Hi,
I am writing an APP for comunicating with my nRF peripheral. I've set the MTU size to 251 and this works fine under bluez or android.
But if I try it in iOS (>10.0) I get only 185 bytes. Is there any way to increase it with DLE (data length extension).
So far the internet says no, but as I studied the BLE 4.2 standard it should be possible?
Best regards,
C.W.
the example source code is attached.
/**
* Copyright (c) 2014 - 2017, Nordic Semiconductor ASA
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form, except as embedded into a Nordic
* Semiconductor ASA integrated circuit in a product or a software update for
* such product, must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* 3. Neither the name of Nordic Semiconductor ASA nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/** @file
*
* @defgroup ble_sdk_uart_over_ble_main main.c
* @{
* @ingroup ble_sdk_app_its_eval
* @brief UART over BLE application main file.
*
* This file contains the source code for a sample application that uses the Nordic UART service.
* This application uses the @ref srvlib_conn_params module.
*/
#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "ble_hci.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_conn_params.h"
#include "softdevice_handler.h"
#include "nrf_ble_gatt.h"
#include "app_timer.h"
#include "app_button.h"
#include "app_uart.h"
#include "app_util_platform.h"
#include "bsp.h"
#include "bsp_btn_ble.h"
#include "ble_image_transfer_service.h"
#include "nrf_gpio.h"
#include "cl_includes.h"
#include "cl_system.h"
#include "cl_hal_gpio.h"
#include "ArducamMini2MP.h"
#define NRF_LOG_MODULE_NAME "APP"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#define PCA10056_USE_FRONT_HEADER 0 /**< Use the front header (P24) for the camera module. Requires SB10-15 and SB20-25 to be soldered/cut, as described in the readme. */
#define CONN_CFG_TAG 1 /**< A tag that refers to the BLE stack configuration we set with @ref sd_ble_cfg_set. Default tag is @ref BLE_CONN_CFG_TAG_DEFAULT. */
#define APP_FEATURE_NOT_SUPPORTED BLE_GATT_STATUS_ATTERR_APP_BEGIN + 2 /**< Reply when unsupported features are requested. */
#define DEVICE_NAME "Nordic2IMAGE" /**< Name of device. Will be included in the advertising data. */
#define ITS_SERVICE_UUID_TYPE BLE_UUID_TYPE_VENDOR_BEGIN /**< UUID type for the Nordic UART Service (vendor specific). */
#define APP_ADV_INTERVAL 64 /**< The advertising interval (in units of 0.625 ms. This value corresponds to 40 ms). */
#define APP_ADV_TIMEOUT_IN_SECONDS 180 /**< The advertising timeout (in units of seconds). */
#define MIN_CONN_INTERVAL MSEC_TO_UNITS(15, UNIT_1_25_MS) /**< Minimum acceptable connection interval (20 ms), Connection interval uses 1.25 ms units. */
#define MAX_CONN_INTERVAL MSEC_TO_UNITS(15, UNIT_1_25_MS) /**< Maximum acceptable connection interval (75 ms), Connection interval uses 1.25 ms units. */
#define SLAVE_LATENCY 0 /**< Slave latency. */
#define CONN_SUP_TIMEOUT MSEC_TO_UNITS(4000, UNIT_10_MS) /**< Connection supervisory timeout (4 seconds), Supervision Timeout uses 10 ms units. */
#define FIRST_CONN_PARAMS_UPDATE_DELAY APP_TIMER_TICKS(5000) /**< Time from initiating event (connect or start of notification) to first time sd_ble_gap_conn_param_update is called (5 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY APP_TIMER_TICKS(30000) /**< Time between each call to sd_ble_gap_conn_param_update after the first call (30 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT 3 /**< Number of attempts before giving up the connection parameter negotiation. */
#define MTU_REQUEST_DELAY APP_TIMER_TICKS(2000) /**< Battery level measurement interval (ticks). */
#define DEAD_BEEF 0xDEADBEEF /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */
#define UART_TX_BUF_SIZE 256 /**< UART TX buffer size. */
#define UART_RX_BUF_SIZE 256 /**< UART RX buffer size. */
APP_TIMER_DEF(m_MTU_request_timer_id); /**< Battery timer. */
static ble_its_t m_its; /**< Structure to identify the Nordic UART Service. */
static uint16_t m_conn_handle = BLE_CONN_HANDLE_INVALID; /**< Handle of the current connection. */
static nrf_ble_gatt_t m_gatt; /**< GATT module instance. */
static ble_uuid_t m_adv_uuids[] = {{BLE_UUID_ITS_SERVICE, ITS_SERVICE_UUID_TYPE}}; /**< Universally unique service identifier. */
static uint16_t m_ble_its_max_data_len = BLE_GATT_ATT_MTU_DEFAULT - 3; /**< Maximum length of data (in bytes) that can be transmitted to the peer by the Nordic UART service module. */
static uint8_t m_new_command_received = 0;
static uint8_t m_new_resolution, m_new_phy;
static bool m_stream_mode_active = false;
static ble_its_ble_params_info_t m_ble_params_info = {20, 50, 1, 1};
static bool MTU_requested_flag = false;
using namespace CppLib;
ArducamMini2MP myCamera;
Button button1(BUTTON_1, true);
enum {APP_CMD_NOCOMMAND = 0, APP_CMD_SINGLE_CAPTURE, APP_CMD_START_STREAM, APP_CMD_STOP_STREAM,
APP_CMD_CHANGE_RESOLUTION, APP_CMD_CHANGE_PHY, APP_CMD_SEND_BLE_PARAMS};
/**@brief Function for assert macro callback.
