-
Notifications
You must be signed in to change notification settings - Fork 118
/
main.cpp
657 lines (552 loc) · 23.5 KB
/
main.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
/* mbed Microcontroller Library
* Copyright (c) 2006-2018 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <events/mbed_events.h>
#include "ble/BLE.h"
#include "pretty_printer.h"
#include "mbed-trace/mbed_trace.h"
/** This example demonstrates all the basic setup required
* to advertise and scan.
*
* It contains a single class that performs both scans and advertisements.
*
* The demonstrations happens in sequence, after each "mode" ends
* the demo jumps to the next mode to continue.
*
* You may connect to the device during advertising and if you advertise
* this demo will try to connect during the scanning phase. Connection
* will terminate the phase early. At the end of the phase some stats
* will be shown about the phase.
*/
/* demo config */
/* you can adjust these parameters and see the effect on the performance */
/* Advertising parameters are mainly defined by an advertising type and
* and an interval between advertisements. Lower interval increases the
* chances of being seen at the cost of increased power usage.
*
* The Bluetooth controller may run concurrent operations with the radio;
* to help it, a minimum and maximum advertising interval should be
* provided.
*
* Most bluetooth time units are specific to each operation. For example
* adv_interval_t is expressed in multiples of 625 microseconds. If precision
* is not require you may use a conversion from milliseconds.
*/
static const ble::AdvertisingParameters advertising_params(
ble::advertising_type_t::CONNECTABLE_UNDIRECTED,
ble::adv_interval_t(ble::millisecond_t(25)), /* this could also be expressed as ble::adv_interval_t(40) */
ble::adv_interval_t(ble::millisecond_t(50)) /* this could also be expressed as ble::adv_interval_t(80) */
);
/* if the controller support it we can advertise multiple sets */
static const ble::AdvertisingParameters extended_advertising_params(
ble::advertising_type_t::NON_CONNECTABLE_UNDIRECTED,
ble::adv_interval_t(600),
ble::adv_interval_t(800)
);
static const std::chrono::milliseconds advertising_duration = 10000ms;
/* Scanning happens repeatedly and is defined by:
* - The scan interval which is the time (in 0.625us) between each scan cycle.
* - The scan window which is the scanning time (in 0.625us) during a cycle.
* If the scanning process is active, the local device sends scan requests
* to discovered peer to get additional data.
*/
static const ble::ScanParameters scan_params(
ble::phy_t::LE_1M,
ble::scan_interval_t(80),
ble::scan_window_t(60),
false /* active scanning */
);
static const ble::scan_duration_t scan_duration(ble::millisecond_t(10000));
/* config end */
events::EventQueue event_queue;
using namespace std::chrono;
using std::milli;
using namespace std::literals::chrono_literals;
/* Delay between steps */
static const std::chrono::milliseconds delay = 3000ms;
/** Demonstrate advertising, scanning and connecting */
class GapDemo : private mbed::NonCopyable<GapDemo>, public ble::Gap::EventHandler
{
public:
GapDemo(BLE& ble, events::EventQueue& event_queue) :
_ble(ble),
_gap(ble.gap()),
_event_queue(event_queue)
{
}
~GapDemo()
{
if (_ble.hasInitialized()) {
_ble.shutdown();
}
}
/** Start BLE interface initialisation */
void run()
{
/* handle gap events */
_gap.setEventHandler(this);
ble_error_t error = _ble.init(this, &GapDemo::on_init_complete);
if (error) {
print_error(error, "Error returned by BLE::init");
return;
}
/* this will not return until shutdown */
_event_queue.dispatch_forever();
}
private:
/** This is called when BLE interface is initialised and starts the first mode */
void on_init_complete(BLE::InitializationCompleteCallbackContext *event)
{
if (event->error) {
print_error(event->error, "Error during the initialisation");
return;
}
