1 /* 2 * Copyright (C) 2018 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "gatt_heart_rate_client.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(gatt_heart_rate_client): GATT Heart Rate Sensor Client 42 * 43 * @text Connects for Heart Rate Sensor and reports measurements. 44 */ 45 // ***************************************************************************** 46 47 #include <inttypes.h> 48 #include <stdint.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 53 #include "btstack.h" 54 55 // prototypes 56 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 57 58 typedef enum { 59 TC_OFF, 60 TC_IDLE, 61 TC_W4_SCAN_RESULT, 62 TC_W4_CONNECT, 63 TC_W4_SERVICE_RESULT, 64 TC_W4_HEART_RATE_MEASUREMENT_CHARACTERISTIC, 65 TC_W4_ENABLE_NOTIFICATIONS_COMPLETE, 66 TC_W4_SENSOR_LOCATION_CHARACTERISTIC, 67 TC_W4_SENSOR_LOCATION, 68 TC_CONNECTED 69 } gc_state_t; 70 71 static const char * sensor_contact_string[] = { 72 "not supported", 73 "not supported", 74 "no/poor contact", 75 "good contact" 76 }; 77 78 static bd_addr_t cmdline_addr; 79 static int cmdline_addr_found = 0; 80 81 // addr and type of device with correct name 82 static bd_addr_t le_streamer_addr; 83 static bd_addr_type_t le_streamer_addr_type; 84 85 static hci_con_handle_t connection_handle; 86 87 static gatt_client_service_t heart_rate_service; 88 static gatt_client_characteristic_t body_sensor_location_characteristic; 89 static gatt_client_characteristic_t heart_rate_measurement_characteristic; 90 91 static uint8_t body_sensor_location; 92 93 static gatt_client_notification_t notification_listener; 94 static int listener_registered; 95 96 static gc_state_t state = TC_OFF; 97 static btstack_packet_callback_registration_t hci_event_callback_registration; 98 99 100 // returns 1 if name is found in advertisement 101 static int advertisement_report_contains_uuid16(uint16_t uuid16, uint8_t * advertisement_report){ 102 // get advertisement from report event 103 const uint8_t * adv_data = gap_event_advertising_report_get_data(advertisement_report); 104 uint8_t adv_len = gap_event_advertising_report_get_data_length(advertisement_report); 105 106 // iterate over advertisement data 107 ad_context_t context; 108 int found = 0; 109 for (ad_iterator_init(&context, adv_len, adv_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){ 110 uint8_t data_type = ad_iterator_get_data_type(&context); 111 uint8_t data_size = ad_iterator_get_data_len(&context); 112 const uint8_t * data = ad_iterator_get_data(&context); 113 int i; 114 switch (data_type){ 115 case BLUETOOTH_DATA_TYPE_INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS: 116 case BLUETOOTH_DATA_TYPE_COMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS: 117 // compare common prefix 118 for (i=0; i<data_size;i+=2){ 119 if (little_endian_read_16(data, i) == uuid16) { 120 found = 1; 121 break; 122 } 123 } 124 break; 125 default: 126 break; 127 } 128 } 129 return found; 130 } 131 132 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 133 UNUSED(packet_type); 134 UNUSED(channel); 135 UNUSED(size); 136 137 uint16_t heart_rate; 138 uint8_t sensor_contact; 139 uint8_t att_status; 140 141 switch(state){ 142 case TC_W4_SERVICE_RESULT: 143 switch(hci_event_packet_get_type(packet)){ 144 case GATT_EVENT_SERVICE_QUERY_RESULT: 145 // store service (we expect only one) 146 gatt_event_service_query_result_get_service(packet, &heart_rate_service); 147 break; 148 case GATT_EVENT_QUERY_COMPLETE: 149 att_status = gatt_event_query_complete_get_att_status(packet); 150 if (att_status != ATT_ERROR_SUCCESS){ 151 printf("SERVICE_QUERY_RESULT - ATT Error 0x%02x.\n", att_status); 152 gap_disconnect(connection_handle); 153 break; 154 } 155 state = TC_W4_HEART_RATE_MEASUREMENT_CHARACTERISTIC; 156 printf("Search for Heart Rate Measurement characteristic.\n"); 157 gatt_client_discover_characteristics_for_service_by_uuid16(handle_gatt_client_event, connection_handle, &heart_rate_service, ORG_BLUETOOTH_CHARACTERISTIC_HEART_RATE_MEASUREMENT); 158 break; 159 default: 160 break; 161 } 162 break; 163 164 case TC_W4_HEART_RATE_MEASUREMENT_CHARACTERISTIC: 165 switch(hci_event_packet_get_type(packet)){ 166 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT: 167 gatt_event_characteristic_query_result_get_characteristic(packet, &heart_rate_measurement_characteristic); 168 break; 169 case GATT_EVENT_QUERY_COMPLETE: 170 att_status = gatt_event_query_complete_get_att_status(packet); 171 if (att_status != ATT_ERROR_SUCCESS){ 172 printf("CHARACTERISTIC_QUERY_RESULT - ATT Error 0x%02x.