/*
* Copyright (C) 2014 BlueKitchen GmbH
*
* 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 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 the copyright holders nor the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* 4. Any redistribution, use, or modification is done solely for
* personal benefit and not for any commercial purpose or for
* monetary gain.
*
* THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
* RINGWALD 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.
*
* Please inquire about commercial licensing options at
* contact@bluekitchen-gmbh.com
*
*/
#define BTSTACK_FILE__ "nordic_spp_le_streamer.c"
// *****************************************************************************
/* EXAMPLE_START(nordic_spp_le_streamer): LE Nordic SPP-like Streamer Server
*
* @text All newer operating systems provide GATT Client functionality.
* This example shows how to get a maximal throughput via BLE:
* - send whenever possible,
* - use the max ATT MTU.
*
* @text In theory, we should also update the connection parameters, but we already get
* a connection interval of 30 ms and there's no public way to use a shorter
* interval with iOS (if we're not implementing an HID device).
*
* @text Note: To start the streaming, run the example.
* On remote device use some GATT Explorer, e.g. LightBlue, BLExplr to enable notifications.
*/
// *****************************************************************************
#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "btstack.h"
#include "ble/gatt-service/nordic_spp_service_server.h"
// nordic_spp_le_streamer.gatt contains the declaration of the provided GATT Services + Characteristics
// nordic_spp_le_streamer.h contains the binary representation of nordic_spp_le_streamer.gatt
// it is generated by the build system by calling: $BTSTACK_ROOT/tool/compile_gatt.py nordic_spp_le_streamer.gatt nordic_spp_le_streamer.h
// it needs to be regenerated when the GATT Database declared in nordic_spp_le_streamer.gatt file is modified
#include "nordic_spp_le_streamer.h"
#define REPORT_INTERVAL_MS 3000
#define MAX_NR_CONNECTIONS 3
const uint8_t adv_data[] = {
// Flags general discoverable, BR/EDR not supported
2, BLUETOOTH_DATA_TYPE_FLAGS, 0x06,
// Name
8, BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME, 'n', 'R', 'F',' ', 'S', 'P', 'P',
// UUID ...
17, BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS, 0x9e, 0xca, 0xdc, 0x24, 0xe, 0xe5, 0xa9, 0xe0, 0x93, 0xf3, 0xa3, 0xb5, 0x1, 0x0, 0x40, 0x6e,
};
const uint8_t adv_data_len = sizeof(adv_data);
static btstack_packet_callback_registration_t hci_event_callback_registration;
// support for multiple clients
typedef struct {
char name;
int le_notification_enabled;
hci_con_handle_t connection_handle;
int counter;
char test_data[200];
int test_data_len;
uint32_t test_data_sent;
uint32_t test_data_start;
btstack_context_callback_registration_t send_request;
} nordic_spp_le_streamer_connection_t;
static nordic_spp_le_streamer_connection_t nordic_spp_le_streamer_connections[MAX_NR_CONNECTIONS];
// round robin sending
static int connection_index;
static void init_connections(void){
// track connections
int i;
for (i=0;i<MAX_NR_CONNECTIONS;i++){
nordic_spp_le_streamer_connections[i].connection_handle = HCI_CON_HANDLE_INVALID;
nordic_spp_le_streamer_connections[i].name = 'A' + i;
}
}
static nordic_spp_le_streamer_connection_t * connection_for_conn_handle(hci_con_handle_t conn_handle){
int i;
for (i=0;i<MAX_NR_CONNECTIONS;i++){
if (nordic_spp_le_streamer_connections[i].connection_handle == conn_handle) return &nordic_spp_le_streamer_connections[i];
}
return NULL;
}
static void next_connection_index(void){
connection_index++;
if (connection_index == MAX_NR_CONNECTIONS){
connection_index = 0;
}
}
/*
* @section Track throughput
* @text We calculate the throughput by setting a start time and measuring the amount of
* data sent. After a configurable REPORT_INTERVAL_MS, we print the throughput in kB/s
* and reset the counter and start time.
