xref: /btstack/test/le_audio/le_audio_broadcast_sink.c (revision c007977c0f0086b39bb7885292a9621e636f3f54)
1 /*
2  * Copyright (C) 2022 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 MATTHIAS
24  * RINGWALD 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__ "le_audio_broadcast_sink.c"
39 
40 /*
41  * LE Audio Broadcast Sink
42  */
43 
44 
45 #include "btstack_config.h"
46 
47 #include <stdint.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <inttypes.h>
53 #include <fcntl.h>        // open
54 #include <errno.h>
55 
56 #include "ad_parser.h"
57 #include "bluetooth_data_types.h"
58 #include "bluetooth_gatt.h"
59 #include "btstack_debug.h"
60 #include "btstack_audio.h"
61 #include "btstack_event.h"
62 #include "btstack_run_loop.h"
63 #include "btstack_ring_buffer.h"
64 #include "btstack_stdin.h"
65 #include "btstack_util.h"
66 #include "gap.h"
67 #include "hci.h"
68 #include "hci_cmd.h"
69 #include "btstack_lc3.h"
70 #include "btstack_lc3_google.h"
71 #include "btstack_lc3plus_fraunhofer.h"
72 
73 #ifdef HAVE_POSIX_FILE_IO
74 #include "wav_util.h"
75 #endif
76 
77 // max config
78 #define MAX_NUM_BIS 2
79 #define MAX_SAMPLES_PER_FRAME 480
80 
81 // playback
82 #define MAX_NUM_LC3_FRAMES   5
83 #define MAX_BYTES_PER_SAMPLE 4
84 #define PLAYBACK_BUFFER_SIZE (MAX_NUM_LC3_FRAMES * MAX_SAMPLES_PER_FRAME * MAX_BYTES_PER_SAMPLE)
85 
86 // analysis
87 #define PACKET_PREFIX_LEN 10
88 
89 #define ANSI_COLOR_RED     "\x1b[31m"
90 #define ANSI_COLOR_GREEN   "\x1b[32m"
91 #define ANSI_COLOR_YELLOW  "\x1b[33m"
92 #define ANSI_COLOR_BLUE    "\x1b[34m"
93 #define ANSI_COLOR_MAGENTA "\x1b[35m"
94 #define ANSI_COLOR_CYAN    "\x1b[36m"
95 #define ANSI_COLOR_RESET   "\x1b[0m"
96 
97 static void show_usage(void);
98 
99 static const char * filename_wav = "le_audio_broadcast_sink.wav";
100 
101 static enum {
102     APP_W4_WORKING,
103     APP_W4_BROADCAST_ADV,
104     APP_W4_PA_AND_BIG_INFO,
105     APP_W4_BIG_SYNC_ESTABLISHED,
106     APP_STREAMING,
107     APP_IDLE
108 } app_state = APP_W4_WORKING;
109 
110 //
111 static btstack_packet_callback_registration_t hci_event_callback_registration;
112 
113 static bool have_base;
114 static bool have_big_info;
115 
116 uint32_t last_samples_report_ms;
117 uint16_t samples_received;
118 uint16_t samples_dropped;
119 uint16_t frames_per_second[MAX_NUM_BIS];
120 
121 // remote info
122 static char remote_name[20];
123 static bd_addr_t remote;
124 static bd_addr_type_t remote_type;
125 static uint8_t remote_sid;
126 static bool count_mode;
127 static bool pts_mode;
128 static bool nrf5340_audio_demo;
129 
130 
131 // broadcast info
132 static const uint8_t    big_handle = 1;
133 static hci_con_handle_t sync_handle;
134 static hci_con_handle_t bis_con_handles[MAX_NUM_BIS];
135 static unsigned int     next_bis_index;
136 static uint8_t          encryption;
137 static uint8_t          broadcast_code [] = {0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01};
138 
139 // analysis
140 static bool     last_packet_received_big;
141 static uint16_t last_packet_sequence_big;
142 static bool     last_packet_received[MAX_NUM_BIS];
143 static uint16_t last_packet_sequence[MAX_NUM_BIS];
144 static uint32_t last_packet_time_ms[MAX_NUM_BIS];
145 static uint8_t  last_packet_prefix[MAX_NUM_BIS * PACKET_PREFIX_LEN];
146 
147 // BIG Sync
148 static le_audio_big_sync_t        big_sync_storage;
149 static le_audio_big_sync_params_t big_sync_params;
150 
151 // lc3 writer
152 static uint32_t lc3_frames;
153 
154 // lc3 codec config
155 static uint16_t sampling_frequency_hz;
156 static btstack_lc3_frame_duration_t frame_duration;
157 static uint16_t number_samples_per_frame;
158 static uint16_t octets_per_frame;
159 static uint8_t  num_bis;
160 
161 // lc3 decoder
162 static bool request_lc3plus_decoder = false;
163 static bool use_lc3plus_decoder = false;
164 static const btstack_lc3_decoder_t * lc3_decoder;
165 static int16_t pcm[MAX_NUM_BIS * MAX_SAMPLES_PER_FRAME];
166 
167 static btstack_lc3_decoder_google_t google_decoder_contexts[MAX_NUM_BIS];
168 #ifdef HAVE_LC3PLUS
169 static btstack_lc3plus_fraunhofer_decoder_t fraunhofer_decoder_contexts[MAX_NUM_BIS];
170 #endif
171 static void * decoder_contexts[MAX_NR_BIS];
172 
173 // playback
174 static uint8_t playback_buffer_storage[PLAYBACK_BUFFER_SIZE];
175 static btstack_ring_buffer_t playback_buffer;
176 
177 static btstack_timer_source_t next_packet_timer;
