xref: /btstack/example/a2dp_source_demo.c (revision e3ba22907f903f11cd12321c31e7936b8dd1157e)
1 /*
2  * Copyright (C) 2016 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__ "a2dp_source_demo.c"
39 
40 /*
41  * a2dp_source_demo.c
42  */
43 
44 // *****************************************************************************
45 /* EXAMPLE_START(a2dp_source_demo): A2DP Source - Stream Audio and Control Volume
46  *
47  * @text This A2DP Source example demonstrates how to send an audio data stream
48  * to a remote A2DP Sink device and how to switch between two audio data sources.
49  * In addition, the AVRCP Target is used to answer queries on currently played media,
50  * as well as to handle remote playback control, i.e. play, stop, repeat, etc. If HAVE_BTSTACK_STDIN
51  * is set, press SPACE on the console to show the available AVDTP and AVRCP commands.
52  *
53  * @text To test with a remote device, e.g. a Bluetooth speaker,
54  * set the device_addr_string to the Bluetooth address of your
55  * remote device in the code, and use the UI to connect and start playback.
56  *
57  * @text For more info on BTstack audio, see our blog post
58  * [A2DP Sink and Source on STM32 F4 Discovery Board](http://bluekitchen-gmbh.com/a2dp-sink-and-source-on-stm32-f4-discovery-board/).
59  *
60  */
61 // *****************************************************************************
62 
63 
64 #include <stdint.h>
65 #include <stdio.h>
66 #include <inttypes.h>
67 #include <string.h>
68 
69 #include "btstack.h"
70 #include "hxcmod.h"
71 #include "mods/mod.h"
72 
73 // logarithmic volume reduction, samples are divided by 2^x
74 // #define VOLUME_REDUCTION 3
75 
76 //#define AVRCP_BROWSING_ENABLED
77 
78 #define NUM_CHANNELS                2
79 #define BYTES_PER_AUDIO_SAMPLE      (2*NUM_CHANNELS)
80 #define AUDIO_TIMEOUT_MS            10
81 #define TABLE_SIZE_441HZ            100
82 
83 #define SBC_STORAGE_SIZE 1030
84 
85 typedef enum {
86     STREAM_SINE = 0,
87     STREAM_MOD,
88     STREAM_PTS_TEST
89 } stream_data_source_t;
90 
91 typedef struct {
92     uint16_t a2dp_cid;
93     uint8_t  local_seid;
94     uint8_t  remote_seid;
95     uint8_t  stream_opened;
96     uint16_t avrcp_cid;
97 
98     uint32_t time_audio_data_sent; // ms
99     uint32_t acc_num_missed_samples;
100     uint32_t samples_ready;
101     btstack_timer_source_t audio_timer;
102     uint8_t  streaming;
103     int      max_media_payload_size;
104 
105     uint8_t  sbc_storage[SBC_STORAGE_SIZE];
106     uint16_t sbc_storage_count;
107     uint8_t  sbc_ready_to_send;
108 
109     uint8_t volume;
110 } a2dp_media_sending_context_t;
111 
112 static  uint8_t media_sbc_codec_capabilities[] = {
113     (AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
114     0xFF,//(AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
115     2, 53
116 };
117 
118 // input signal: pre-computed int16 sine wave, 44100 Hz at 441 Hz
119 static const int16_t sine_int16_44100[] = {
120      0,    2057,    4107,    6140,    8149,   10126,   12062,   13952,   15786,   17557,
121  19260,   20886,   22431,   23886,   25247,   26509,   27666,   28714,   29648,   30466,
122  31163,   31738,   32187,   32509,   32702,   32767,   32702,   32509,   32187,   31738,
123  31163,   30466,   29648,   28714,   27666,   26509,   25247,   23886,   22431,   20886,
124  19260,   17557,   15786,   13952,   12062,   10126,    8149,    6140,    4107,    2057,
125      0,   -2057,   -4107,   -6140,   -8149,  -10126,  -12062,  -13952,  -15786,  -17557,
126 -19260,  -20886,  -22431,  -23886,  -25247,  -26509,  -27666,  -28714,  -29648,  -30466,
127 -31163,  -31738,  -32187,  -32509,  -32702,  -32767,  -32702,  -32509,  -32187,  -31738,
128 -31163,  -30466,  -29648,  -28714,  -27666,  -26509,  -25247,  -23886,  -22431,  -20886,
129 -19260,  -17557,  -15786,  -13952,  -12062,  -10126,   -8149,   -6140,   -4107,   -2057,
130 };
131 
132 static const int num_samples_sine_int16_44100 = sizeof(sine_int16_44100) / 2;
133 
134 // input signal: pre-computed int16 sine wave, 48000 Hz at 441 Hz
135 static const int16_t sine_int16_48000[] = {
136      0,    1905,    3804,    5690,    7557,    9398,   11207,   12978,   14706,   16383,
137  18006,   19567,   21062,   22486,   23834,   25101,   26283,   27376,   28377,   29282,
138  30087,   30791,   31390,   31884,   32269,   32545,   32712,   32767,   32712,   32545,
