xref: /btstack/example/a2dp_sink_demo.c (revision a8d51f092f1b660d0f6921369ad2bc3f9368296c)
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 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__ "a2dp_sink_demo.c"
39 
40 /*
41  * a2dp_sink_demo.c
42  */
43 
44 // *****************************************************************************
45 /* EXAMPLE_START(a2dp_sink_demo): A2DP Sink - Receive Audio Stream and Control Playback
46  *
47  * @text This A2DP Sink example demonstrates how to use the A2DP Sink service to
48  * receive an audio data stream from a remote A2DP Source device. In addition,
49  * the AVRCP Controller is used to get information on currently played media,
50  * such are title, artist and album, as well as to control the playback,
51  * i.e. to play, stop, repeat, etc. If HAVE_BTSTACK_STDIN is set, press SPACE on
52  * the console to show the available AVDTP and AVRCP commands.
53  *
54  * @text To test with a remote device, e.g. a mobile phone,
55  * pair from the remote device with the demo, then start playing music on the remote device.
56  * Alternatively, set the device_addr_string to the Bluetooth address of your
57  * remote device in the code, and call connect from the UI.
58  *
59  * @text For more info on BTstack audio, see our blog post
60  * [A2DP Sink and Source on STM32 F4 Discovery Board](http://bluekitchen-gmbh.com/a2dp-sink-and-source-on-stm32-f4-discovery-board/).
61  *
62  */
63 // *****************************************************************************
64 
65 #include <inttypes.h>
66 #include <stdint.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <string.h>
70 
71 #include "btstack.h"
72 #include "btstack_resample.h"
73 
74 //#define AVRCP_BROWSING_ENABLED
75 
76 // if volume control not supported by btstack_audio_sink, you can try to disable volume change notification
77 // to force the A2DP Source to reduce volume by attenuating the audio stream
78 #define SUPPORT_VOLUME_CHANGE_NOTIFICATION
79 
80 #ifdef HAVE_BTSTACK_STDIN
81 #include "btstack_stdin.h"
82 #endif
83 
84 #include "btstack_ring_buffer.h"
85 
86 #ifdef HAVE_POSIX_FILE_IO
87 #include "wav_util.h"
88 #define STORE_TO_SBC_FILE
89 #define STORE_TO_WAV_FILE
90 #endif
91 
92 #define NUM_CHANNELS 2
93 #define BYTES_PER_FRAME     (2*NUM_CHANNELS)
94 #define MAX_SBC_FRAME_SIZE 120
95 
96 // SBC Decoder for WAV file or live playback
97 static btstack_sbc_decoder_state_t state;
98 static btstack_sbc_mode_t mode = SBC_MODE_STANDARD;
99 
100 // ring buffer for SBC Frames
101 // below 30: add samples, 30-40: fine, above 40: drop samples
102 #define OPTIMAL_FRAMES_MIN 30
103 #define OPTIMAL_FRAMES_MAX 40
104 #define ADDITIONAL_FRAMES  20
105 static uint8_t sbc_frame_storage[(OPTIMAL_FRAMES_MAX + ADDITIONAL_FRAMES) * MAX_SBC_FRAME_SIZE];
106 static btstack_ring_buffer_t sbc_frame_ring_buffer;
107 static unsigned int sbc_frame_size;
108 
109 // rest buffer for not fully used sbc frames, with additional frames for resampling
110 static uint8_t decoded_audio_storage[(128+16) * BYTES_PER_FRAME];
111 static btstack_ring_buffer_t decoded_audio_ring_buffer;
112 
113 static int audio_stream_started;
114 
115 // temp storage of lower-layer request
116 static int16_t * request_buffer;
117 static int       request_frames;
118 
119 #define STORE_FROM_PLAYBACK
120 
121 // WAV File
122 #ifdef STORE_TO_WAV_FILE
123 static uint32_t audio_frame_count = 0;
124 static char * wav_filename = "av2dp_sink_demo.wav";
125 #endif
126 
127 #ifdef STORE_TO_SBC_FILE
128 static FILE * sbc_file;
129 static char * sbc_filename = "av2dp_sink_demo.sbc";
130 #endif
131 
132 typedef struct {
133     int reconfigure;
134     int num_channels;
135     int sampling_frequency;
136     int channel_mode;
137     int block_length;
138     int subbands;
139     int allocation_method;
140     int min_bitpool_value;
141     int max_bitpool_value;