\n", att_status); 173 gap_disconnect(connection_handle); 174 break; 175 } 176 // register handler for notifications 177 listener_registered = 1; 178 gatt_client_listen_for_characteristic_value_updates(¬ification_listener, handle_gatt_client_event, connection_handle, &heart_rate_measurement_characteristic); 179 // enable notifications 180 printf("Enable Notify on Heart Rate Measurements characteristic.\n"); 181 state = TC_W4_ENABLE_NOTIFICATIONS_COMPLETE; 182 gatt_client_write_client_characteristic_configuration(handle_gatt_client_event, connection_handle, 183 &heart_rate_measurement_characteristic, GATT_CLIENT_CHARACTERISTICS_CONFIGURATION_NOTIFICATION); 184 break; 185 default: 186 break; 187 } 188 break; 189 190 case TC_W4_ENABLE_NOTIFICATIONS_COMPLETE: 191 switch(hci_event_packet_get_type(packet)){ 192 case GATT_EVENT_QUERY_COMPLETE: 193 printf("Notifications enabled, ATT status 0x%02x\n", gatt_event_query_complete_get_att_status(packet)); 194 195 state = TC_W4_SENSOR_LOCATION_CHARACTERISTIC; 196 printf("Search for Sensor Location characteristic.\n"); 197 gatt_client_discover_characteristics_for_service_by_uuid16(handle_gatt_client_event, connection_handle, &heart_rate_service, ORG_BLUETOOTH_CHARACTERISTIC_BODY_SENSOR_LOCATION); 198 break; 199 default: 200 break; 201 } 202 break; 203 204 205 case TC_W4_SENSOR_LOCATION_CHARACTERISTIC: 206 switch(hci_event_packet_get_type(packet)){ 207 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT: 208 gatt_event_characteristic_query_result_get_characteristic(packet, &body_sensor_location_characteristic); 209 break; 210 case GATT_EVENT_QUERY_COMPLETE: 211 if (gatt_event_query_complete_get_att_status(packet) != ATT_ERROR_SUCCESS){ 212 printf("CHARACTERISTIC_QUERY_RESULT - ATT Error 0x%02x.\n", packet[4]); 213 state = TC_CONNECTED; 214 break; 215 } 216 if (body_sensor_location_characteristic.value_handle == 0){ 217 printf("Sensor Location characteristic not available.\n"); 218 state = TC_CONNECTED; 219 break; 220 } 221 state = TC_W4_HEART_RATE_MEASUREMENT_CHARACTERISTIC; 222 printf("Read Body Sensor Location.\n"); 223 state = TC_W4_SENSOR_LOCATION; 224 gatt_client_read_value_of_characteristic(handle_gatt_client_event, connection_handle, &body_sensor_location_characteristic); 225 break; 226 default: 227 break; 228 } 229 break; 230 231 232 case TC_W4_SENSOR_LOCATION: 233 switch(hci_event_packet_get_type(packet)){ 234 case GATT_EVENT_CHARACTERISTIC_VALUE_QUERY_RESULT: 235 body_sensor_location = gatt_event_characteristic_value_query_result_get_value(packet)[0]; 236 printf("Sensor Location: %u\n", body_sensor_location); 237 break; 238 case GATT_EVENT_QUERY_COMPLETE: 239 state = TC_CONNECTED; 240 break; 241 default: 242 break; 243 } 244 break; 245 246 case TC_CONNECTED: 247 switch(hci_event_packet_get_type(packet)){ 248 case GATT_EVENT_NOTIFICATION: 249 if (gatt_event_notification_get_value(packet)[0] & 1){ 250 heart_rate = little_endian_read_16(gatt_event_notification_get_value(packet), 1); 251 } else { 252 heart_rate = gatt_event_notification_get_value(packet)[1]; 253 } 254 sensor_contact = (gatt_event_notification_get_value(packet)[0] >> 1) & 3; 255 printf("Heart Rate: %3u, Sensor Contact: %s\n", heart_rate, sensor_contact_string[sensor_contact]); 256 break; 257 case GATT_EVENT_QUERY_COMPLETE: 258 break; 259 case GATT_EVENT_CAN_WRITE_WITHOUT_RESPONSE: 260 break; 261 default: 262 break; 263 } 264 break; 265 266 default: 267 break; 268 } 269 } 270 271 // Either connect to remote specified on command line or start scan for device with Hear Rate Service in advertisement 272 static void gatt_heart_rate_client_start(void){ 273 if (cmdline_addr_found){ 274 printf("Connect to %s\n", bd_addr_to_str(cmdline_addr)); 275 state = TC_W4_CONNECT; 276 gap_connect(cmdline_addr, 0); 277 } else { 278 printf("Start scanning!