139  32269,   31884,   31390,   30791,   30087,   29282,   28377,   27376,   26283,   25101,
140  23834,   22486,   21062,   19567,   18006,   16383,   14706,   12978,   11207,    9398,
141   7557,    5690,    3804,    1905,       0,   -1905,   -3804,   -5690,   -7557,   -9398,
142 -11207,  -12978,  -14706,  -16384,  -18006,  -19567,  -21062,  -22486,  -23834,  -25101,
143 -26283,  -27376,  -28377,  -29282,  -30087,  -30791,  -31390,  -31884,  -32269,  -32545,
144 -32712,  -32767,  -32712,  -32545,  -32269,  -31884,  -31390,  -30791,  -30087,  -29282,
145 -28377,  -27376,  -26283,  -25101,  -23834,  -22486,  -21062,  -19567,  -18006,  -16384,
146 -14706,  -12978,  -11207,   -9398,   -7557,   -5690,   -3804,   -1905,  };
147 
148 static const int num_samples_sine_int16_48000 = sizeof(sine_int16_48000) / 2;
149 
150 static const int A2DP_SOURCE_DEMO_INQUIRY_DURATION_1280MS = 12;
151 
152 typedef struct {
153     int reconfigure;
154 
155     int num_channels;
156     int sampling_frequency;
157     int block_length;
158     int subbands;
159     int min_bitpool_value;
160     int max_bitpool_value;
161     btstack_sbc_channel_mode_t      channel_mode;
162     btstack_sbc_allocation_method_t allocation_method;
163 } media_codec_configuration_sbc_t;
164 
165 static btstack_packet_callback_registration_t hci_event_callback_registration;
166 
167 // Minijambox:
168 static const char * device_addr_string = "00:21:3C:AC:F7:38";
169 
170 static bd_addr_t device_addr;
171 static bool scan_active;
172 
173 static uint8_t sdp_a2dp_source_service_buffer[150];
174 static uint8_t sdp_avrcp_target_service_buffer[200];
175 static uint8_t sdp_avrcp_controller_service_buffer[200];
176 static uint8_t device_id_sdp_service_buffer[100];
177 
178 static media_codec_configuration_sbc_t sbc_configuration;
179 static btstack_sbc_encoder_state_t sbc_encoder_state;
180 
181 static uint8_t media_sbc_codec_configuration[4];
182 static a2dp_media_sending_context_t media_tracker;
183 
184 static stream_data_source_t data_source;
185 
186 static int sine_phase;
187 static int current_sample_rate = 44100;
188 static int new_sample_rate = 44100;
189 
190 static int hxcmod_initialized;
191 static modcontext mod_context;
192 static tracker_buffer_state trkbuf;
193 
194 /* AVRCP Target context START */
195 
196 typedef struct {
197     uint8_t track_id[8];
198     uint32_t song_length_ms;
199     avrcp_playback_status_t status;
200     uint32_t song_position_ms; // 0xFFFFFFFF if not supported
201 } avrcp_play_status_info_t;
202 
203 // python -c "print('a'*512)"
204 static const char title[] = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
205 
206 avrcp_track_t tracks[] = {
207     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, 1, "Sine", "Generated", "A2DP Source Demo", "monotone", 12345},
208     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}, 2, "Nao-deceased", "Decease", "A2DP Source Demo", "vivid", 12345},
209     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03}, 3, (char *)title, "Decease", "A2DP Source Demo", "vivid", 12345},
210 };
211 int current_track_index;
212 avrcp_play_status_info_t play_info;
213 
214 /* AVRCP Target context END */
215 
216 /* @section Main Application Setup
217  *
218  * @text The Listing MainConfiguration shows how to setup AD2P Source and AVRCP services.
219  * Besides calling init() method for each service, you'll also need to register several packet handlers:
220  * - hci_packet_handler - handles legacy pairing, here by using fixed '0000' pin code.
221  * - a2dp_source_packet_handler - handles events on stream connection status (established, released), the media codec configuration, and, the commands on stream itself (open, pause, stopp).
222  * - avrcp_packet_handler - receives connect/disconnect event.
223  * - avrcp_controller_packet_handler - receives answers for sent AVRCP commands.
224  * - avrcp_target_packet_handler - receives AVRCP commands, and registered notifications.
225  * - stdin_process - used to trigger AVRCP commands to the A2DP Source device, such are get now playing info, start, stop, volume control. Requires HAVE_BTSTACK_STDIN.
226  *
227  * @text To announce A2DP Source and AVRCP services, you need to create corresponding
228  * SDP records and register them with the SDP service.