*
* @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 analyse
* 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(DEAD_BEEF, line_num, p_file_name);
}
/**@brief Function for the GAP initialization.
*
* @details This function will set up all the necessary GAP (Generic Access Profile) parameters of
* the device. It also sets the permissions and appearance.
*/
static void gap_params_init(void)
{
uint32_t err_code;
ble_gap_conn_params_t gap_conn_params;
ble_gap_conn_sec_mode_t sec_mode;
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);
err_code = sd_ble_gap_device_name_set(&sec_mode,
(const uint8_t *) DEVICE_NAME,
strlen(DEVICE_NAME));
APP_ERROR_CHECK(err_code);
memset(&gap_conn_params, 0, sizeof(gap_conn_params));
gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;
gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
gap_conn_params.slave_latency = SLAVE_LATENCY;
gap_conn_params.conn_sup_timeout = CONN_SUP_TIMEOUT;
err_code = sd_ble_gap_ppcp_set(&gap_conn_params);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling the data from the Nordic UART Service.
*
* @details This function will process the data received from the Nordic UART BLE Service and send
* it to the UART module.
*
* @param[in] p_its Nordic UART Service structure.
* @param[in] p_data Data to be send to UART module.
* @param[in] length Length of the data.
*/
/**@snippet [Handling the data received over BLE] */
static void its_data_handler(ble_its_t * p_its, uint8_t * p_data, uint16_t length)
{
switch(p_data[0])
{
// Take picture
case APP_CMD_SINGLE_CAPTURE:
case APP_CMD_SEND_BLE_PARAMS:
m_new_command_received = p_data[0];
break;
case APP_CMD_START_STREAM:
m_stream_mode_active = true;
m_new_command_received = p_data[0];
break;
case APP_CMD_STOP_STREAM:
m_stream_mode_active = false;
m_new_command_received = p_data[0];
break;
case APP_CMD_CHANGE_RESOLUTION:
m_new_command_received = APP_CMD_CHANGE_RESOLUTION;
m_new_resolution = p_data[1];
break;
case APP_CMD_CHANGE_PHY:
m_new_command_received = APP_CMD_CHANGE_PHY;
m_new_phy = p_data[1];
break;
default:
printf("Unknown command!!\r\n");
break;
}
}
/**@snippet [Handling the data received over BLE] */
/**@brief Function for initializing services that will be used by the application.
*/
static void services_init(void)
{
uint32_t err_code;
ble_its_init_t its_init;
memset(&its_init, 0, sizeof(its_init));
its_init.data_handler = its_data_handler;
err_code = ble_its_init(&m_its, &its_init);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling an event from the Connection Parameters Module.
*
* @details This function will be called for all events in the Connection Parameters Module
* which are passed to the application.
*
* @note All this function does is to disconnect. This could have been done by simply setting
* the disconnect_on_fail config parameter, but instead we use the event handler
* mechanism to demonstrate its use.
*
* @param[in] p_evt Event received from the Connection Parameters Module.
*/
static void on_conn_params_evt(ble_conn_params_evt_t * p_evt)
{
uint32_t err_code;
if (p_evt->evt_type == BLE_CONN_PARAMS_EVT_FAILED)
{
err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
APP_ERROR_CHECK(err_code);
}
}
/**@brief Function for handling errors from the Connection Parameters module.