142     int frames_per_buffer;
143 } avdtp_media_codec_configuration_sbc_t;
144 
145 static avdtp_media_codec_configuration_sbc_t sbc_configuration;
146 static int volume_percentage = 0;
147 
148 #ifdef SUPPORT_VOLUME_CHANGE_NOTIFICATION
149 static uint8_t events_num = 3;
150 static uint8_t events[] = {
151     AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED,
152     AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED,
153     AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED
154 };
155 #endif
156 
157 static uint8_t companies_num = 1;
158 static uint8_t companies[] = {
159     0x00, 0x19, 0x58 //BT SIG registered CompanyID
160 };
161 
162 #ifdef HAVE_BTSTACK_STDIN
163 // pts:
164 static const char * device_addr_string = "6C:72:E7:10:22:EE";
165 // mac 2013:  static const char * device_addr_string = "84:38:35:65:d1:15";
166 // iPhone 5S: static const char * device_addr_string = "54:E4:3A:26:A2:39";
167 static bd_addr_t device_addr;
168 #endif
169 
170 static btstack_packet_callback_registration_t hci_event_callback_registration;
171 
172 static uint8_t  sdp_avdtp_sink_service_buffer[150];
173 static uint8_t  sdp_avrcp_target_service_buffer[150];
174 static uint8_t  sdp_avrcp_controller_service_buffer[200];
175 static uint8_t  device_id_sdp_service_buffer[100];
176 
177 static uint16_t a2dp_cid = 0;
178 static uint8_t  a2dp_local_seid = 0;
179 
180 static uint16_t avrcp_cid = 0;
181 static uint8_t  avrcp_connected = 0;
182 static uint8_t  avrcp_subevent_value[100];
183 
184 static uint8_t media_sbc_codec_capabilities[] = {
185     0xFF,//(AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
186     0xFF,//(AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
187     2, 53
188 };
189 
190 static uint8_t media_sbc_codec_configuration[] = {
191     (AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
192     (AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
193     2, 53
194 };
195 
196 static int media_initialized = 0;
197 static btstack_resample_t resample_instance;
198 
199 /* @section Main Application Setup
200  *
201  * @text The Listing MainConfiguration shows how to setup AD2P Sink and AVRCP services.
202  * Besides calling init() method for each service, you'll also need to register several packet handlers:
203  * - hci_packet_handler - handles legacy pairing, here by using fixed '0000' pin code.
204  * - a2dp_sink_packet_handler - handles events on stream connection status (established, released), the media codec configuration, and, the status of the stream itself (opened, paused, stopped).
205  * - handle_l2cap_media_data_packet - used to receive streaming data. If STORE_TO_WAV_FILE directive (check btstack_config.h) is used, the SBC decoder will be used to decode the SBC data into PCM frames. The resulting PCM frames are then processed in the SBC Decoder callback.
206  * - avrcp_packet_handler - receives connect/disconnect event.
207  * - avrcp_controller_packet_handler - receives answers for sent AVRCP commands.
208  * - avrcp_target_packet_handler - receives AVRCP commands, and registered notifications.
209  * - 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.
210  *
211  * @text To announce A2DP Sink and AVRCP services, you need to create corresponding
212  * SDP records and register them with the SDP service.
213  *
214  * @text Note, currently only the SBC codec is supported.
215  * If you want to store the audio data in a file, you'll need to define STORE_TO_WAV_FILE.
216  * If STORE_TO_WAV_FILE directive is defined, the SBC decoder needs to get initialized when a2dp_sink_packet_handler receives event A2DP_SUBEVENT_STREAM_STARTED.
217  * The initialization of the SBC decoder requires a callback that handles PCM data:
218  * - handle_pcm_data - handles PCM audio frames. Here, they are stored a in wav file if STORE_TO_WAV_FILE is defined, and/or played using the audio library.