*/
/* LISTING_START(tracking): Tracking throughput */
static void test_reset(nordic_spp_le_streamer_connection_t * context){
context->test_data_start = btstack_run_loop_get_time_ms();
context->test_data_sent = 0;
}
static void test_track_sent(nordic_spp_le_streamer_connection_t * context, int bytes_sent){
context->test_data_sent += bytes_sent;
// evaluate
uint32_t now = btstack_run_loop_get_time_ms();
uint32_t time_passed = now - context->test_data_start;
if (time_passed < REPORT_INTERVAL_MS) return;
// print speed
int bytes_per_second = context->test_data_sent * 1000 / time_passed;
printf("%c: %"PRIu32" bytes sent-> %u.%03u kB/s\n", context->name, context->test_data_sent, bytes_per_second / 1000, bytes_per_second % 1000);
// restart
context->test_data_start = now;
context->test_data_sent = 0;
}
/* LISTING_END(tracking): Tracking throughput */
/*
* @section HCI Packet Handler
*
* @text The packet handler prints the welcome message and requests a connection paramter update for LE Connections
*/
/* LISTING_START(packetHandler): Packet Handler */
static void hci_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
UNUSED(channel);
UNUSED(size);
uint16_t conn_interval;
hci_con_handle_t con_handle;
if (packet_type != HCI_EVENT_PACKET) return;
switch (hci_event_packet_get_type(packet)) {
case BTSTACK_EVENT_STATE:
// BTstack activated, get started
if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) {
printf("To start the streaming, please run nRF Toolbox -> UART to connect.\n");
}
break;
case HCI_EVENT_LE_META:
switch (hci_event_le_meta_get_subevent_code(packet)) {
case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
// print connection parameters (without using float operations)
con_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
conn_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
printf("LE Connection - Connection Interval: %u.%02u ms\n", conn_interval * 125 / 100, 25 * (conn_interval & 3));
printf("LE Connection - Connection Latency: %u\n", hci_subevent_le_connection_complete_get_conn_latency(packet));
// request min con interval 15 ms for iOS 11+
printf("LE Connection - Request 15 ms connection interval\n");
gap_request_connection_parameter_update(con_handle, 12, 12, 0, 0x0048);
break;
case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
// print connection parameters (without using float operations)
con_handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
conn_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
printf("LE Connection - Connection Param update - connection interval %u.%02u ms, latency %u\n", conn_interval * 125 / 100,
25 * (conn_interval & 3), hci_subevent_le_connection_update_complete_get_conn_latency(packet));
break;
default:
break;
}
break;
default:
break;
}
}
/* LISTING_END */
/*
* @section ATT Packet Handler
*
* @text The packet handler is used to setup and tear down the spp-over-gatt connection and its MTU
*/
/* LISTING_START(packetHandler): Packet Handler */
static void att_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
UNUSED(channel);
UNUSED(size);
if (packet_type != HCI_EVENT_PACKET) return;
int mtu;
nordic_spp_le_streamer_connection_t * context;
switch (hci_event_packet_get_type(packet)) {
case ATT_EVENT_CONNECTED:
// setup new
context = connection_for_conn_handle(HCI_CON_HANDLE_INVALID);
if (!context) break;
context->counter = 'A';
context->test_data_len = ATT_DEFAULT_MTU - 4; // -1 for nordic 0x01 packet type
context->connection_handle = att_event_connected_get_handle(packet);
break;
case ATT_EVENT_MTU_EXCHANGE_COMPLETE:
mtu = att_event_mtu_exchange_complete_get_MTU(packet) - 3;
context = connection_for_conn_handle(att_event_mtu_exchange_complete_get_handle(packet));
if (!context) break;
context->test_data_len = btstack_min(mtu - 3, sizeof(context->test_data));
printf("%c: ATT MTU = %u => use test data of len %u\n", context->name, mtu, context->test_data_len);
break;
case ATT_EVENT_DISCONNECTED:
context = connection_for_conn_handle(att_event_disconnected_get_handle(packet));
if (!context) break;
// free connection
printf("%c: Disconnect\n", context->name);
context->le_notification_enabled = 0;
context->connection_handle = HCI_CON_HANDLE_INVALID;
break;
default:
break;
}
}
/* LISTING_END */
/*
* @section Streamer
*
* @text The streamer function checks if notifications are enabled and if a notification can be sent now.