*
* @param[in] nrf_error Error code containing information about what went wrong.
*/
static void conn_params_error_handler(uint32_t nrf_error)
{
APP_ERROR_HANDLER(nrf_error);
}
/**@brief Function for initializing the Connection Parameters module.
*/
static void conn_params_init(void)
{
uint32_t err_code;
ble_conn_params_init_t cp_init;
memset(&cp_init, 0, sizeof(cp_init));
cp_init.p_conn_params = NULL;
cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
cp_init.next_conn_params_update_delay = NEXT_CONN_PARAMS_UPDATE_DELAY;
cp_init.max_conn_params_update_count = MAX_CONN_PARAMS_UPDATE_COUNT;
cp_init.start_on_notify_cccd_handle = BLE_GATT_HANDLE_INVALID;
cp_init.disconnect_on_fail = false;
cp_init.evt_handler = on_conn_params_evt;
cp_init.error_handler = conn_params_error_handler;
err_code = ble_conn_params_init(&cp_init);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for putting the chip into sleep mode.
*
* @note This function will not return.
*/
static void sleep_mode_enter(void)
{
uint32_t err_code = bsp_indication_set(BSP_INDICATE_IDLE);
APP_ERROR_CHECK(err_code);
// Prepare wakeup buttons.
err_code = bsp_btn_ble_sleep_mode_prepare();
APP_ERROR_CHECK(err_code);
// Go to system-off mode (this function will not return; wakeup will cause a reset).
err_code = sd_power_system_off();
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling advertising events.
*
* @details This function will be called for advertising events which are passed to the application.
*
* @param[in] ble_adv_evt Advertising event.
*/
static void on_adv_evt(ble_adv_evt_t ble_adv_evt)
{
uint32_t err_code;
switch (ble_adv_evt)
{
case BLE_ADV_EVT_FAST:
err_code = bsp_indication_set(BSP_INDICATE_ADVERTISING);
APP_ERROR_CHECK(err_code);
break;
case BLE_ADV_EVT_IDLE:
sleep_mode_enter();
break;
default:
break;
}
}
/**@brief Function for the application's SoftDevice event handler.
*
* @param[in] p_ble_evt SoftDevice event.
*/
static void on_ble_evt(ble_evt_t * p_ble_evt)
{
uint32_t err_code;
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_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;
printf("Connected\r\n");
// iOS+Android support fix
err_code = app_timer_start(m_MTU_request_timer_id, MTU_REQUEST_DELAY, NULL);
APP_ERROR_CHECK(err_code);
/* err_code = sd_ble_gattc_exchange_mtu_request(m_conn_handle, 247);
APP_ERROR_CHECK(err_code);*/
break; // BLE_GAP_EVT_CONNECTED
case BLE_GAP_EVT_DISCONNECTED:
err_code = bsp_indication_set(BSP_INDICATE_IDLE);
APP_ERROR_CHECK(err_code);
m_conn_handle = BLE_CONN_HANDLE_INVALID;
// Set the command to have the resolution returned to the default 320x240
m_new_command_received = APP_CMD_CHANGE_RESOLUTION;
m_new_resolution = 1;
m_stream_mode_active = false;
m_ble_params_info.tx_phy = m_ble_params_info.rx_phy = 1;
MTU_requested_flag=false;
printf("Disconnected\r\n");
break; // BLE_GAP_EVT_DISCONNECTED
case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
// Pairing not supported
err_code = sd_ble_gap_sec_params_reply(m_conn_handle, BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP, NULL, NULL);
APP_ERROR_CHECK(err_code);
break; // BLE_GAP_EVT_SEC_PARAMS_REQUEST
case BLE_GAP_EVT_DATA_LENGTH_UPDATE_REQUEST:
{
ble_gap_data_length_params_t dl_params;
// Clearing the struct will effectivly set members to @ref BLE_GAP_DATA_LENGTH_AUTO
memset(&dl_params, 0, sizeof(ble_gap_data_length_params_t));
err_code = sd_ble_gap_data_length_update(p_ble_evt->evt.gap_evt.conn_handle, &dl_params, NULL);
APP_ERROR_CHECK(err_code);
} break;
case BLE_GAP_EVT_CONN_PARAM_UPDATE:
{
uint16_t max_con_int = p_ble_evt->evt.gap_evt.params.conn_param_update.conn_params.max_conn_interval;
uint16_t min_con_int = p_ble_evt->evt.gap_evt.params.conn_param_update.conn_params.min_conn_interval;
m_ble_params_info.con_interval = max_con_int;
ble_its_ble_params_info_send(&m_its, &m_ble_params_info);
printf("Con params updated: CI %i, %i\r\n", (int)min_con_int, (int)max_con_int);
} break;
case BLE_GAP_EVT_PHY_UPDATE:
m_ble_params_info.tx_phy = p_ble_evt->evt.gap_evt.params.phy_update.tx_phy;
m_ble_params_info.rx_phy = p_ble_evt->evt.gap_evt.params.phy_update.rx_phy;
ble_its_ble_params_info_send(&m_its, &m_ble_params_info);
printf("Phy update: %i, %i\r\n", (int)m_ble_params_info.tx_phy, (int)m_ble_params_info.rx_phy);
break;
case BLE_GATTS_EVT_SYS_ATTR_MISSING:
// No system attributes have been stored.