print_mac_address();
/* setup the default phy used in connection to 2M to reduce power consumption */
if (_gap.isFeatureSupported(ble::controller_supported_features_t::LE_2M_PHY)) {
ble::phy_set_t phys(/* 1M */ false, /* 2M */ true, /* coded */ false);
ble_error_t error = _gap.setPreferredPhys(/* tx */&phys, /* rx */&phys);
/* PHY 2M communication will only take place if both peers support it */
if (error) {
print_error(error, "GAP::setPreferedPhys failed");
}
} else {
/* otherwise it will use 1M by default */
}
/* all calls are serialised on the user thread through the event queue */
_event_queue.call(this, &GapDemo::advertise);
}
/** Set up and start advertising */
void advertise()
{
ble_error_t error = _gap.setAdvertisingParameters(ble::LEGACY_ADVERTISING_HANDLE, advertising_params);
if (error) {
print_error(error, "Gap::setAdvertisingParameters() failed");
return;
}
/* to create a payload we'll use a helper class that builds a valid payload */
/* AdvertisingDataSimpleBuilder is a wrapper over AdvertisingDataBuilder that allocated the buffer for us */
ble::AdvertisingDataSimpleBuilder<ble::LEGACY_ADVERTISING_MAX_SIZE> data_builder;
/* builder methods can be chained together as they return the builder object */
data_builder.setFlags().setName("Legacy Set");
/* Set payload for the set */
error = _gap.setAdvertisingPayload(ble::LEGACY_ADVERTISING_HANDLE, data_builder.getAdvertisingData());
if (error) {
print_error(error, "Gap::setAdvertisingPayload() failed");
return;
}
/* Start advertising the set */
error = _gap.startAdvertising(ble::LEGACY_ADVERTISING_HANDLE);
if (error) {
print_error(error, "Gap::startAdvertising() failed");
return;
}
printf(
"\r\nAdvertising started (type: 0x%x, interval: [%d : %d]ms)\r\n",
advertising_params.getType(),
advertising_params.getMinPrimaryInterval().valueInMs(),
advertising_params.getMaxPrimaryInterval().valueInMs()
);
#if BLE_FEATURE_EXTENDED_ADVERTISING
/* if we support extended advertising we'll also additionally advertise another set at the same time */
if (_gap.isFeatureSupported(ble::controller_supported_features_t::LE_EXTENDED_ADVERTISING)) {
/* With Bluetooth 5; it is possible to advertise concurrently multiple
* payloads at different rate. The combination of payload and its associated
* parameters is named an advertising set. To refer to these advertising
* sets the Bluetooth system use an advertising set handle that needs to
* be created first.
* The only exception is the legacy advertising handle which is usable
* on Bluetooth 4 and Bluetooth 5 system. It is created at startup and
* its lifecycle is managed by the system.
*/
ble_error_t error = _gap.createAdvertisingSet(&_extended_adv_handle, extended_advertising_params);
if (error) {
print_error(error, "Gap::createAdvertisingSet() failed");
return;
}
/* we can reuse the builder, we just replace the name */
data_builder.setName("Extended Set");
/* Set payload for the set */
error = _gap.setAdvertisingPayload(_extended_adv_handle, data_builder.getAdvertisingData());
if (error) {
print_error(error, "Gap::setAdvertisingPayload() failed");
return;
}
/* Start advertising the set */
error = _gap.startAdvertising(_extended_adv_handle);
if (error) {
print_error(error, "Gap::startAdvertising() failed");
return;
}
printf(
"Advertising started (type: 0x%x, interval: [%d : %d]ms)\r\n",
extended_advertising_params.getType(),
extended_advertising_params.getMinPrimaryInterval().valueInMs(),
extended_advertising_params.getMaxPrimaryInterval().valueInMs()
);
}
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
_demo_duration.reset();
_demo_duration.start();
/* this will stop advertising if no connection takes place in the meantime */
_cancel_handle = _event_queue.call_in(advertising_duration, [this]{ end_advertising_mode(); });
}
/** Set up and start scanning */
void scan()
{
ble_error_t error = _gap.setScanParameters(scan_params);
if (error) {