229  */
230 
231 /* LISTING_START(MainConfiguration): Setup Audio Source and AVRCP Target services */
232 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
233 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t event_size);
234 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
235 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
236 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
237 #ifdef HAVE_BTSTACK_STDIN
238 static void stdin_process(char cmd);
239 #endif
240 
241 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate);
242 
243 static int a2dp_source_and_avrcp_services_init(void){
244 
245     // Request role change on reconnecting headset to always use them in slave mode
246     hci_set_master_slave_policy(0);
247     // enabled EIR
248     hci_set_inquiry_mode(INQUIRY_MODE_RSSI_AND_EIR);
249 
250     l2cap_init();
251 
252 #ifdef ENABLE_BLE
253     // Initialize LE Security Manager. Needed for cross-transport key derivation
254     sm_init();
255 #endif
256 
257     // Initialize  A2DP Source
258     a2dp_source_init();
259     a2dp_source_register_packet_handler(&a2dp_source_packet_handler);
260 
261     // Create stream endpoint
262     avdtp_stream_endpoint_t * local_stream_endpoint = a2dp_source_create_stream_endpoint(AVDTP_AUDIO, AVDTP_CODEC_SBC, media_sbc_codec_capabilities, sizeof(media_sbc_codec_capabilities), media_sbc_codec_configuration, sizeof(media_sbc_codec_configuration));
263     if (!local_stream_endpoint){
264         printf("A2DP Source: not enough memory to create local stream endpoint\n");
265         return 1;
266     }
267 
268     // Store stream enpoint's SEP ID, as it is used by A2DP API to indentify the stream endpoint
269     media_tracker.local_seid = avdtp_local_seid(local_stream_endpoint);
270     avdtp_source_register_delay_reporting_category(media_tracker.local_seid);
271 
272     // Initialize AVRCP Service
273     avrcp_init();
274     avrcp_register_packet_handler(&avrcp_packet_handler);
275     // Initialize AVRCP Target
276     avrcp_target_init();
277     avrcp_target_register_packet_handler(&avrcp_target_packet_handler);
278 
279     // Initialize AVRCP Controller
280     avrcp_controller_init();
281     avrcp_controller_register_packet_handler(&avrcp_controller_packet_handler);
282 
283     // Initialize SDP,
284     sdp_init();
285 
286     // Create A2DP Source service record and register it with SDP
287     memset(sdp_a2dp_source_service_buffer, 0, sizeof(sdp_a2dp_source_service_buffer));
288     a2dp_source_create_sdp_record(sdp_a2dp_source_service_buffer, 0x10001, AVDTP_SOURCE_FEATURE_MASK_PLAYER, NULL, NULL);
289     sdp_register_service(sdp_a2dp_source_service_buffer);
290 
291     // Create AVRCP Target service record and register it with SDP. We receive Category 1 commands from the headphone, e.g. play/pause
292     memset(sdp_avrcp_target_service_buffer, 0, sizeof(sdp_avrcp_target_service_buffer));
293     uint16_t supported_features = AVRCP_FEATURE_MASK_CATEGORY_PLAYER_OR_RECORDER;
294 #ifdef AVRCP_BROWSING_ENABLED
295     supported_features |= AVRCP_FEATURE_MASK_BROWSING;
296 #endif
297     avrcp_target_create_sdp_record(sdp_avrcp_target_service_buffer, 0x10002, supported_features, NULL, NULL);
298     sdp_register_service(sdp_avrcp_target_service_buffer);
299 
300     // Create AVRCP Controller service record and register it with SDP. We send Category 2 commands to the headphone, e.g. volume up/down
301     memset(sdp_avrcp_controller_service_buffer, 0, sizeof(sdp_avrcp_controller_service_buffer));
302     uint16_t controller_supported_features = AVRCP_FEATURE_MASK_CATEGORY_MONITOR_OR_AMPLIFIER;
303     avrcp_controller_create_sdp_record(sdp_avrcp_controller_service_buffer, 0x10003, controller_supported_features, NULL, NULL);
304     sdp_register_service(sdp_avrcp_controller_service_buffer);
305 
306     // Register Device ID (PnP) service SDP record
307     memset(device_id_sdp_service_buffer, 0, sizeof(device_id_sdp_service_buffer));
308     device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10004, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1);
309     sdp_register_service(device_id_sdp_service_buffer);
310 
311     // Set local name with a template Bluetooth address, that will be automatically
312     // replaced with a actual address once it is available, i.e. when BTstack boots
313     // up and starts talking to a Bluetooth module.
314     gap_set_local_name("A2DP Source 00:00:00:00:00:00");
315     gap_discoverable_control(1);
316     gap_set_class_of_device(0x200408);
317 
318     // Register for HCI events.
319     hci_event_callback_registration.callback = &hci_packet_handler;
320     hci_add_event_handler(&hci_event_callback_registration);
321 
322     a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
323     data_source = STREAM_MOD;
324 
325     // Parse human readable Bluetooth address.
326     sscanf_bd_addr(device_addr_string, device_addr);
327 
328 #ifdef HAVE_BTSTACK_STDIN
329     btstack_stdin_setup(stdin_process);
330 #endif
331     return 0;
332 }
333 /* LISTING_END */
334 
335 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate){
336     if (!hxcmod_initialized){
337         hxcmod_initialized = hxcmod_init(&mod_context);
338         if (!hxcmod_initialized) {
339             printf("could not initialize hxcmod\n");
340             return;
341         }
342     }
343     current_sample_rate = sample_rate;
344     media_tracker.sbc_storage_count = 0;
345     media_tracker.samples_ready = 0;
346     hxcmod_unload(&mod_context);
347     hxcmod_setcfg(&mod_context, current_sample_rate, 16, 1, 1, 1);
348     hxcmod_load(&mod_context, (void *) &mod_data, mod_len);
349 }
350 
351 static void a2dp_demo_send_media_packet(void){
352     int num_bytes_in_frame = btstack_sbc_encoder_sbc_buffer_length();
353     int bytes_in_storage = media_tracker.sbc_storage_count;
354     uint8_t num_frames = bytes_in_storage / num_bytes_in_frame;
355     // Prepend SBC Header
356     media_tracker.sbc_storage[0] = num_frames;  // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
357     avdtp_source_stream_send_media_payload_rtp(media_tracker.a2dp_cid, media_tracker.local_seid, 0, media_tracker.sbc_storage, bytes_in_storage + 1);
358 
359     media_tracker.sbc_storage_count = 0;
360     media_tracker.sbc_ready_to_send = 0;
361 }
362 