err_code = sd_ble_gatts_sys_attr_set(m_conn_handle, NULL, 0, 0);
APP_ERROR_CHECK(err_code);
break; // BLE_GATTS_EVT_SYS_ATTR_MISSING
case BLE_GATTC_EVT_TIMEOUT:
// Disconnect on GATT Client timeout event.
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; // BLE_GATTC_EVT_TIMEOUT
case BLE_GATTS_EVT_TIMEOUT:
// Disconnect on GATT Server timeout event.
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; // BLE_GATTS_EVT_TIMEOUT
case BLE_EVT_USER_MEM_REQUEST:
err_code = sd_ble_user_mem_reply(p_ble_evt->evt.gattc_evt.conn_handle, NULL);
APP_ERROR_CHECK(err_code);
break; // BLE_EVT_USER_MEM_REQUEST
case BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST:
{
ble_gatts_evt_rw_authorize_request_t req;
ble_gatts_rw_authorize_reply_params_t auth_reply;
req = p_ble_evt->evt.gatts_evt.params.authorize_request;
if (req.type != BLE_GATTS_AUTHORIZE_TYPE_INVALID)
{
if ((req.request.write.op == BLE_GATTS_OP_PREP_WRITE_REQ) ||
(req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_NOW) ||
(req.request.write.op == BLE_GATTS_OP_EXEC_WRITE_REQ_CANCEL))
{
if (req.type == BLE_GATTS_AUTHORIZE_TYPE_WRITE)
{
auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_WRITE;
}
else
{
auth_reply.type = BLE_GATTS_AUTHORIZE_TYPE_READ;
}
auth_reply.params.write.gatt_status = APP_FEATURE_NOT_SUPPORTED;
err_code = sd_ble_gatts_rw_authorize_reply(p_ble_evt->evt.gatts_evt.conn_handle,
&auth_reply);
APP_ERROR_CHECK(err_code);
}
}
} break; // BLE_GATTS_EVT_RW_AUTHORIZE_REQUEST
case BLE_GATTS_EVT_EXCHANGE_MTU_REQUEST:
MTU_requested_flag=true;
break;
default:
// No implementation needed.
break;
}
}
/**@brief Function for dispatching a SoftDevice event to all modules with a SoftDevice
* event handler.
*
* @details This function is called from the SoftDevice event interrupt handler after a
* SoftDevice event has been received.
*
* @param[in] p_ble_evt SoftDevice event.
*/
static void ble_evt_dispatch(ble_evt_t * p_ble_evt)
{
ble_conn_params_on_ble_evt(p_ble_evt);
nrf_ble_gatt_on_ble_evt(&m_gatt, p_ble_evt);
ble_its_on_ble_evt(&m_its, p_ble_evt);
on_ble_evt(p_ble_evt);
ble_advertising_on_ble_evt(p_ble_evt);
bsp_btn_ble_on_ble_evt(p_ble_evt);
}
/**@brief Function for the SoftDevice initialization.
*
* @details This function initializes the SoftDevice and the BLE event interrupt.
*/
static void ble_stack_init(void)
{
uint32_t err_code;
nrf_clock_lf_cfg_t clock_lf_cfg;
clock_lf_cfg.source = NRF_CLOCK_LF_SRC_XTAL;
clock_lf_cfg.rc_ctiv = 0;
clock_lf_cfg.rc_temp_ctiv = 0;
#ifdef S140
clock_lf_cfg.xtal_accuracy = NRF_CLOCK_LF_XTAL_ACCURACY_20_PPM;
#else
clock_lf_cfg.accuracy = NRF_CLOCK_LF_ACCURACY_20_PPM;
#endif
// Initialize SoftDevice.
SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);
// Fetch the start address of the application RAM.
uint32_t ram_start = 0;
err_code = softdevice_app_ram_start_get(&ram_start);
APP_ERROR_CHECK(err_code);
// Overwrite some of the default configurations for the BLE stack.
ble_cfg_t ble_cfg;
// Configure the maximum number of connections.
memset(&ble_cfg, 0, sizeof(ble_cfg));
ble_cfg.gap_cfg.role_count_cfg.periph_role_count = BLE_GAP_ROLE_COUNT_PERIPH_DEFAULT;
ble_cfg.gap_cfg.role_count_cfg.central_role_count = 0;
ble_cfg.gap_cfg.role_count_cfg.central_sec_count = 0;
err_code = sd_ble_cfg_set(BLE_GAP_CFG_ROLE_COUNT, &ble_cfg, ram_start);
APP_ERROR_CHECK(err_code);
// Configure the maximum ATT MTU.
memset(&ble_cfg, 0x00, sizeof(ble_cfg));
ble_cfg.conn_cfg.conn_cfg_tag = CONN_CFG_TAG;
ble_cfg.conn_cfg.params.gatt_conn_cfg.att_mtu = NRF_BLE_GATT_MAX_MTU_SIZE;
err_code = sd_ble_cfg_set(BLE_CONN_CFG_GATT, &ble_cfg, ram_start);
APP_ERROR_CHECK(err_code);
// Configure the maximum event length.
memset(&ble_cfg, 0x00, sizeof(ble_cfg));
ble_cfg.conn_cfg.conn_cfg_tag = CONN_CFG_TAG;
ble_cfg.conn_cfg.params.gap_conn_cfg.event_length = 320;
ble_cfg.conn_cfg.params.gap_conn_cfg.conn_count = BLE_GAP_CONN_COUNT_DEFAULT;
err_code = sd_ble_cfg_set(BLE_CONN_CFG_GAP, &ble_cfg, ram_start);
APP_ERROR_CHECK(err_code);
// Enable BLE stack.
err_code = softdevice_enable(&ram_start);
APP_ERROR_CHECK(err_code);
// Subscribe for BLE events.
err_code = softdevice_ble_evt_handler_set(ble_evt_dispatch);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling events from the GATT library. */
void gatt_evt_handler(nrf_ble_gatt_t * p_gatt, const nrf_ble_gatt_evt_t * p_evt)
{
if ((m_conn_handle == p_evt->conn_handle) && (p_evt->evt_id == NRF_BLE_GATT_EVT_ATT_MTU_UPDATED))
{
m_ble_its_max_data_len = p_evt->params.att_mtu_effective - OPCODE_LENGTH - HANDLE_LENGTH;
m_ble_params_info.mtu = m_ble_its_max_data_len;
ble_its_ble_params_info_send(&m_its, &m_ble_params_info);
printf("Data len is set to 0x%X(%d), or maybe %i\r\n", m_ble_its_max_data_len, m_ble_its_max_data_len, p_evt->params.data_length);
}
printf("ATT MTU exchange completed. central %i peripheral %i\r\n", p_gatt->att_mtu_desired_central, p_gatt->att_mtu_desired_periph);
}
/**@brief Function for initializing the GATT library. */
void gatt_init(void)
{
ret_code_t err_code;
err_code = nrf_ble_gatt_init(&m_gatt, gatt_evt_handler);
APP_ERROR_CHECK(err_code);
err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, 64);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling events from the BSP module.
*
* @param[in] event Event generated by button press.
*/
void bsp_event_handler(bsp_event_t event)
{
uint32_t err_code;
switch (event)
{
case BSP_EVENT_SLEEP:
sleep_mode_enter();
break;
case BSP_EVENT_DISCONNECT:
err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
if (err_code != NRF_ERROR_INVALID_STATE)
{
APP_ERROR_CHECK(err_code);
}
break;
case BSP_EVENT_WHITELIST_OFF:
if (m_conn_handle == BLE_CONN_HANDLE_INVALID)
{
err_code = ble_advertising_restart_without_whitelist();
if (err_code != NRF_ERROR_INVALID_STATE)
{
APP_ERROR_CHECK(err_code);
}
}
break;
default:
break;
}
}
/**@brief Function for handling app_uart events.