178 static uint16_t               cached_iso_sdu_len;
179 static bool                   have_pcm[MAX_NUM_BIS];
180 
181 static void le_audio_broadcast_sink_playback(int16_t * buffer, uint16_t num_samples){
182     // called from lower-layer but guaranteed to be on main thread
183     uint32_t bytes_needed = num_samples * num_bis * 2;
184 
185     static bool underrun = true;
186 
187     log_info("Playback: need %u, have %u", num_samples, btstack_ring_buffer_bytes_available(&playback_buffer) / ( num_bis * 2));
188 
189     if (bytes_needed > btstack_ring_buffer_bytes_available(&playback_buffer)){
190         memset(buffer, 0, bytes_needed);
191         if (underrun == false){
192             log_info("Playback underrun");
193             underrun = true;
194         }
195         return;
196     }
197 
198     if (underrun){
199         underrun = false;
200         log_info("Playback started");
201     }
202     uint32_t bytes_read;
203     btstack_ring_buffer_read(&playback_buffer, (uint8_t *) buffer, bytes_needed, &bytes_read);
204     btstack_assert(bytes_read == bytes_needed);
205 }
206 
207 static void setup_lc3_decoder(void){
208     uint8_t channel;
209     for (channel = 0 ; channel < num_bis ; channel++){
210         // pick decoder
211         void * decoder_context = NULL;
212 #ifdef HAVE_LC3PLUS
213         if (use_lc3plus_decoder){
214             decoder_context = &fraunhofer_decoder_contexts[channel];
215             lc3_decoder = btstack_lc3plus_fraunhofer_decoder_init_instance(decoder_context);
216         }
217         else
218 #endif
219         {
220             decoder_context = &google_decoder_contexts[channel];
221             lc3_decoder = btstack_lc3_decoder_google_init_instance(decoder_context);
222         }
223         decoder_contexts[channel] = decoder_context;
224         lc3_decoder->configure(decoder_context, sampling_frequency_hz, frame_duration);
225     }
226     number_samples_per_frame = lc3_decoder->get_number_samples_per_frame(decoder_contexts[0]);
227     btstack_assert(number_samples_per_frame <= MAX_SAMPLES_PER_FRAME);
228 }
229 
230 static void close_files(void){
231 #ifdef HAVE_POSIX_FILE_IO
232     printf("Close files\n");
233     wav_writer_close();
234 #endif
235     const btstack_audio_sink_t * sink = btstack_audio_sink_get_instance();
236     if (sink != NULL){
237         sink->stop_stream();
238         sink->close();
239     }
240 }
241 
242 static void handle_periodic_advertisement(const uint8_t * packet, uint16_t size){
243     // nRF534_audio quirk - no BASE in periodic advertisement
244     if (nrf5340_audio_demo){
245         // hard coded config LC3
246         // default: mono bitrate 96000, 10 ms with USB audio source, 120 octets per frame
247         count_mode = 0;
248         pts_mode   = 0;
249         num_bis    = 1;
250         sampling_frequency_hz = 48000;
251         frame_duration = BTSTACK_LC3_FRAME_DURATION_10000US;
252         octets_per_frame = 120;
253         have_base = true;
254         return;
255     }
256 
257     // periodic advertisement contains the BASE
258     // TODO: BASE might be split across multiple advertisements
259     const uint8_t * adv_data = hci_subevent_le_periodic_advertising_report_get_data(packet);
260     uint16_t adv_size = hci_subevent_le_periodic_advertising_report_get_data_length(packet);
261     uint8_t adv_status = hci_subevent_le_periodic_advertising_report_get_data_status(packet);
262 
263     if (adv_status != 0) {
264         printf("Periodic Advertisement (status %u): ", adv_status);
265         printf_hexdump(adv_data, adv_size);
266         return;
267     }
268 
269     ad_context_t context;
270     for (ad_iterator_init(&context, adv_size, adv_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
271         uint8_t data_type = ad_iterator_get_data_type(&context);
272         // TODO: avoid out-of-bounds read
273         // uint8_t data_size = ad_iterator_get_data_len(&context);
274         const uint8_t * data = ad_iterator_get_data(&context);
275         uint16_t uuid;
276         switch (data_type){
277             case BLUETOOTH_DATA_TYPE_SERVICE_DATA_16_BIT_UUID:
278                 uuid = little_endian_read_16(data, 0);
279                 if (uuid == ORG_BLUETOOTH_SERVICE_BASIC_AUDIO_ANNOUNCEMENT_SERVICE){
280                     have_base = true;
281                     // Level 1: Group Level