219  */
220 
221 /* LISTING_START(MainConfiguration): Setup Audio Sink and AVRCP services */
222 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
223 static void a2dp_sink_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t event_size);
224 static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16_t size);
225 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
226 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
227 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
228 #ifdef HAVE_BTSTACK_STDIN
229 static void stdin_process(char cmd);
230 #endif
231 
232 static int a2dp_and_avrcp_setup(void){
233     l2cap_init();
234     // Initialize AVDTP Sink
235     a2dp_sink_init();
236     a2dp_sink_register_packet_handler(&a2dp_sink_packet_handler);
237     a2dp_sink_register_media_handler(&handle_l2cap_media_data_packet);
238 
239     // Create stream endpoint
240     avdtp_stream_endpoint_t * local_stream_endpoint = a2dp_sink_create_stream_endpoint(AVDTP_AUDIO,
241         AVDTP_CODEC_SBC, media_sbc_codec_capabilities, sizeof(media_sbc_codec_capabilities),
242         media_sbc_codec_configuration, sizeof(media_sbc_codec_configuration));
243     if (!local_stream_endpoint){
244         printf("A2DP Sink: not enough memory to create local stream endpoint\n");
245         return 1;
246     }
247 
248     // Store stream enpoint's SEP ID, as it is used by A2DP API to indentify the stream endpoint
249     a2dp_local_seid = avdtp_local_seid(local_stream_endpoint);
250 
251     // Initialize AVRCP service
252     avrcp_init();
253     avrcp_register_packet_handler(&avrcp_packet_handler);
254 
255     // Initialize AVRCP Controller
256     avrcp_controller_init();
257     avrcp_controller_register_packet_handler(&avrcp_controller_packet_handler);
258 
259      // Initialize AVRCP Target
260     avrcp_target_init();
261     avrcp_target_register_packet_handler(&avrcp_target_packet_handler);
262 
263     // Initialize SDP
264     sdp_init();
265 
266     // Create A2DP Sink service record and register it with SDP
267     memset(sdp_avdtp_sink_service_buffer, 0, sizeof(sdp_avdtp_sink_service_buffer));
268     a2dp_sink_create_sdp_record(sdp_avdtp_sink_service_buffer, 0x10001, AVDTP_SINK_FEATURE_MASK_HEADPHONE, NULL, NULL);
269     sdp_register_service(sdp_avdtp_sink_service_buffer);
270 
271     // Create AVRCP Controller service record and register it with SDP
272     memset(sdp_avrcp_controller_service_buffer, 0, sizeof(sdp_avrcp_controller_service_buffer));
273     uint16_t controller_supported_features = AVRCP_FEATURE_MASK_CATEGORY_PLAYER_OR_RECORDER;
274 #ifdef AVRCP_BROWSING_ENABLED
275     controller_supported_features |= AVRCP_FEATURE_MASK_BROWSING;
276 #endif
277     avrcp_controller_create_sdp_record(sdp_avrcp_controller_service_buffer, 0x10002, controller_supported_features, NULL, NULL);
278     sdp_register_service(sdp_avrcp_controller_service_buffer);
279 
280     // Create AVRCP Target service record and register it with SDP
281     memset(sdp_avrcp_target_service_buffer, 0, sizeof(sdp_avrcp_target_service_buffer));
282     uint16_t target_supported_features = AVRCP_FEATURE_MASK_CATEGORY_MONITOR_OR_AMPLIFIER;
283     avrcp_target_create_sdp_record(sdp_avrcp_target_service_buffer, 0x10003, target_supported_features, NULL, NULL);
284     sdp_register_service(sdp_avrcp_target_service_buffer);
285 
286     // Create Device ID (PnP) service record and register it with SDP
287     memset(device_id_sdp_service_buffer, 0, sizeof(device_id_sdp_service_buffer));
288     device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10004, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1);
289     sdp_register_service(device_id_sdp_service_buffer);
290 
291     // Set local name with a template Bluetooth address, that will be automatically
292     // replaced with a actual address once it is available, i.e. when BTstack boots
293     // up and starts talking to a Bluetooth module.