* It creates some test data - a single letter that gets increased every time - and tracks the data sent.
*/
/* LISTING_START(streamer): Streaming code */
static void nordic_can_send(void * some_context){
UNUSED(some_context);
// find next active streaming connection
int old_connection_index = connection_index;
while (1){
// active found?
if ((nordic_spp_le_streamer_connections[connection_index].connection_handle != HCI_CON_HANDLE_INVALID) &&
(nordic_spp_le_streamer_connections[connection_index].le_notification_enabled)) break;
// check next
next_connection_index();
// none found
if (connection_index == old_connection_index) return;
}
nordic_spp_le_streamer_connection_t * context = &nordic_spp_le_streamer_connections[connection_index];
// create test data
context->counter++;
if (context->counter > 'Z') context->counter = 'A';
memset(context->test_data, context->counter, context->test_data_len);
// send
nordic_spp_service_server_send(context->connection_handle, (uint8_t*) context->test_data, context->test_data_len);
// track
test_track_sent(context, context->test_data_len);
// request next send event
nordic_spp_service_server_request_can_send_now(&context->send_request, context->connection_handle);
// check next
next_connection_index();
}
/* LISTING_END */
static void nordic_spp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
hci_con_handle_t con_handle;
nordic_spp_le_streamer_connection_t * context;
switch (packet_type){
case HCI_EVENT_PACKET:
if (hci_event_packet_get_type(packet) != HCI_EVENT_GATTSERVICE_META) break;
switch (hci_event_gattservice_meta_get_subevent_code(packet)){
case GATTSERVICE_SUBEVENT_SPP_SERVICE_CONNECTED:
con_handle = gattservice_subevent_spp_service_connected_get_con_handle(packet);
context = connection_for_conn_handle(con_handle);
if (!context) break;
context->le_notification_enabled = 1;
test_reset(context);
context->send_request.callback = &nordic_can_send;
nordic_spp_service_server_request_can_send_now(&context->send_request, context->connection_handle);
break;
case GATTSERVICE_SUBEVENT_SPP_SERVICE_DISCONNECTED:
con_handle = HCI_CON_HANDLE_INVALID;
context = connection_for_conn_handle(con_handle);
if (!context) break;
context->le_notification_enabled = 0;
break;
default:
break;
}
break;
case RFCOMM_DATA_PACKET:
printf("RECV: ");
printf_hexdump(packet, size);
context = connection_for_conn_handle((hci_con_handle_t) channel);
if (!context) break;
test_track_sent(context, size);
break;
default:
break;
}
}
int btstack_main(void);
int btstack_main(void){
// register for HCI events
hci_event_callback_registration.callback = &hci_packet_handler;
hci_add_event_handler(&hci_event_callback_registration);
l2cap_init();
// setup LE device DB
le_device_db_init();
// setup SM: Display only
sm_init();
// setup ATT server
att_server_init(profile_data, NULL, NULL);
// setup Nordic SPP service
nordic_spp_service_server_init(&nordic_spp_packet_handler);
// register for ATT events
att_server_register_packet_handler(att_packet_handler);
// setup advertisements
uint16_t adv_int_min = 0x0030;
uint16_t adv_int_max = 0x0030;
uint8_t adv_type = 0;
bd_addr_t null_addr;
memset(null_addr, 0, 6);
gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00);
gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data);
gap_advertisements_enable(1);
// init client state
init_connections();
// turn on!
hci_power_control(HCI_POWER_ON);
return 0;
}
/* EXAMPLE_END */