282                     const uint8_t * base_data = &data[2];
283                     // TODO: avoid out-of-bounds read
284                     // uint16_t base_len = data_size - 2;
285                     printf("BASE:\n");
286                     uint32_t presentation_delay = little_endian_read_24(base_data, 0);
287                     printf("- presentation delay: %"PRIu32" us\n", presentation_delay);
288                     uint8_t num_subgroups = base_data[3];
289                     printf("- num subgroups: %u\n", num_subgroups);
290                     uint8_t i;
291                     uint16_t offset = 4;
292                     for (i=0;i<num_subgroups;i++){
293                         // Level 2: Subgroup Level
294                         num_bis = base_data[offset++];
295                         printf("  - num bis[%u]: %u\n", i, num_bis);
296                         // codec_id: coding format = 0x06, vendor and coded id = 0
297                         offset += 5;
298                         uint8_t codec_specific_configuration_length = base_data[offset++];
299                         const uint8_t * codec_specific_configuration = &base_data[offset];
300                         printf("  - codec specific config[%u]: ", i);
301                         printf_hexdump(codec_specific_configuration, codec_specific_configuration_length);
302                         // parse config to get sampling frequency and frame duration
303                         uint8_t codec_offset = 0;
304                         while ((codec_offset + 1) < codec_specific_configuration_length){
305                             uint8_t ltv_len = codec_specific_configuration[codec_offset++];
306                             uint8_t ltv_type = codec_specific_configuration[codec_offset];
307                             const uint32_t sampling_frequency_map[] = { 8000, 11025, 16000, 22050, 24000, 32000, 44100, 48000, 88200, 96000, 176400, 192000, 384000 };
308                             uint8_t sampling_frequency_index;
309                             uint8_t frame_duration_index;
310                             switch (ltv_type){
311                                 case 0x01: // sampling frequency
312                                     sampling_frequency_index = codec_specific_configuration[codec_offset+1];
313                                     // TODO: check range
314                                     sampling_frequency_hz = sampling_frequency_map[sampling_frequency_index - 1];
315                                     printf("    - sampling frequency[%u]: %u\n", i, sampling_frequency_hz);
316                                     break;
317                                 case 0x02: // 0 = 7.5, 1 = 10 ms
318                                     frame_duration_index =  codec_specific_configuration[codec_offset+1];
319                                     frame_duration = (frame_duration_index == 0) ? BTSTACK_LC3_FRAME_DURATION_7500US : BTSTACK_LC3_FRAME_DURATION_10000US;
320                                     printf("    - frame duration[%u]: %s ms\n", i, (frame_duration == BTSTACK_LC3_FRAME_DURATION_7500US) ? "7.5" : "10");
321                                     break;
322                                 case 0x04:  // octets per coding frame
323                                     octets_per_frame = little_endian_read_16(codec_specific_configuration, codec_offset+1);
324                                     printf("    - octets per codec frame[%u]: %u\n", i, octets_per_frame);
325                                     break;
326                                 default:
327                                     break;
328                             }
329                             codec_offset += ltv_len;
330                         }
331                         //
332                         offset += codec_specific_configuration_length;
333                         uint8_t metadata_length = base_data[offset++];
334                         const uint8_t * meta_data = &base_data[offset];
335                         offset += metadata_length;
336                         printf("  - meta data[%u]: ", i);
337                         printf_hexdump(meta_data, metadata_length);
338                         uint8_t k;
339                         for (k=0;k<num_bis;k++){
340                             // Level 3: BIS Level