*
* @details This function will receive a single character from the app_uart module and append it to
* a string. The string will be be sent over BLE when the last character received was a
* 'new line' '\n' (hex 0x0A) or if the string has reached the maximum data length.
*/
/**@snippet [Handling the data received over UART] */
void uart_event_handle(app_uart_evt_t * p_event)
{
static uint8_t data_array[BLE_ITS_MAX_DATA_LEN];
static uint8_t index = 0;
uint32_t err_code;
switch (p_event->evt_type)
{
case APP_UART_DATA_READY:
UNUSED_VARIABLE(app_uart_get(&data_array[index]));
index++;
if ((data_array[index - 1] == '\n') || (index >= (m_ble_its_max_data_len)))
{
NRF_LOG_DEBUG("Ready to send data over BLE NUS\r\n");
NRF_LOG_HEXDUMP_DEBUG(data_array, index);
do
{
err_code = ble_its_string_send(&m_its, data_array, index);
if ( (err_code != NRF_ERROR_INVALID_STATE) && (err_code != NRF_ERROR_BUSY) )
{
APP_ERROR_CHECK(err_code);
}
} while (err_code == NRF_ERROR_BUSY);
index = 0;
}
break;
case APP_UART_COMMUNICATION_ERROR:
APP_ERROR_HANDLER(p_event->data.error_communication);
break;
case APP_UART_FIFO_ERROR:
APP_ERROR_HANDLER(p_event->data.error_code);
break;
default:
break;
}
}
/**@snippet [Handling the data received over UART] */
/**@brief Function for initializing the UART module.
*/
/**@snippet [UART Initialization] */
static void uart_init(void)
{
uint32_t err_code;
app_uart_comm_params_t comm_params;
comm_params.rx_pin_no = RX_PIN_NUMBER;
comm_params.tx_pin_no = TX_PIN_NUMBER;
comm_params.rts_pin_no = RTS_PIN_NUMBER;
comm_params.cts_pin_no = CTS_PIN_NUMBER;
comm_params.flow_control = APP_UART_FLOW_CONTROL_DISABLED;
comm_params.use_parity = false;
comm_params.baud_rate = UART_BAUDRATE_BAUDRATE_Baud115200;
APP_UART_FIFO_INIT(&comm_params,
UART_RX_BUF_SIZE,
UART_TX_BUF_SIZE,
uart_event_handle,
APP_IRQ_PRIORITY_LOWEST,
err_code);
APP_ERROR_CHECK(err_code);
}
/**@snippet [UART Initialization] */
/**@brief Function for initializing the Advertising functionality.
*/
static void advertising_init(void)
{
uint32_t err_code;
ble_advdata_t advdata;
ble_advdata_t scanrsp;
ble_adv_modes_config_t options;
// Build advertising data struct to pass into @ref ble_advertising_init.
memset(&advdata, 0, sizeof(advdata));
advdata.name_type = BLE_ADVDATA_FULL_NAME;
advdata.include_appearance = false;
advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_LIMITED_DISC_MODE;
memset(&scanrsp, 0, sizeof(scanrsp));
scanrsp.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
scanrsp.uuids_complete.p_uuids = m_adv_uuids;
memset(&options, 0, sizeof(options));
options.ble_adv_fast_enabled = true;
options.ble_adv_fast_interval = APP_ADV_INTERVAL;
options.ble_adv_fast_timeout = APP_ADV_TIMEOUT_IN_SECONDS;
err_code = ble_advertising_init(&advdata, &scanrsp, &options, on_adv_evt, NULL);
APP_ERROR_CHECK(err_code);
ble_advertising_conn_cfg_tag_set(CONN_CFG_TAG);
}
static void data_len_ext_set(bool status)
{
uint8_t data_length = status ? (247 + 4) : (23 + 4);
(void) nrf_ble_gatt_data_length_set(&m_gatt, BLE_CONN_HANDLE_INVALID, data_length);
}
static void gatt_mtu_set(uint16_t att_mtu)
{
ret_code_t err_code;
err_code = nrf_ble_gatt_att_mtu_periph_set(&m_gatt, att_mtu);
APP_ERROR_CHECK(err_code);
err_code = nrf_ble_gatt_att_mtu_central_set(&m_gatt, att_mtu);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the nrf log module.