363 static void produce_sine_audio(int16_t * pcm_buffer, int num_samples_to_write){
364     int count;
365     for (count = 0; count < num_samples_to_write ; count++){
366         switch (current_sample_rate){
367             case 44100:
368                 pcm_buffer[count * 2]     = sine_int16_44100[sine_phase];
369                 pcm_buffer[count * 2 + 1] = sine_int16_44100[sine_phase];
370                 sine_phase++;
371                 if (sine_phase >= num_samples_sine_int16_44100){
372                     sine_phase -= num_samples_sine_int16_44100;
373                 }
374                 break;
375             case 48000:
376                 pcm_buffer[count * 2]     = sine_int16_48000[sine_phase];
377                 pcm_buffer[count * 2 + 1] = sine_int16_48000[sine_phase];
378                 sine_phase++;
379                 if (sine_phase >= num_samples_sine_int16_48000){
380                     sine_phase -= num_samples_sine_int16_48000;
381                 }
382                 break;
383             default:
384                 break;
385         }
386     }
387 }
388 
389 static void produce_mod_audio(int16_t * pcm_buffer, int num_samples_to_write){
390     hxcmod_fillbuffer(&mod_context, (unsigned short *) &pcm_buffer[0], num_samples_to_write, &trkbuf);
391 }
392 
393 static void produce_audio(int16_t * pcm_buffer, int num_samples){
394     switch (data_source){
395         case STREAM_SINE:
396             produce_sine_audio(pcm_buffer, num_samples);
397             break;
398         case STREAM_MOD:
399             produce_mod_audio(pcm_buffer, num_samples);
400             break;
401         default:
402             break;
403     }
404 #ifdef VOLUME_REDUCTION
405     int i;
406     for (i=0;i<num_samples*2;i++){
407         if (pcm_buffer[i] > 0){
408             pcm_buffer[i] =     pcm_buffer[i]  >> VOLUME_REDUCTION;
409         } else {
410             pcm_buffer[i] = -((-pcm_buffer[i]) >> VOLUME_REDUCTION);
411         }
412     }
413 #endif
414 }
415 
416 static int a2dp_demo_fill_sbc_audio_buffer(a2dp_media_sending_context_t * context){
417     // perform sbc encoding
418     int total_num_bytes_read = 0;
419     unsigned int num_audio_samples_per_sbc_buffer = btstack_sbc_encoder_num_audio_frames();
420     while (context->samples_ready >= num_audio_samples_per_sbc_buffer
421         && (context->max_media_payload_size - context->sbc_storage_count) >= btstack_sbc_encoder_sbc_buffer_length()){
422 
423         int16_t pcm_frame[256*NUM_CHANNELS];
424 
425         produce_audio(pcm_frame, num_audio_samples_per_sbc_buffer);
426         btstack_sbc_encoder_process_data(pcm_frame);
427 
428         uint16_t sbc_frame_size = btstack_sbc_encoder_sbc_buffer_length();
429         uint8_t * sbc_frame = btstack_sbc_encoder_sbc_buffer();
430 
431         total_num_bytes_read += num_audio_samples_per_sbc_buffer;
432         // first byte in sbc storage contains sbc media header
433         memcpy(&context->sbc_storage[1 + context->sbc_storage_count], sbc_frame, sbc_frame_size);
434         context->sbc_storage_count += sbc_frame_size;
435         context->samples_ready -= num_audio_samples_per_sbc_buffer;
436     }
437     return total_num_bytes_read;
438 }
439 
440 static void a2dp_demo_audio_timeout_handler(btstack_timer_source_t * timer){
441     a2dp_media_sending_context_t * context = (a2dp_media_sending_context_t *) btstack_run_loop_get_timer_context(timer);
442     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
443     btstack_run_loop_add_timer(&context->audio_timer);
444     uint32_t now = btstack_run_loop_get_time_ms();
445 
446     uint32_t update_period_ms = AUDIO_TIMEOUT_MS;
447     if (context->time_audio_data_sent > 0){
448         update_period_ms = now - context->time_audio_data_sent;
449     }
450 
451     uint32_t num_samples = (update_period_ms * current_sample_rate) / 1000;
452     context->acc_num_missed_samples += (update_period_ms * current_sample_rate) % 1000;
453 
454     while (context->acc_num_missed_samples >= 1000){
455         num_samples++;
456         context->acc_num_missed_samples -= 1000;
457     }
458     context->time_audio_data_sent = now;
459     context->samples_ready += num_samples;
460 
461     if (context->sbc_ready_to_send) return;
462 
463     a2dp_demo_fill_sbc_audio_buffer(context);
464 
465     if ((context->sbc_storage_count + btstack_sbc_encoder_sbc_buffer_length()) > context->max_media_payload_size){
466         // schedule sending
467         context->sbc_ready_to_send = 1;
468         a2dp_source_stream_endpoint_request_can_send_now(context->a2dp_cid, context->local_seid);
469     }
470 }
471 
472 static void a2dp_demo_timer_start(a2dp_media_sending_context_t * context){
473     context->max_media_payload_size = btstack_min(a2dp_max_media_payload_size(context->a2dp_cid, context->local_seid), SBC_STORAGE_SIZE);
474     context->sbc_storage_count = 0;
475     context->sbc_ready_to_send = 0;
476     context->streaming = 1;
477     btstack_run_loop_remove_timer(&context->audio_timer);
478     btstack_run_loop_set_timer_handler(&context->audio_timer, a2dp_demo_audio_timeout_handler);
479     btstack_run_loop_set_timer_context(&context->audio_timer, context);
480     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
481     btstack_run_loop_add_timer(&context->audio_timer);
482 }
483 
484 static void a2dp_demo_timer_stop(a2dp_media_sending_context_t * context){
485     context->time_audio_data_sent = 0;
486     context->acc_num_missed_samples = 0;
487     context->samples_ready = 0;
488     context->streaming = 1;
489     context->sbc_storage_count = 0;
490     context->sbc_ready_to_send = 0;
491     btstack_run_loop_remove_timer(&context->audio_timer);
492 }
493 
494 static void dump_sbc_configuration(media_codec_configuration_sbc_t * configuration){
495     printf("Received media codec configuration:\n");
496     printf("    - num_channels: %d\n", configuration->num_channels);
497     printf("    - sampling_frequency: %d\n", configuration->sampling_frequency);
498     printf("    - channel_mode: %d\n", configuration->channel_mode);
499     printf("    - block_length: %d\n", configuration->block_length);
500     printf("    - subbands: %d\n", configuration->subbands);
501     printf("    - allocation_method: %d\n", configuration->allocation_method);
502     printf("    - bitpool_value [%d, %d] \n", configuration->min_bitpool_value, configuration->max_bitpool_value);