341                             uint8_t bis_index = base_data[offset++];
342                             printf("    - bis index[%u][%u]: %u\n", i, k, bis_index);
343                             uint8_t codec_specific_configuration_length2 = base_data[offset++];
344                             const uint8_t * codec_specific_configuration2 = &base_data[offset];
345                             printf("    - codec specific config[%u][%u]: ", i, k);
346                             printf_hexdump(codec_specific_configuration2, codec_specific_configuration_length2);
347                             offset += codec_specific_configuration_length2;
348                         }
349                     }
350                 }
351                 break;
352             default:
353                 break;
354         }
355     }
356 }
357 
358 static void handle_big_info(const uint8_t * packet, uint16_t size){
359     printf("BIG Info advertising report\n");
360     sync_handle = hci_subevent_le_biginfo_advertising_report_get_sync_handle(packet);
361     encryption = hci_subevent_le_biginfo_advertising_report_get_encryption(packet);
362     if (encryption) {
363         printf("Stream is encrypted\n");
364     }
365     have_big_info = true;
366 }
367 
368 static void enter_create_big_sync(void){
369     // stop scanning
370     gap_stop_scan();
371 
372     // switch to lc3plus if requested and possible
373     use_lc3plus_decoder = request_lc3plus_decoder && (frame_duration == BTSTACK_LC3_FRAME_DURATION_10000US);
374 
375     // init decoder
376     setup_lc3_decoder();
377 
378     printf("Configure: %u channels, sampling rate %u, samples per frame %u, lc3plus %u\n", num_bis, sampling_frequency_hz, number_samples_per_frame, use_lc3plus_decoder);
379 
380 #ifdef HAVE_POSIX_FILE_IO
381     // create wav file
382     printf("WAV file: %s\n", filename_wav);
383     wav_writer_open(filename_wav, num_bis, sampling_frequency_hz);
384 #endif
385 
386     // init playback buffer
387     btstack_ring_buffer_init(&playback_buffer, playback_buffer_storage, PLAYBACK_BUFFER_SIZE);
388 
389     // start playback
390     // PTS 8.2 sends stereo at half speed for stereo, for now playback at half speed
391     const btstack_audio_sink_t * sink = btstack_audio_sink_get_instance();
392     if (sink != NULL){
393         uint16_t playback_speed;
394         if ((num_bis > 1) && pts_mode){
395             playback_speed = sampling_frequency_hz / num_bis;
396             printf("PTS workaround: playback at %u hz\n", playback_speed);
397         } else {
398             playback_speed = sampling_frequency_hz;
399         };
400         sink->init(num_bis, sampling_frequency_hz, le_audio_broadcast_sink_playback);
401         sink->start_stream();
402     }
403 
404     big_sync_params.big_handle = big_handle;
405     big_sync_params.sync_handle = sync_handle;
406     big_sync_params.encryption = encryption;
407     if (encryption) {
408         memcpy(big_sync_params.broadcast_code, &broadcast_code[0], 16);
409     } else {
410         memset(big_sync_params.broadcast_code, 0, 16);
411     }
412     big_sync_params.mse = 0;
413     big_sync_params.big_sync_timeout_10ms = 100;
414     big_sync_params.num_bis = num_bis;
415     uint8_t i;
416     printf("BIG Create Sync for BIS: ");
417     for (i=0;i<num_bis;i++){
418         big_sync_params.bis_indices[i] = i + 1;
419         printf("%u ", big_sync_params.bis_indices[i]);
420     }
421     printf("\n");
422     app_state = APP_W4_BIG_SYNC_ESTABLISHED;
423     gap_big_sync_create(&big_sync_storage, &big_sync_params);
424 }
425 
426 static void start_scanning() {
427     app_state = APP_W4_BROADCAST_ADV;
428     have_base = false;
429     have_big_info = false;
430     gap_set_scan_params(1, 0x30, 0x30, 0);
431     gap_start_scan();
432     printf("Start scan..\n");
433 }
434 
435 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
436     UNUSED(channel);
437     if (packet_type != HCI_EVENT_PACKET) return;
438     switch (packet[0]) {
439         case BTSTACK_EVENT_STATE:
440             switch(btstack_event_state_get_state(packet)) {
441                 case HCI_STATE_WORKING:
442                     app_state = APP_IDLE;
443 #ifdef ENABLE_DEMO_MODE
444                     start_scanning();
445 #else
446                     show_usage();
447 #endif
448                     break;
449                 case HCI_STATE_OFF:
450                     printf("Goodbye\n");
451                     exit(0);
452                     break;
453                 default:
454                     break;
455             }
456             break;
457         case GAP_EVENT_EXTENDED_ADVERTISING_REPORT:
458         {
459             if (app_state != APP_W4_BROADCAST_ADV) break;
460 
461             gap_event_extended_advertising_report_get_address(packet, remote);
462             uint8_t adv_size = gap_event_extended_advertising_report_get_data_length(packet);
463             const uint8_t * adv_data = gap_event_extended_advertising_report_get_data(packet);
464 
465             ad_context_t context;
466             bool found = false;
467             remote_name[0] = '\0';
468             uint16_t uuid;
469             for (ad_iterator_init(&context, adv_size, adv_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
470                 uint8_t data_type = ad_iterator_get_data_type(&context);
471                 uint8_t size = ad_iterator_get_data_len(&context);
472                 const uint8_t *data = ad_iterator_get_data(&context);
473                 switch (data_type){
474                     case BLUETOOTH_DATA_TYPE_SERVICE_DATA_16_BIT_UUID:
475                         uuid = little_endian_read_16(data, 0);
476                         if (uuid == ORG_BLUETOOTH_SERVICE_BROADCAST_AUDIO_ANNOUNCEMENT_SERVICE){
477                             found = true;
478                         }
479                         break;
480                     case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
481                     case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
482                         size = btstack_min(sizeof(remote_name) - 1, size);
483                         memcpy(remote_name, data, size);
484                         remote_name[size] = 0;
485                         // support for nRF5340 Audio DK
486                         if (strncmp("NRF5340", remote_name, 7) == 0){
487                             nrf5340_audio_demo = true;
488                             found = true;
489                         }
490                         break;
491                     default:
492                         break;
493                 }
494             }
495             if (!found) break;
496             remote_type = gap_event_extended_advertising_report_get_address_type(packet);
497             remote_sid = gap_event_extended_advertising_report_get_advertising_sid(packet);
498             pts_mode = strncmp("PTS-", remote_name, 4) == 0;
499             count_mode = strncmp("COUNT", remote_name, 5) == 0;
500             printf("Remote Broadcast sink found, addr %s, name: '%s' (pts-mode: %u, count: %u)\n", bd_addr_to_str(remote), remote_name, pts_mode, count_mode);
501             // ignore other advertisements
502             gap_whitelist_add(remote_type, remote);
503             gap_set_scan_params(1, 0x30, 0x30, 1);
504             // sync to PA
505             gap_periodic_advertiser_list_clear();
506             gap_periodic_advertiser_list_add(remote_type, remote, remote_sid);
507             app_state = APP_W4_PA_AND_BIG_INFO;
508             printf("Start Periodic Advertising Sync\n");
509             gap_periodic_advertising_create_sync(0x01, remote_sid, remote_type, remote, 0, 1000, 0);
510             break;
511         }
512 
513         case HCI_EVENT_LE_META:
514             switch(hci_event_le_meta_get_subevent_code(packet)) {
515                 case HCI_SUBEVENT_LE_PERIODIC_ADVERTISING_SYNC_ESTABLISHMENT:
516                     sync_handle = hci_subevent_le_periodic_advertising_sync_establishment_get_sync_handle(packet);
517                     printf("Periodic advertising sync with handle 0x%04x established\n", sync_handle);
518                     break;
519                 case HCI_SUBEVENT_LE_PERIODIC_ADVERTISING_REPORT:
520                     if (have_base) break;
521                     handle_periodic_advertisement(packet, size);
522                     if (have_base & have_big_info){
523                         enter_create_big_sync();
524                     }
525                     break;
526                 case HCI_SUBEVENT_LE_BIGINFO_ADVERTISING_REPORT:
527                     if (have_big_info) break;
528                     handle_big_info(packet, size);
529                     if (have_base & have_big_info){