*/
static void log_init(void)
{
ret_code_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
}
static void camera_init(void)
{
#if defined(BOARD_PCA10056)
#if(PCA10056_USE_FRONT_HEADER == 1)
myCamera.pinScl = 13;
myCamera.pinSda = 15;
myCamera.pinSck = 21;
myCamera.pinMiso = 23;
myCamera.pinMosi = 25;
myCamera.pinCsn = 32 + 9;
#else
myCamera.pinScl = 27;
myCamera.pinSda = 26;
myCamera.pinSck = 32 + 15;
myCamera.pinMiso = 32 + 14;
myCamera.pinMosi = 32 + 13;
myCamera.pinCsn = 32 + 12;
#endif
#elif defined(BOARD_PCA10040)
myCamera.pinScl = 27;
myCamera.pinSda = 26;
myCamera.pinSck = 25;
myCamera.pinMiso = 24;
myCamera.pinMosi = 23;
myCamera.pinCsn = 22;
#else
#error Board not defined or not supported
#endif
myCamera.open();
myCamera.setResolution(OV2640_320x240);
}
/**@brief Function for placing the application in low power state while waiting for events.
*/
static void power_manage(void)
{
uint32_t err_code = sd_app_evt_wait();
APP_ERROR_CHECK(err_code);
}
void cpplibLogFunction(LogSeverity severity, char *module, uint32_t errorCode, char *message)
{
printf("%s - %s\r\n", module, message);
}
static void MTU_request_timeout_handler(void * p_context)
{
ret_code_t err_code;
if (!MTU_requested_flag)
{
err_code = sd_ble_gattc_exchange_mtu_request(m_conn_handle, 247);
//APP_ERROR_CHECK(err_code);
}
}
/**@brief Function for the Timer initialization.
*
* @details Initializes the timer module. This creates and starts application timers.
*/
static void timers_init(void)
{
ret_code_t err_code;
// Initialize timer module.
err_code = app_timer_init();
APP_ERROR_CHECK(err_code);
// Create timers.
err_code = app_timer_create(&m_MTU_request_timer_id,
APP_TIMER_MODE_SINGLE_SHOT,
MTU_request_timeout_handler);
APP_ERROR_CHECK(err_code);
}
/**@brief Application main function.
*/
int main(void)
{
uint32_t err_code;
uint32_t img_data_length = 0;
uint8_t img_data_buffer[255];
// Initialize.
timers_init();
uart_init();
log_init();
// Start application timers.
ble_stack_init();
gap_params_init();
gatt_init();
services_init();
advertising_init();
conn_params_init();
printf("\r\nUART Start!\r\n");
nrfSystem.setLogHandler(cpplibLogFunction);
nrfSystem.setLogDefaultSeverity(LS_DEBUG);
err_code = ble_advertising_start(BLE_ADV_MODE_FAST);
APP_ERROR_CHECK(err_code);
camera_init();
data_len_ext_set(true);
gatt_mtu_set(247);
// Enter main loop.
for (;;)
{
uint32_t image_size;
ble_gap_phys_t gap_phys_settings;
switch(m_new_command_received)
{
case APP_CMD_SINGLE_CAPTURE:
m_new_command_received = APP_CMD_NOCOMMAND;
//ble_its_send_file(&m_its, test_file, TEST_FILE_SIZE);
if(myCamera.bytesAvailable() == 0)
{
printf("Starting capture...\r\n");
myCamera.startSingleCapture();
image_size = myCamera.bytesAvailable();
printf("Capture complete: size %i bytes\r\n", (int)(image_size));
ble_its_img_info_t image_info;
image_info.file_size_bytes = image_size - 1;
ble_its_img_info_send(&m_its, &image_info);
// Flush the first byte (or the JPG image will be corrupted)
myCamera.fillBuffer(img_data_buffer, 1);
}
break;
case APP_CMD_START_STREAM:
m_new_command_received = APP_CMD_NOCOMMAND;
printf("Stream mode enabled\r\n");
break;
case APP_CMD_STOP_STREAM:
m_new_command_received = APP_CMD_NOCOMMAND;
m_stream_mode_active = false;
printf("Stream mode disabled\r\n");
break;
case APP_CMD_CHANGE_RESOLUTION:
m_new_command_received = APP_CMD_NOCOMMAND;
printf("Change resolution to mode: %i\r\n", (int)m_new_resolution);
switch(m_new_resolution)
{
case 0:
myCamera.setResolution(OV2640_160x120);
break;
case 1:
myCamera.setResolution(OV2640_320x240);