503 }
504 
505 static void a2dp_source_demo_start_scanning(void){
506     printf("Start scanning...\n");
507     gap_inquiry_start(A2DP_SOURCE_DEMO_INQUIRY_DURATION_1280MS);
508     scan_active = true;
509 }
510 
511 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
512     UNUSED(channel);
513     UNUSED(size);
514     if (packet_type != HCI_EVENT_PACKET) return;
515     uint8_t status;
516     UNUSED(status);
517 
518     bd_addr_t address;
519     uint32_t cod;
520 
521     // Service Class: Rendering | Audio, Major Device Class: Audio
522     const uint32_t bluetooth_speaker_cod = 0x200000 | 0x040000 | 0x000400;
523 
524     switch (hci_event_packet_get_type(packet)){
525 #ifndef HAVE_BTSTACK_STDIN
526         case  BTSTACK_EVENT_STATE:
527             if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) return;
528             a2dp_source_demo_start_scanning();
529             break;
530 #endif
531         case HCI_EVENT_PIN_CODE_REQUEST:
532             printf("Pin code request - using '0000'\n");
533             hci_event_pin_code_request_get_bd_addr(packet, address);
534             gap_pin_code_response(address, "0000");
535             break;
536         case GAP_EVENT_INQUIRY_RESULT:
537             gap_event_inquiry_result_get_bd_addr(packet, address);
538             // print info
539             printf("Device found: %s ",  bd_addr_to_str(address));
540             cod = gap_event_inquiry_result_get_class_of_device(packet);
541             printf("with COD: %06" PRIx32, cod);
542             if (gap_event_inquiry_result_get_rssi_available(packet)){
543                 printf(", rssi %d dBm", (int8_t) gap_event_inquiry_result_get_rssi(packet));
544             }
545             if (gap_event_inquiry_result_get_name_available(packet)){
546                 char name_buffer[240];
547                 int name_len = gap_event_inquiry_result_get_name_len(packet);
548                 memcpy(name_buffer, gap_event_inquiry_result_get_name(packet), name_len);
549                 name_buffer[name_len] = 0;
550                 printf(", name '%s'", name_buffer);
551             }
552             printf("\n");
553             if ((cod & bluetooth_speaker_cod) == bluetooth_speaker_cod){
554                 memcpy(device_addr, address, 6);
555                 printf("Bluetooth speaker detected, trying to connect to %s...\n", bd_addr_to_str(device_addr));
556                 scan_active = false;
557                 gap_inquiry_stop();
558                 a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
559             }
560             break;
561         case GAP_EVENT_INQUIRY_COMPLETE:
562             if (scan_active){
563                 printf("No Bluetooth speakers found, scanning again...\n");
564                 gap_inquiry_start(A2DP_SOURCE_DEMO_INQUIRY_DURATION_1280MS);
565             }
566             break;
567         default:
568             break;
569     }
570 }
571 
572 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
573     UNUSED(channel);
574     UNUSED(size);
575     uint8_t status;
576     uint8_t local_seid;
577     bd_addr_t address;
578     uint16_t cid;
579 
580     avdtp_channel_mode_t channel_mode;
581     uint8_t allocation_method;
582 
583     if (packet_type != HCI_EVENT_PACKET) return;
584     if (hci_event_packet_get_type(packet) != HCI_EVENT_A2DP_META) return;
585 
586     switch (hci_event_a2dp_meta_get_subevent_code(packet)){
587         case A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
588             a2dp_subevent_signaling_connection_established_get_bd_addr(packet, address);
589             cid = a2dp_subevent_signaling_connection_established_get_a2dp_cid(packet);
590             status = a2dp_subevent_signaling_connection_established_get_status(packet);
591 
592             if (status != ERROR_CODE_SUCCESS){
593                 printf("A2DP Source: Connection failed, status 0x%02x, cid 0x%02x, a2dp_cid 0x%02x \n", status, cid, media_tracker.a2dp_cid);
594                 media_tracker.a2dp_cid = 0;
595                 break;
596             }
597             media_tracker.a2dp_cid = cid;
598             media_tracker.volume = 32;
599 
600             printf("A2DP Source: Connected to address %s, a2dp cid 0x%02x, local seid 0x%02x.\n", bd_addr_to_str(address), media_tracker.a2dp_cid, media_tracker.local_seid);
601             break;
602 
603          case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
604             cid  = avdtp_subevent_signaling_media_codec_sbc_configuration_get_avdtp_cid(packet);
605             if (cid != media_tracker.a2dp_cid) return;
606 
607             media_tracker.remote_seid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet);
608 
609             sbc_configuration.reconfigure = a2dp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
610             sbc_configuration.num_channels = a2dp_subevent_signaling_media_codec_sbc_configuration_get_num_channels(packet);
611             sbc_configuration.sampling_frequency = a2dp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
612             sbc_configuration.block_length = a2dp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
613             sbc_configuration.subbands = a2dp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
614             sbc_configuration.min_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
615             sbc_configuration.max_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
616 
617             channel_mode = (avdtp_channel_mode_t) a2dp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
618             allocation_method = a2dp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
619 
620             printf("A2DP Source: Received SBC codec configuration, sampling frequency %u, a2dp_cid 0x%02x, local seid 0x%02x, remote seid 0x%02x.\n",
621                 sbc_configuration.sampling_frequency, cid,
622                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_local_seid(packet),
623                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet));
624 
625             // Adapt Bluetooth spec definition to SBC Encoder expected input
626             sbc_configuration.allocation_method = (btstack_sbc_allocation_method_t)(allocation_method - 1);
627             switch (channel_mode){
628                 case AVDTP_CHANNEL_MODE_JOINT_STEREO:
629                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
630                     break;
631                 case AVDTP_CHANNEL_MODE_STEREO:
632                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_STEREO;
633                     break;
634                 case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
635                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
636                     break;
637                 case AVDTP_CHANNEL_MODE_MONO:
638                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_MONO;
639                     break;
640                 default:
641                     btstack_assert(false);
642                     break;
643             }
644             dump_sbc_configuration(&sbc_configuration);
645 
646             btstack_sbc_encoder_init(&sbc_encoder_state, SBC_MODE_STANDARD,
647                 sbc_configuration.block_length, sbc_configuration.subbands,
648                 sbc_configuration.allocation_method, sbc_configuration.sampling_frequency,
649                 sbc_configuration.max_bitpool_value,
650                 sbc_configuration.channel_mode);
651             break;
652         }
653 
654         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
655             printf("A2DP Source: remote supports delay report, remote seid %d\n",
656                 avdtp_subevent_signaling_delay_reporting_capability_get_remote_seid(packet));
657             break;
658         case A2DP_SUBEVENT_SIGNALING_CAPABILITIES_DONE:
659             printf("A2DP Source: All capabilities reported, remote seid %d\n",
660                 avdtp_subevent_signaling_capabilities_done_get_remote_seid(packet));
661             break;
662 
663         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORT:
664             printf("A2DP Source: Received delay report of %d.%0d ms, local seid %d\n",
665                 avdtp_subevent_signaling_delay_report_get_delay_100us(packet)/10, avdtp_subevent_signaling_delay_report_get_delay_100us(packet)%10,
666                 avdtp_subevent_signaling_delay_report_get_local_seid(packet));
667             break;
668 
669         case A2DP_SUBEVENT_STREAM_ESTABLISHED:
670             a2dp_subevent_stream_established_get_bd_addr(packet, address);
671             status = a2dp_subevent_stream_established_get_status(packet);
672             if (status != ERROR_CODE_SUCCESS){
673                 printf("A2DP Source: Stream failed, status 0x%02x.\n", status);
674                 break;
675             }
676 
677             local_seid = a2dp_subevent_stream_established_get_local_seid(packet);
678             cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
679 
680             printf("A2DP Source: Stream established a2dp_cid 0x%02x, local_seid 0x%02x, remote_seid 0x%02x\n", cid, local_seid, a2dp_subevent_stream_established_get_remote_seid(packet));
681 
682             a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
683             media_tracker.stream_opened = 1;
684             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
685             break;
686 
687         case A2DP_SUBEVENT_STREAM_RECONFIGURED:
688             status = a2dp_subevent_stream_reconfigured_get_status(packet);
689             local_seid = a2dp_subevent_stream_reconfigured_get_local_seid(packet);
690             cid = a2dp_subevent_stream_reconfigured_get_a2dp_cid(packet);
691 
692             if (status != ERROR_CODE_SUCCESS){
693                 printf("A2DP Source: Stream reconfiguration failed, status 0x%02x\n", status);
694                 break;
695             }
696 
697             printf("A2DP Source: Stream reconfigured a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
698             a2dp_demo_hexcmod_configure_sample_rate(new_sample_rate);
699             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
700             break;
701 
702         case A2DP_SUBEVENT_STREAM_STARTED:
703             local_seid = a2dp_subevent_stream_started_get_local_seid(packet);
704             cid = a2dp_subevent_stream_started_get_a2dp_cid(packet);
705 
706             play_info.status = AVRCP_PLAYBACK_STATUS_PLAYING;
707             if (media_tracker.avrcp_cid){
708                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
709                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PLAYING);
710             }
711             a2dp_demo_timer_start(&media_tracker);
712             printf("A2DP Source: Stream started, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
713             break;
714 
715         case A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
716             local_seid = a2dp_subevent_streaming_can_send_media_packet_now_get_local_seid(packet);
717             cid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_a2dp_cid(packet);
718             a2dp_demo_send_media_packet();
719             break;
720 
721         case A2DP_SUBEVENT_STREAM_SUSPENDED:
722             local_seid = a2dp_subevent_stream_suspended_get_local_seid(packet);
723             cid = a2dp_subevent_stream_suspended_get_a2dp_cid(packet);
724 
725             play_info.status = AVRCP_PLAYBACK_STATUS_PAUSED;
726             if (media_tracker.avrcp_cid){
727                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PAUSED);
728             }
729             printf("A2DP Source: Stream paused, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
730 
731             a2dp_demo_timer_stop(&media_tracker);
732             break;
733 
734         case A2DP_SUBEVENT_STREAM_RELEASED:
735             play_info.status = AVRCP_PLAYBACK_STATUS_STOPPED;
736             cid = a2dp_subevent_stream_released_get_a2dp_cid(packet);
737             local_seid = a2dp_subevent_stream_released_get_local_seid(packet);
738 
739             printf("A2DP Source: Stream released, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
740 
741             if (cid == media_tracker.a2dp_cid) {
742                 media_tracker.stream_opened = 0;
743                 printf("A2DP Source: Stream released.\n");
744             }
745             if (media_tracker.avrcp_cid){
746                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
747                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_STOPPED);
748             }