print_error(error, "Error caused by Gap::setScanParameters");
return;
}
/* start scanning and attach a callback that will handle advertisements
* and scan requests responses */
error = _gap.startScan(scan_duration);
if (error) {
print_error(error, "Error caused by Gap::startScan");
return;
}
printf("\r\nScanning started (interval: %dms, window: %dms, timeout: %dms).\r\n",
scan_params.get1mPhyConfiguration().getInterval().valueInMs(),
scan_params.get1mPhyConfiguration().getWindow().valueInMs(),
scan_duration.valueInMs());
_demo_duration.reset();
_demo_duration.start();
}
/* helper function to hide the casts */
int read_demo_duration_in_ms()
{
return duration_cast<duration<int, milli>>(_demo_duration.elapsed_time()).count();
}
private:
/* Gap::EventHandler */
/** Look at scan payload to find a peer device and connect to it */
void onAdvertisingReport(const ble::AdvertisingReportEvent &event) override
{
/* keep track of scan events for performance reporting */
_scan_count++;
/* don't bother with analysing scan result if we're already connecting */
if (_is_connecting) {
return;
}
/* only look at events from devices at a close range */
if (event.getRssi() < -65) {
return;
}
ble::AdvertisingDataParser adv_parser(event.getPayload());
/* parse the advertising payload, looking for a discoverable device */
while (adv_parser.hasNext()) {
ble::AdvertisingDataParser::element_t field = adv_parser.next();
/* skip non discoverable device */
if (field.type != ble::adv_data_type_t::FLAGS ||
field.value.size() != 1 ||
!ble::adv_data_flags_t(field.value[0]).getGeneralDiscoverable()) {
continue;
}
/* connect to a discoverable device */
/* abort timeout as the mode will end on disconnection */
_event_queue.cancel(_cancel_handle);
printf("We found a connectable device\r\n");
ble_error_t error = _gap.connect(
event.getPeerAddressType(),
event.getPeerAddress(),
ble::ConnectionParameters() // use the default connection parameters
);
if (error) {
print_error(error, "Error caused by Gap::connect");
return;
}
/* we may have already scan events waiting
* to be processed so we need to remember
* that we are already connecting and ignore them */
_is_connecting = true;
return;
}
}
void onAdvertisingEnd(const ble::AdvertisingEndEvent &event) override
{
ble::advertising_handle_t adv_handle = event.getAdvHandle();
if (event.getStatus() == BLE_ERROR_UNSPECIFIED) {
printf("Error: Failed to stop advertising set %d\r\n", adv_handle);
} else {
printf("Stopped advertising set %d\r\n", adv_handle);
if (event.getStatus() == BLE_ERROR_TIMEOUT) {
printf("Stopped due to timeout\r\n");
} else if (event.getStatus() == BLE_ERROR_LIMIT_REACHED) {
printf("Stopped due to max number of adv events reached\r\n");
} else if (event.getStatus() == BLE_ERROR_NONE) {
if (event.isConnected()) {
printf("Stopped early due to connection\r\n");
} else {
printf("Stopped due to user request\r\n");
}
}
}
#if BLE_FEATURE_EXTENDED_ADVERTISING
if (event.getAdvHandle() == _extended_adv_handle) {
/* we were waiting for it to stop before destroying it and starting scanning */
ble_error_t error = _gap.destroyAdvertisingSet(_extended_adv_handle);
if (error) {
print_error(error, "Error caused by Gap::destroyAdvertisingSet");
}
_extended_adv_handle = ble::INVALID_ADVERTISING_HANDLE;
_is_in_scanning_phase = true;
_event_queue.call_in(delay, [this]{ scan(); });
}
#endif //BLE_FEATURE_EXTENDED_ADVERTISING
}
void onAdvertisingStart(const ble::AdvertisingStartEvent &event) override
{
printf("Advertising set %d started\r\n", event.getAdvHandle());
}
void onScanTimeout(const ble::ScanTimeoutEvent&) override
{
printf("Stopped scanning due to timeout parameter\r\n");
_event_queue.call(this, &GapDemo::end_scanning_mode);
}
/** This is called by Gap to notify the application we connected,
* in our case it immediately disconnects */
void onConnectionComplete(const ble::ConnectionCompleteEvent &event) override
{
_is_connecting = false;