530                         enter_create_big_sync();
531                     }
532                     break;
533                 case HCI_SUBEVENT_LE_BIG_SYNC_LOST:
534                     printf("BIG Sync Lost\n");
535                     {
536                         const btstack_audio_sink_t * sink = btstack_audio_sink_get_instance();
537                         if (sink != NULL) {
538                             sink->stop_stream();
539                             sink->close();
540                         }
541                     }
542                     // start over
543                     start_scanning();
544                     break;
545                 default:
546                     break;
547             }
548             break;
549         case HCI_EVENT_META_GAP:
550             switch (hci_event_gap_meta_get_subevent_code(packet)){
551                 case GAP_SUBEVENT_BIG_SYNC_CREATED: {
552                     printf("BIG Sync created with BIS Connection handles: ");
553                     uint8_t i;
554                     for (i=0;i<num_bis;i++){
555                         bis_con_handles[i] = gap_subevent_big_sync_created_get_bis_con_handles(packet, i);
556                         printf("0x%04x ", bis_con_handles[i]);
557                     }
558                     app_state = APP_STREAMING;
559                     last_packet_received_big = false;
560                     last_samples_report_ms = btstack_run_loop_get_time_ms();
561                     memset(last_packet_sequence, 0, sizeof(last_packet_sequence));
562                     memset(last_packet_received, 0, sizeof(last_packet_received));
563                     memset(pcm, 0, sizeof(pcm));
564                     printf("Start receiving\n");
565                     break;
566                 }
567                 case GAP_SUBEVENT_BIG_SYNC_STOPPED:
568                     printf("BIG Sync stopped, big_handle 0x%02x\n", gap_subevent_big_sync_stopped_get_big_handle(packet));
569                     break;
570                 default:
571                     break;
572             }
573             break;
574         default:
575             break;
576     }
577 }
578 
579 static void store_samples_in_ringbuffer(void){
580     // check if we have all channels
581     uint8_t bis_channel;
582     for (bis_channel = 0; bis_channel < num_bis ; bis_channel++){
583         if (have_pcm[bis_channel] == false) return;
584     }
585 #ifdef HAVE_POSIX_FILE_IO
586     // write wav samples
587     wav_writer_write_int16(num_bis * number_samples_per_frame, pcm);
588 #endif
589     // store samples in playback buffer
590     uint32_t bytes_to_store = num_bis * number_samples_per_frame * 2;
591     samples_received += number_samples_per_frame;
592     if (btstack_ring_buffer_bytes_free(&playback_buffer) >= bytes_to_store) {
593         btstack_ring_buffer_write(&playback_buffer, (uint8_t *) pcm, bytes_to_store);
594     } else {
595         printf("Samples dropped\n");
596         samples_dropped += number_samples_per_frame;
597     }
598     // reset
599     for (bis_channel = 0; bis_channel < num_bis ; bis_channel++){
600         have_pcm[bis_channel] = false;
601     }
602 }
603 
604 static void plc_do(uint8_t bis_channel) {// inject packet
605     uint8_t tmp_BEC_detect;
606     uint8_t BFI = 1;
607     (void) lc3_decoder->decode_signed_16(decoder_contexts[bis_channel], NULL, cached_iso_sdu_len, BFI,
608                                          &pcm[bis_channel], num_bis,
609                                          &tmp_BEC_detect);
610 
611     printf("PLC channel %u - packet sequence %u\n", bis_channel,  last_packet_sequence[bis_channel]);
612 
613     have_pcm[bis_channel] = true;
614     store_samples_in_ringbuffer();
615 }
616 
617 static void plc_missing(uint16_t packet_sequence_number) {
618     while (btstack_time16_delta(packet_sequence_number, last_packet_sequence_big) > 1){
619         uint8_t i;
620         for (i=0;i<num_bis;i++){
621             // deal with first packet missing. inject silent samples, pcm buffer is memset to zero at start
622             if (last_packet_received[i] == false){
623                 printf("PLC Missing: very first packet BIS %u missing\n", i);
624                 have_pcm[i] = true;
625                 store_samples_in_ringbuffer();
626 
627                 last_packet_received[i] = true;