749             a2dp_demo_timer_stop(&media_tracker);
750             break;
751         case A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
752             cid = a2dp_subevent_signaling_connection_released_get_a2dp_cid(packet);
753             if (cid == media_tracker.a2dp_cid) {
754                 media_tracker.avrcp_cid = 0;
755                 media_tracker.a2dp_cid = 0;
756                 printf("A2DP Source: Signaling released.\n\n");
757             }
758             break;
759         default:
760             break;
761     }
762 }
763 
764 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
765     UNUSED(channel);
766     UNUSED(size);
767     bd_addr_t event_addr;
768     uint16_t local_cid;
769     uint8_t  status = ERROR_CODE_SUCCESS;
770 
771     if (packet_type != HCI_EVENT_PACKET) return;
772     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
773 
774     switch (packet[2]){
775         case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED:
776             local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
777             status = avrcp_subevent_connection_established_get_status(packet);
778             if (status != ERROR_CODE_SUCCESS){
779                 printf("AVRCP: Connection failed, local cid 0x%02x, status 0x%02x\n", local_cid, status);
780                 return;
781             }
782             media_tracker.avrcp_cid = local_cid;
783             avrcp_subevent_connection_established_get_bd_addr(packet, event_addr);
784 
785             printf("AVRCP: Channel to %s successfully opened, avrcp_cid 0x%02x\n", bd_addr_to_str(event_addr), media_tracker.avrcp_cid);
786 
787             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED);
788             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
789             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED);
790             avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
791 
792             printf("Enable Volume Change notification\n");
793             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED);
794             printf("Enable Battery Status Change notification\n");
795             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_BATT_STATUS_CHANGED);
796             return;
797 
798         case AVRCP_SUBEVENT_CONNECTION_RELEASED:
799             printf("AVRCP Target: Disconnected, avrcp_cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
800             media_tracker.avrcp_cid = 0;
801             return;
802         default:
803             break;
804     }
805 
806     if (status != ERROR_CODE_SUCCESS){
807         printf("Responding to event 0x%02x failed, status 0x%02x\n", packet[2], status);
808     }
809 }
810 
811 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
812     UNUSED(channel);
813     UNUSED(size);
814     uint8_t  status = ERROR_CODE_SUCCESS;
815 
816     if (packet_type != HCI_EVENT_PACKET) return;
817     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
818 
819     bool button_pressed;
820     char const * button_state;
821     avrcp_operation_id_t operation_id;
822 
823     switch (packet[2]){
824         case AVRCP_SUBEVENT_PLAY_STATUS_QUERY:
825             status = avrcp_target_play_status(media_tracker.avrcp_cid, play_info.song_length_ms, play_info.song_position_ms, play_info.status);
826             break;
827         // case AVRCP_SUBEVENT_NOW_PLAYING_INFO_QUERY:
828         //     status = avrcp_target_now_playing_info(avrcp_cid);
829         //     break;
830         case AVRCP_SUBEVENT_OPERATION:
831             operation_id = avrcp_subevent_operation_get_operation_id(packet);
832             button_pressed = avrcp_subevent_operation_get_button_pressed(packet) > 0;
833             button_state = button_pressed ? "PRESS" : "RELEASE";
834 
835             printf("AVRCP Target: operation %s (%s)\n", avrcp_operation2str(operation_id), button_state);
836 
837             if (!button_pressed){
838                 break;
839             }
840             switch (operation_id) {
841                 case AVRCP_OPERATION_ID_PLAY:
842                     status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
843                     break;
844                 case AVRCP_OPERATION_ID_PAUSE:
845                     status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
846                     break;
847                 case AVRCP_OPERATION_ID_STOP:
848                     status = a2dp_source_disconnect(media_tracker.a2dp_cid);
849                     break;
850                 default:
851                     break;
852             }
853             break;
854         default:
855             break;
856     }
857 
858     if (status != ERROR_CODE_SUCCESS){
859         printf("Responding to event 0x%02x failed, status 0x%02x\n", packet[2], status);
860     }
861 }
862 
863 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
864     UNUSED(channel);
865     UNUSED(size);
866 
867     if (packet_type != HCI_EVENT_PACKET) return;
868     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
869     if (!media_tracker.avrcp_cid) return;
870 
871     switch (packet[2]){
872         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
873             printf("AVRCP Controller: Notification Absolute Volume %d %%\n", avrcp_subevent_notification_volume_changed_get_absolute_volume(packet) * 100 / 127);
874             break;
875         case AVRCP_SUBEVENT_NOTIFICATION_EVENT_BATT_STATUS_CHANGED:
876             // see avrcp_battery_status_t
877             printf("AVRCP Controller: Notification Battery Status 0x%02x\n", avrcp_subevent_notification_event_batt_status_changed_get_battery_status(packet));
878             break;
879         case AVRCP_SUBEVENT_NOTIFICATION_STATE:
880             printf("AVRCP Controller: Notification %s - %s\n",
881                 avrcp_event2str(avrcp_subevent_notification_state_get_event_id(packet)),
882                 avrcp_subevent_notification_state_get_enabled(packet) != 0 ? "enabled" : "disabled");
883             break;
884         default:
885             break;
886     }
887 }
888 
889 #ifdef HAVE_BTSTACK_STDIN
890 static void show_usage(void){
891     bd_addr_t      iut_address;
892     gap_local_bd_addr(iut_address);
893     printf("\n--- Bluetooth  A2DP Source/AVRCP Demo %s ---\n", bd_addr_to_str(iut_address));
894     printf("a      - Scan for Bluetooth speaker and connect\n");
