (nrf_section_iter_init(&iter, &sdh_ble_observers);
         nrf_section_iter_get(&iter) != NULL;
         nrf_section_iter_next(&iter))
    {
        nrf_sdh_ble_evt_observer_t * p_observer;
        nrf_sdh_ble_evt_handler_t    handler;

        p_observer = (nrf_sdh_ble_evt_observer_t *)nrf_section_iter_get(&iter);
        handler    = p_observer->handler;

        handler(p_ble_evt, p_observer->p_context);
    }
}



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

[awneil]

Did you read & follow through the tutorials?

How to properly post source code:

[jrubiralta]

Sorry

void read_events_poll(void){
	
	__ALIGN(4) uint8_t evt_buffer[NRF_SDH_BLE_EVT_BUF_SIZE];
	ble_evt_t * p_ble_evt;
	uint16_t     evt_len = (uint16_t)sizeof(evt_buffer);

	ret_code_t ret_code = sd_ble_evt_get(evt_buffer, &evt_len);
	if (ret_code != NRF_SUCCESS)
		return;
	p_ble_evt = (ble_evt_t *)evt_buffer;
	nrf_section_iter_t  iter;
	for (nrf_section_iter_init(&iter, &sdh_ble_observers);
		 nrf_section_iter_get(&iter) != NULL;
		 nrf_section_iter_next(&iter))
	{
		nrf_sdh_ble_evt_observer_t * p_observer;
		nrf_sdh_ble_evt_handler_t    handler;

		p_observer = (nrf_sdh_ble_evt_observer_t *)nrf_section_iter_get(&iter);
		handler    = p_observer->handler;

		handler(p_ble_evt, p_observer->p_context);
	}
}

int main(void)
{
    bool erase_bonds;

    // Initialize.
    uart_init();
    log_init();
    timers_init();
    buttons_leds_init(&erase_bonds);
    power_management_init();
    ble_stack_init();
    gap_params_init();
    gatt_init();
    services_init();
    advertising_init();
    conn_params_init();

    // Start execution.
    // printf("\r\nUART started.\r\n");
    NRF_LOG_INFO("Debug logging for UART over RTT started.");
    advertising_start();

    // Enter main loop.
    for (;;)
    {
		read_events_poll();
		sd_app_evt_wait();
    }
}

[awneil]

The more important question was 

Did you read & follow through the tutorials?