_demo_duration.stop();
#if BLE_FEATURE_EXTENDED_ADVERTISING
if (!_is_in_scanning_phase) {
/* if we have more than one advertising sets one of them might still be active */
if (_extended_adv_handle != ble::INVALID_ADVERTISING_HANDLE) {
/* if it's still active, stop it */
if (_gap.isAdvertisingActive(_extended_adv_handle)) {
_gap.stopAdvertising(_extended_adv_handle);
} else if (_gap.isAdvertisingActive(ble::LEGACY_ADVERTISING_HANDLE)) {
_gap.stopAdvertising(ble::LEGACY_ADVERTISING_HANDLE);
}
}
}
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
if (event.getStatus() != BLE_ERROR_NONE) {
print_error(event.getStatus(), "Connection failed");
return;
}
printf("Connected in %dms\r\n", read_demo_duration_in_ms());
/* cancel the connect timeout since we connected */
_event_queue.cancel(_cancel_handle);
_cancel_handle = _event_queue.call_in(
delay,
[this, handle=event.getConnectionHandle()]{
_gap.disconnect(handle, ble::local_disconnection_reason_t::USER_TERMINATION);
}
);
}
/** This is called by Gap to notify the application we disconnected,
* in our case it calls next_demo_mode() to progress the demo */
void onDisconnectionComplete(const ble::DisconnectionCompleteEvent &event) override
{
printf("Disconnected\r\n");
/* if it wasn't us disconnecting then we should cancel our attempt */
if (event.getReason() == ble::disconnection_reason_t::REMOTE_USER_TERMINATED_CONNECTION) {
_event_queue.cancel(_cancel_handle);
}
if (_is_in_scanning_phase) {
_event_queue.call(this, &GapDemo::end_scanning_mode);
} else {
_event_queue.call(this, &GapDemo::end_advertising_mode);
}
}
/**
* Implementation of Gap::EventHandler::onReadPhy
*/
void onReadPhy(
ble_error_t error,
ble::connection_handle_t connectionHandle,
ble::phy_t txPhy,
ble::phy_t rxPhy
) override
{
if (error) {
printf(
"Phy read on connection %d failed with error code %s\r\n",
connectionHandle, BLE::errorToString(error)
);
} else {
printf(
"Phy read on connection %d - Tx Phy: %s, Rx Phy: %s\r\n",
connectionHandle, phy_to_string(txPhy), phy_to_string(rxPhy)
);
}
}
/**
* Implementation of Gap::EventHandler::onPhyUpdateComplete
*/
void onPhyUpdateComplete(
ble_error_t error,
ble::connection_handle_t connectionHandle,
ble::phy_t txPhy,
ble::phy_t rxPhy
) override
{
if (error) {
printf(
"Phy update on connection: %d failed with error code %s\r\n",
connectionHandle, BLE::errorToString(error)
);
} else {
printf(
"Phy update on connection %d - Tx Phy: %s, Rx Phy: %s\r\n",
connectionHandle, phy_to_string(txPhy), phy_to_string(rxPhy)
);
}
}
/**
* Implementation of Gap::EventHandler::onDataLengthChange
*/
void onDataLengthChange(
ble::connection_handle_t connectionHandle,
uint16_t txSize,
uint16_t rxSize
) override
{
printf(
"Data length changed on the connection %d.\r\n"
"Maximum sizes for over the air packets are:\r\n"
"%d octets for transmit and %d octets for receive.\r\n",
connectionHandle, txSize, rxSize
);
}
private:
/** Finish the mode by shutting down advertising or scanning and move to the next mode. */
void end_scanning_mode()
{
print_scanning_performance();
ble_error_t error = _gap.stopScan();
if (error) {
print_error(error, "Error caused by Gap::stopScan");
}
_is_in_scanning_phase = false;
_scan_count = 0;
_event_queue.call_in(delay, this, &GapDemo::advertise);
}
void end_advertising_mode()
{
print_advertising_performance();
printf("Requesting stop advertising.\r\n");
_gap.stopAdvertising(ble::LEGACY_ADVERTISING_HANDLE);
#if BLE_FEATURE_EXTENDED_ADVERTISING
if (_extended_adv_handle != ble::INVALID_ADVERTISING_HANDLE) {
/* if it's still active, stop it */
if (_gap.isAdvertisingActive(_extended_adv_handle)) {
ble_error_t error = _gap.stopAdvertising(_extended_adv_handle);
if (error) {
print_error(error, "Error caused by Gap::stopAdvertising");
}
}
}
/* we have to wait before we destroy it until it's stopped */
#else
_is_in_scanning_phase = true;
_event_queue.call_in(delay, [this]{ scan(); });