break;
case 2:
myCamera.setResolution(OV2640_640x480);
break;
case 3:
myCamera.setResolution(OV2640_800x600);
break;
case 4:
myCamera.setResolution(OV2640_1024x768);
break;
case 5:
myCamera.setResolution(OV2640_1600x1200);
break;
}
break;
case APP_CMD_CHANGE_PHY:
m_new_command_received = APP_CMD_NOCOMMAND;
printf("Attempting to change phy.\r\n");
gap_phys_settings.tx_phys = (m_new_phy == 0 ? BLE_GAP_PHY_1MBPS : BLE_GAP_PHY_2MBPS);
gap_phys_settings.rx_phys = (m_new_phy == 0 ? BLE_GAP_PHY_1MBPS : BLE_GAP_PHY_2MBPS);
#ifdef S140
sd_ble_gap_phy_request(m_its.conn_handle, &gap_phys_settings);
#else
sd_ble_gap_phy_update(m_its.conn_handle, &gap_phys_settings);
#endif
break;
case APP_CMD_SEND_BLE_PARAMS:
m_new_command_received = APP_CMD_NOCOMMAND;
ble_its_ble_params_info_send(&m_its, &m_ble_params_info);
break;
default:
break;
}
if(m_stream_mode_active)
{
if(img_data_length == 0 && myCamera.bytesAvailable() == 0)
{
myCamera.startSingleCapture();
image_size = myCamera.bytesAvailable();
ble_its_img_info_t image_info;
image_info.file_size_bytes = image_size - 1;
ble_its_img_info_send(&m_its, &image_info);
// Flush the first byte (or the JPG image will be corrupted)
myCamera.fillBuffer(img_data_buffer, 1);
}
}
if(img_data_length > 0 || myCamera.bytesAvailable() > 0)
{
if(img_data_length == 0)
{
img_data_length = myCamera.fillBuffer(img_data_buffer, m_ble_its_max_data_len);
}
if(ble_its_send_file_fragment(&m_its, img_data_buffer, img_data_length) == NRF_SUCCESS)
{
img_data_length = 0;
}
}
if(m_new_command_received == APP_CMD_NOCOMMAND)
{
power_manage();
}
}
}
/**
* @}
*/
Hi,
i've tried your example but it did not change something. I've added
data_len_ext_set(true);
gatt_mtu_set(NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
But I can still only get 185 bytes. What I am missig?
My data:
nRF52832 dev board
SDK 14.2
Softdevice S132
This is the order I am calling the routines
bool erase_bonds;
ret_code_t err_code;
log_init();
NRF_LOG_INFO("firmware compilation date and time: %s %s", __DATE__, __TIME__);
#if defined BOARD_CUSTOM
NRF_LOG_INFO("BOARD_CUSTOM");
#elif defined BOARD_PCA10040
NRF_LOG_INFO("BOARD_PCA10040");
#endif
timers_init();
buttons_leds_init(&erase_bonds);
ble_stack_init();
gap_params_init();
gatt_init();
gpio_init();
peer_manager_init();
//services_init();
// initialization of communication handler
CommHandler* communication_handler = CommHandler::getInstance();
communication_handler->nus_initialize_instance(&m_nus);
advertising_init();
conn_params_init();
advertising_start(erase_bonds);
data_len_ext_set(true);
gatt_mtu_set(NRF_SDH_BLE_GATT_MAX_MTU_SIZE);
I haven't been able to get more than 185 bytes with iOS at least(189 byte LL packet), and I don't think Apple documents what the Max MTU/data packet size is. But the minimum MTU size that must be supported is 23 bytes so there is no guarantee that you will get 251 bytes MTU with other android phones.
Another point is that our radio can't send packets larger than 251 bytes so I wouldn't expect any significant improvement in terms of throughput for MTU sizes beyond 247 bytes.
From my experience,
if you are using the SDK 15.3 and would like to get the MTU > 185 with IOS, nRF52 can't send the MTU request initiative.
You can just comment out.
I used the example (ble_app_uart) in SDK 15.3.
This solution works for iOS.
BUT if I want to connect to an Android phone now, the mtu size on smartphone side remains on 20 bytes, so no update of MTU happens @Android.
Does anyone have a solution for this problem?
Regards,
Daniel