\n"); 279 state = TC_W4_SCAN_RESULT; 280 gap_set_scan_parameters(0,0x0030, 0x0030); 281 gap_start_scan(); 282 } 283 } 284 285 static void hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 286 UNUSED(channel); 287 UNUSED(size); 288 289 if (packet_type != HCI_EVENT_PACKET) return; 290 291 uint16_t conn_interval; 292 uint8_t event = hci_event_packet_get_type(packet); 293 switch (event) { 294 case BTSTACK_EVENT_STATE: 295 // BTstack activated, get started 296 if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) { 297 gatt_heart_rate_client_start(); 298 } else { 299 state = TC_OFF; 300 } 301 break; 302 case GAP_EVENT_ADVERTISING_REPORT: 303 if (state != TC_W4_SCAN_RESULT) return; 304 // check name in advertisement 305 if (!advertisement_report_contains_uuid16(ORG_BLUETOOTH_SERVICE_HEART_RATE, packet)) return; 306 // store address and type 307 gap_event_advertising_report_get_address(packet, le_streamer_addr); 308 le_streamer_addr_type = gap_event_advertising_report_get_address_type(packet); 309 // stop scanning, and connect to the device 310 state = TC_W4_CONNECT; 311 gap_stop_scan(); 312 printf("Stop scan. Connect to device with addr %s.\n", bd_addr_to_str(le_streamer_addr)); 313 gap_connect(le_streamer_addr,le_streamer_addr_type); 314 break; 315 case HCI_EVENT_META_GAP: 316 // wait for connection complete 317 if (hci_event_gap_meta_get_subevent_code(packet) != GAP_SUBEVENT_LE_CONNECTION_COMPLETE) break; 318 if (state != TC_W4_CONNECT) return; 319 connection_handle = gap_subevent_le_connection_complete_get_connection_handle(packet); 320 // print connection parameters (without using float operations) 321 conn_interval = gap_subevent_le_connection_complete_get_conn_interval(packet); 322 printf("Connection Interval: %u.%02u ms\n", conn_interval * 125 / 100, 25 * (conn_interval & 3)); 323 printf("Connection Latency: %u\n", gap_subevent_le_connection_complete_get_conn_latency(packet)); 324 // initialize gatt client context with handle, and add it to the list of active clients 325 // query primary services 326 printf("Search for Heart Rate service.\n"); 327 state = TC_W4_SERVICE_RESULT; 328 gatt_client_discover_primary_services_by_uuid16(handle_gatt_client_event, connection_handle, ORG_BLUETOOTH_SERVICE_HEART_RATE); 329 break; 330 case HCI_EVENT_DISCONNECTION_COMPLETE: 331 // unregister listener 332 connection_handle = HCI_CON_HANDLE_INVALID; 333 if (listener_registered){ 334 listener_registered = 0; 335 gatt_client_stop_listening_for_characteristic_value_updates(¬ification_listener); 336 } 337 if (cmdline_addr_found){ 338 printf("Disconnected %s\n", bd_addr_to_str(cmdline_addr)); 339 return; 340 } 341 printf("Disconnected %s\n", bd_addr_to_str(le_streamer_addr)); 342 if (state == TC_OFF) break; 343 gatt_heart_rate_client_start(); 344 break; 345 default: 346 break; 347 } 348 } 349 350 #ifdef HAVE_BTSTACK_STDIN 351 static void usage(const char *name){ 352 fprintf(stderr, "Usage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", name); 353 fprintf(stderr, "If no argument is provided, GATT Heart Rate Client will start scanning and connect to a device that advertises the heart rate UUID.\n"); 354 fprintf(stderr, "To connect to a specific device use argument [-a].\n\n"); 355 } 356 #endif 357 358 int btstack_main(int argc, const char * argv[]); 359 int btstack_main(int argc, const char * argv[]){ 360 361 #ifdef HAVE_BTSTACK_STDIN 362 int arg; 363 cmdline_addr_found = 0; 364 365 for (arg = 1; arg < argc; arg++) { 366 if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){ 367 if (arg + 1 < argc) { 368 arg++; 369 cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr); 370 } 371 if (!cmdline_addr_found) { 372 usage(argv[0]); 373 return 1; 374 } 375 } 376 } 377 if (!cmdline_addr_found) { 378 fprintf(stderr, "No specific address specified or found; start scanning for heart rate UUID advertiser.\n"); 379 } 380 #else 381 (void)argc; 382 (void)argv; 383 #endif 384 l2cap_init(); 385 386 gatt_client_init(); 387 388 sm_init(); 389 sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT); 390 391 hci_event_callback_registration.callback = &hci_event_handler; 392 hci_add_event_handler(&hci_event_callback_registration); 393 394 // turn on! 395 hci_power_control(HCI_POWER_ON); 396 397 return 0; 398 } 399 /* EXAMPLE_END */ 400