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
}
/** print some information about our radio activity */
void print_scanning_performance()
{
/* measure time from mode start, may have been stopped by timeout */
uint16_t duration_ms = read_demo_duration_in_ms();
/* convert ms into timeslots for accurate calculation as internally
* all durations are in timeslots (0.625ms) */
uint16_t duration_ts = ble::scan_interval_t(ble::millisecond_t(duration_ms)).value();
uint16_t interval_ts = scan_params.get1mPhyConfiguration().getInterval().value();
uint16_t window_ts = scan_params.get1mPhyConfiguration().getWindow().value();
/* this is how long we scanned for in timeslots */
uint16_t rx_ts = (duration_ts / interval_ts) * window_ts;
/* convert to milliseconds */
uint16_t rx_ms = ble::scan_interval_t(rx_ts).valueInMs();
printf(
"We have scanned for %dms with an interval of %d"
" timeslots and a window of %d timeslots\r\n",
duration_ms, interval_ts, window_ts
);
printf("We have been listening on the radio for at least %dms\r\n", rx_ms);
}
/** print some information about our radio activity */
void print_advertising_performance()
{
/* measure time from mode start, may have been stopped by timeout */
uint16_t duration_ms = read_demo_duration_in_ms();
/* convert ms into timeslots for accurate calculation as internally
* all durations are in timeslots (0.625ms) */
uint16_t duration_ts = ble::adv_interval_t(ble::millisecond_t(duration_ms)).value();
uint16_t interval_ts = advertising_params.getMaxPrimaryInterval().value();
/* this is how many times we advertised */
uint16_t events = (duration_ts / interval_ts);
uint16_t extended_events = 0;
#if BLE_FEATURE_EXTENDED_ADVERTISING
if (_extended_adv_handle != ble::INVALID_ADVERTISING_HANDLE) {
duration_ts = ble::adv_interval_t(ble::millisecond_t(duration_ms)).value();
interval_ts = extended_advertising_params.getMaxPrimaryInterval().value();
/* this is how many times we advertised */
extended_events = (duration_ts / interval_ts);
}
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
printf("We have advertised for %dms\r\n", duration_ms);
/* non-scannable and non-connectable advertising
* skips rx events saving on power consumption */
if (advertising_params.getType() == ble::advertising_type_t::NON_CONNECTABLE_UNDIRECTED) {
printf("We created at least %d tx events\r\n", events);
} else {
printf("We created at least %d tx and rx events\r\n", events);
}
#if BLE_FEATURE_EXTENDED_ADVERTISING
if (extended_events) {
if (extended_advertising_params.getType() == ble::advertising_type_t::NON_CONNECTABLE_UNDIRECTED) {
printf("We created at least %d tx events with extended advertising\r\n", extended_events);
} else {
printf("We created at least %d tx and rx events with extended advertising\r\n", extended_events);
}
}
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
}
private:
BLE &_ble;
ble::Gap &_gap;
events::EventQueue &_event_queue;
/* Keep track of our progress through demo modes */
bool _is_in_scanning_phase = false;
bool _is_connecting = false;
/* Remember the call id of the function on _event_queue
* so we can cancel it if we need to end the phase early */
int _cancel_handle = 0;
/* Measure performance of our advertising/scanning */
Timer _demo_duration;
size_t _scan_count = 0;
#if BLE_FEATURE_EXTENDED_ADVERTISING
ble::advertising_handle_t _extended_adv_handle = ble::INVALID_ADVERTISING_HANDLE;
#endif // BLE_FEATURE_EXTENDED_ADVERTISING
};
/** Schedule processing of events from the BLE middleware in the event queue. */
void schedule_ble_events(BLE::OnEventsToProcessCallbackContext *context)
{
event_queue.call(Callback<void()>(&context->ble, &BLE::processEvents));
}
int main()
{
mbed_trace_init();
BLE &ble = BLE::Instance();
/* this will inform us off all events so we can schedule their handling
* using our event queue */
ble.onEventsToProcess(schedule_ble_events);
GapDemo demo(ble, event_queue);
demo.run();
return 0;
}