628                 last_packet_sequence[i] = last_packet_sequence_big;
629                 continue;
630             }
631 
632             // missing packet if big sequence counter is higher than bis sequence counter
633             if (btstack_time16_delta(last_packet_sequence_big, last_packet_sequence[i]) > 0) {
634                 plc_do(i);
635                 last_packet_sequence[i] = last_packet_sequence_big;
636             }
637         }
638         last_packet_sequence_big++;
639     }
640 }
641 
642 static void plc_timeout(btstack_timer_source_t * timer) {
643     if (app_state != APP_STREAMING) return;
644 
645     // Restart timer. This will loose sync with ISO interval, but if we stop caring if we loose that many packets
646     uint32_t frame_duration_ms = frame_duration == BTSTACK_LC3_FRAME_DURATION_7500US ? 8 : 10;
647     btstack_run_loop_set_timer(timer, frame_duration_ms);
648     btstack_run_loop_set_timer_handler(timer, plc_timeout);
649     btstack_run_loop_add_timer(timer);
650 
651     // assume no packet received in iso interval
652     plc_missing(last_packet_sequence_big + 1);
653 }
654 
655 static void iso_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
656 
657     if (app_state != APP_STREAMING) return;
658 
659     uint16_t header = little_endian_read_16(packet, 0);
660     hci_con_handle_t con_handle = header & 0x0fff;
661     uint8_t pb_flag = (header >> 12) & 3;
662     uint8_t ts_flag = (header >> 14) & 1;
663     uint16_t iso_load_len = little_endian_read_16(packet, 2);
664 
665     uint16_t offset = 4;
666     uint32_t time_stamp = 0;
667     if (ts_flag){
668         uint32_t time_stamp = little_endian_read_32(packet, offset);
669         offset += 4;
670     }
671 
672     uint32_t receive_time_ms = btstack_run_loop_get_time_ms();
673 
674     uint16_t packet_sequence_number = little_endian_read_16(packet, offset);
675     offset += 2;
676 
677     uint16_t header_2 = little_endian_read_16(packet, offset);
678     uint16_t iso_sdu_length = header_2 & 0x3fff;
679     uint8_t packet_status_flag = (uint8_t) (header_2 >> 14);
680     offset += 2;
681 
682     if (iso_sdu_length == 0) return;
683 
684     // infer channel from con handle - only works for up to 2 channels
685     uint8_t bis_channel = (con_handle == bis_con_handles[0]) ? 0 : 1;
686 
687     if (count_mode){
688         // check for missing packet
689         uint16_t last_seq_no = last_packet_sequence[bis_channel];
690         bool packet_missed = (last_seq_no != 0) && ((last_seq_no + 1) != packet_sequence_number);
691         if (packet_missed){
692             // print last packet
693             printf("\n");
694             printf("%04x %10"PRIu32" %u ", last_seq_no, last_packet_time_ms[bis_channel], bis_channel);
695             printf_hexdump(&last_packet_prefix[num_bis*PACKET_PREFIX_LEN], PACKET_PREFIX_LEN);
696             last_seq_no++;
697 
698             printf(ANSI_COLOR_RED);
699             while (last_seq_no < packet_sequence_number){
700                 printf("%04x            %u MISSING\n", last_seq_no, bis_channel);
701                 last_seq_no++;
702             }
703             printf(ANSI_COLOR_RESET);
704 
705             // print current packet
706             printf("%04x %10"PRIu32" %u ", packet_sequence_number, receive_time_ms, bis_channel);
707             printf_hexdump(&packet[offset], PACKET_PREFIX_LEN);
708         }
709 
710         // cache current packet
711         memcpy(&last_packet_prefix[num_bis*PACKET_PREFIX_LEN], &packet[offset], PACKET_PREFIX_LEN);
712 
713     } else {
714 
715         if (last_packet_received[bis_channel]) {
716             int16_t packet_sequence_delta = btstack_time16_delta(packet_sequence_number,
717                                                                  last_packet_sequence[bis_channel]);
718             if (packet_sequence_delta < 1) {
719                 // drop delayed packet that had already been generated by PLC
720                 printf("Dropping delayed packet. Current sequence number %u, last received or generated by PLC: %u\n",
721                        packet_sequence_number, last_packet_sequence[bis_channel]);
722                 return;
723             }
724         } else {
725             if (!last_packet_received_big) {
726                 // track sequence number of very first received packet
