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
advertisement_report_contains_uuid16(uint16_t uuid16,uint8_t * advertisement_report)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
handle_gatt_client_event(uint8_t packet_type,uint16_t channel,uint8_t * packet,uint16_t size)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
gatt_heart_rate_client_start(void)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
hci_event_handler(uint8_t packet_type,uint16_t channel,uint8_t * packet,uint16_t size)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
usage(const char * name)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[]);
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