895     printf("b      - A2DP Source create connection to addr %s\n", device_addr_string);
896     printf("B      - A2DP Source disconnect\n");
897     printf("c      - AVRCP create connection to addr %s\n", device_addr_string);
898     printf("C      - AVRCP disconnect\n");
899     printf("D      - delete all link keys\n");
900 
901     printf("x      - start streaming sine\n");
902     if (hxcmod_initialized){
903         printf("z      - start streaming '%s'\n", mod_name);
904     }
905     printf("p      - pause streaming\n");
906     printf("w      - reconfigure stream for 44100 Hz\n");
907     printf("e      - reconfigure stream for 48000 Hz\n");
908     printf("t      - volume up\n");
909     printf("T      - volume down\n");
910     printf("v      - volume up (via set absolute volume)\n");
911     printf("V      - volume down (via set absolute volume)\n");
912 
913     printf("---\n");
914 }
915 
916 static void stdin_process(char cmd){
917     uint8_t status = ERROR_CODE_SUCCESS;
918     switch (cmd){
919         case 'a':
920             a2dp_source_demo_start_scanning();
921             break;
922         case 'b':
923             status = a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
924             printf("%c - Create A2DP Source connection to addr %s, cid 0x%02x.\n", cmd, bd_addr_to_str(device_addr), media_tracker.a2dp_cid);
925             break;
926         case 'B':
927             printf("%c - A2DP Source Disconnect from cid 0x%2x\n", cmd, media_tracker.a2dp_cid);
928             status = a2dp_source_disconnect(media_tracker.a2dp_cid);
929             break;
930         case 'c':
931             printf("%c - Create AVRCP connection to addr %s.\n", cmd, bd_addr_to_str(device_addr));
932             status = avrcp_connect(device_addr, &media_tracker.avrcp_cid);
933             break;
934         case 'C':
935             printf("%c - AVRCP disconnect\n", cmd);
936             status = avrcp_disconnect(media_tracker.avrcp_cid);
937             break;
938         case 'D':
939             printf("Deleting all link keys\n");
940             gap_delete_all_link_keys();
941             break;
942         case '\n':
943         case '\r':
944             break;
945 
946         case 't':
947             printf(" - volume up\n");
948             status = avrcp_controller_volume_up(media_tracker.avrcp_cid);
949             break;
950         case 'T':
951             printf(" - volume down\n");
952             status = avrcp_controller_volume_down(media_tracker.avrcp_cid);
953             break;
954 
955         case 'v':
956             if (media_tracker.volume > 117){
957                 media_tracker.volume = 127;
958             } else {
959                 media_tracker.volume += 10;
960             }
961             printf(" - volume up (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
962             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
963             break;
964         case 'V':
965             if (media_tracker.volume < 10){
966                 media_tracker.volume = 0;
967             } else {
968                 media_tracker.volume -= 10;
969             }
970             printf(" - volume down (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
971             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
972             break;
973 
974         case 'x':
975             if (media_tracker.avrcp_cid){
976                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
977             }
978             printf("%c - Play sine.\n", cmd);
979             data_source = STREAM_SINE;
980             if (!media_tracker.stream_opened) break;
981             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
982             break;
983         case 'z':
984             if (media_tracker.avrcp_cid){
985                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
986             }
987             printf("%c - Play mod.\n", cmd);
988             data_source = STREAM_MOD;
989             if (!media_tracker.stream_opened) break;
990             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
991             break;
992 
993         case 'p':
994             if (!media_tracker.stream_opened) break;
995             printf("%c - Pause stream.\n", cmd);
996             status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
997             break;
998 
999         case 'w':
1000             if (!media_tracker.stream_opened) break;
1001             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
1002                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
1003                 break;
1004             }
1005             new_sample_rate = 44100;
1006             if (current_sample_rate == new_sample_rate){
1007                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
1008             } else {
1009                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
1010                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
1011             }
1012             break;
1013 
1014         case 'e':
1015             if (!media_tracker.stream_opened) break;
1016             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
1017                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
1018                 break;
1019             }
1020             new_sample_rate = 48000;
1021             if (current_sample_rate == new_sample_rate){
1022                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
1023             } else {
1024                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
1025                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
1026             }
1027             break;
1028 
1029         default:
1030             show_usage();
1031             return;
1032     }
1033     if (status != ERROR_CODE_SUCCESS){
1034         printf("Could not perform command \'%c\', status 0x%02x\n", cmd, status);
1035     }
1036 }
1037 #endif
1038 
1039 
1040 int btstack_main(int argc, const char * argv[]);
1041 int btstack_main(int argc, const char * argv[]){
1042     (void)argc;
1043     (void)argv;
1044 
1045     int err = a2dp_source_and_avrcp_services_init();
1046     if (err) return err;
1047     // turn on!
1048     hci_power_control(HCI_POWER_ON);
1049     return 0;
1050 }
1051 /* EXAMPLE_END */
1052