727                 last_packet_received_big = true;
728                 last_packet_sequence_big = packet_sequence_number;
729             }
730             printf("BIS %u, first packet seq number %u\n", bis_channel, packet_sequence_number);
731             last_packet_received[bis_channel] = true;
732         }
733 
734         // assert no channel is more than one packet behind
735         plc_missing(packet_sequence_number);
736 
737         // decode codec frame
738         uint8_t tmp_BEC_detect;
739         uint8_t BFI = 0;
740         (void) lc3_decoder->decode_signed_16(decoder_contexts[bis_channel], &packet[offset], iso_sdu_length, BFI,
741                                    &pcm[bis_channel], num_bis,
742                                    &tmp_BEC_detect);
743         have_pcm[bis_channel] = true;
744         store_samples_in_ringbuffer();
745 
746         lc3_frames++;
747         frames_per_second[bis_channel]++;
748 
749         // PLC
750         cached_iso_sdu_len = iso_sdu_length;
751         uint32_t frame_duration_ms = frame_duration == BTSTACK_LC3_FRAME_DURATION_7500US ? 8 : 10;
752         uint32_t timeout_ms = frame_duration_ms * 5 / 2;
753         btstack_run_loop_remove_timer(&next_packet_timer);
754         btstack_run_loop_set_timer(&next_packet_timer, timeout_ms);
755         btstack_run_loop_set_timer_handler(&next_packet_timer, plc_timeout);
756         btstack_run_loop_add_timer(&next_packet_timer);
757 
758         uint32_t time_ms = btstack_run_loop_get_time_ms();
759         if (btstack_time_delta(time_ms, last_samples_report_ms) >= 1000){
760             last_samples_report_ms = time_ms;
761             printf("LC3 Frames: %4u - ", (int) (lc3_frames / num_bis));
762             uint8_t i;
763             for (i=0;i<num_bis;i++){
764                 printf("%u ", frames_per_second[i]);
765                 frames_per_second[i] = 0;
766             }
767             printf(" frames per second, dropped %u of %u\n", samples_dropped, samples_received);
768             samples_received = 0;
769             samples_dropped  =  0;
770         }
771     }
772 
773     last_packet_time_ms[bis_channel]  = receive_time_ms;
774     last_packet_sequence[bis_channel] = packet_sequence_number;
775 }
776 
777 static void show_usage(void){
778     printf("\n--- LE Audio Broadcast Sink Test Console ---\n");
779     printf("s - start scanning\n");
780 #ifdef HAVE_LC3PLUS
781     printf("q - use LC3plus decoder if 10 ms ISO interval is used\n");
782 #endif
783     printf("t - terminate BIS streams\n");
784     printf("x - close files and exit\n");
785     printf("---\n");
786 }
787 
788 static void stdin_process(char c){
789     switch (c){
790         case 's':
791             if (app_state != APP_IDLE) break;
792             start_scanning();
793             break;
794 #ifdef HAVE_LC3PLUS
795         case 'q':
796             printf("Use LC3plus decoder for 10 ms ISO interval...\n");
797             request_lc3plus_decoder = true;
798             break;
799 #endif
800         case 't':
801             switch (app_state){
802                 case APP_STREAMING:
803                 case APP_W4_BIG_SYNC_ESTABLISHED:
804                     app_state = APP_IDLE;
805                     close_files();
806                     printf("Terminate BIG SYNC\n");
807                     gap_big_sync_terminate(big_handle);
808                     break;
809                 default:
810                     break;
811             }
812             break;
813         case 'x':
814             close_files();
815             printf("Shutdown...\n");
816             hci_power_control(HCI_POWER_OFF);
817             break;
818         case '\n':
819         case '\r':
820             break;
821         default:
822             show_usage();
823             break;
824 
825     }
826 }
827 
828 int btstack_main(int argc, const char * argv[]);
829 int btstack_main(int argc, const char * argv[]){
830     (void) argv;
831     (void) argc;
832 
833     // register for HCI events
834     hci_event_callback_registration.callback = &packet_handler;
835     hci_add_event_handler(&hci_event_callback_registration);
836 
837     // register for ISO Packet
838     hci_register_iso_packet_handler(&iso_packet_handler);
839 
840     // turn on!
841     hci_power_control(HCI_POWER_ON);
842 
843     btstack_stdin_setup(stdin_process);
844     return 0;
845 }
846