294     gap_set_local_name("A2DP Sink Demo 00:00:00:00:00:00");
295     gap_discoverable_control(1);
296     gap_set_class_of_device(0x200408);
297 
298     // Register for HCI events
299     hci_event_callback_registration.callback = &hci_packet_handler;
300     hci_add_event_handler(&hci_event_callback_registration);
301 
302 #ifdef HAVE_POSIX_FILE_IO
303     if (!btstack_audio_sink_get_instance()){
304         printf("No audio playback.\n");
305     } else {
306         printf("Audio playback supported.\n");
307     }
308 #ifdef STORE_TO_WAV_FILE
309    printf("Audio will be stored to \'%s\' file.\n",  wav_filename);
310 #endif
311 #endif
312     return 0;
313 }
314 /* LISTING_END */
315 
316 static void playback_handler(int16_t * buffer, uint16_t num_audio_frames){
317 
318 #ifdef STORE_TO_WAV_FILE
319     int       wav_samples = num_audio_frames * NUM_CHANNELS;
320     int16_t * wav_buffer  = buffer;
321 #endif
322 
323     // called from lower-layer but guaranteed to be on main thread
324     if (sbc_frame_size == 0){
325         memset(buffer, 0, num_audio_frames * BYTES_PER_FRAME);
326         return;
327     }
328 
329     // first fill from resampled audio
330     uint32_t bytes_read;
331     btstack_ring_buffer_read(&decoded_audio_ring_buffer, (uint8_t *) buffer, num_audio_frames * BYTES_PER_FRAME, &bytes_read);
332     buffer          += bytes_read / NUM_CHANNELS;
333     num_audio_frames   -= bytes_read / BYTES_PER_FRAME;
334 
335     // then start decoding sbc frames using request_* globals
336     request_buffer = buffer;
337     request_frames = num_audio_frames;
338     while (request_frames && btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer) >= sbc_frame_size){
339         // decode frame
340         uint8_t sbc_frame[MAX_SBC_FRAME_SIZE];
341         btstack_ring_buffer_read(&sbc_frame_ring_buffer, sbc_frame, sbc_frame_size, &bytes_read);
342         btstack_sbc_decoder_process_data(&state, 0, sbc_frame, sbc_frame_size);
343     }
344 
345 #ifdef STORE_TO_WAV_FILE
346     audio_frame_count += num_audio_frames;
347     wav_writer_write_int16(wav_samples, wav_buffer);
348 #endif
349 }
350 
351 static void handle_pcm_data(int16_t * data, int num_audio_frames, int num_channels, int sample_rate, void * context){
352     UNUSED(sample_rate);
353     UNUSED(context);
354     UNUSED(num_channels);   // must be stereo == 2
355 
356     const btstack_audio_sink_t * audio_sink = btstack_audio_sink_get_instance();
357     if (!audio_sink){
358 #ifdef STORE_TO_WAV_FILE
359         audio_frame_count += num_audio_frames;
360         wav_writer_write_int16(num_audio_frames * NUM_CHANNELS, data);
361 #endif
362         return;
363     }
364 
365     // resample into request buffer - add some additional space for resampling
366     int16_t  output_buffer[(128+16) * NUM_CHANNELS]; // 16 * 8 * 2
367     uint32_t resampled_frames = btstack_resample_block(&resample_instance, data, num_audio_frames, output_buffer);
368 
369     // store data in btstack_audio buffer first
370     int frames_to_copy = btstack_min(resampled_frames, request_frames);
371     memcpy(request_buffer, output_buffer, frames_to_copy * BYTES_PER_FRAME);
372     request_frames  -= frames_to_copy;
373     request_buffer  += frames_to_copy * NUM_CHANNELS;
374 
375     // and rest in ring buffer
376     int frames_to_store = resampled_frames - frames_to_copy;
377     if (frames_to_store){
378         int status = btstack_ring_buffer_write(&decoded_audio_ring_buffer, (uint8_t *)&output_buffer[frames_to_copy * NUM_CHANNELS], frames_to_store * BYTES_PER_FRAME);
379         if (status){
380             printf("Error storing samples in PCM ring buffer!!!\n");
381         }
382     }
383 }
384 
385 static int media_processing_init(avdtp_media_codec_configuration_sbc_t configuration){
386     if (media_initialized) return 0;
387 
388     btstack_sbc_decoder_init(&state, mode, handle_pcm_data, NULL);
389 
390 #ifdef STORE_TO_WAV_FILE
391     wav_writer_open(wav_filename, configuration.num_channels, configuration.sampling_frequency);
392 #endif
393 
394 #ifdef STORE_TO_SBC_FILE
395    sbc_file = fopen(sbc_filename, "wb");
396 #endif
397 
398     btstack_ring_buffer_init(&sbc_frame_ring_buffer, sbc_frame_storage, sizeof(sbc_frame_storage));
399     btstack_ring_buffer_init(&decoded_audio_ring_buffer, decoded_audio_storage, sizeof(decoded_audio_storage));
400     btstack_resample_init(&resample_instance, configuration.num_channels);
401 
402     // setup audio playback
403     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
404     if (audio){
405         audio->init(NUM_CHANNELS, configuration.sampling_frequency, &playback_handler);
406     }
407 
408     audio_stream_started = 0;
409     media_initialized = 1;
410     return 0;
411 }
412 
413 static void media_processing_start(void){
414     if (!media_initialized) return;
415     // setup audio playback
416     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
417     if (audio){
418         audio->start_stream();
419     }
420     audio_stream_started = 1;
421 }
422 
423 static void media_processing_pause(void){
424     if (!media_initialized) return;
425     // stop audio playback
426     audio_stream_started = 0;
427     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
428     if (audio){
429         audio->stop_stream();
430     }
431 }
432 
433 static void media_processing_close(void){
434     if (!media_initialized) return;
435     media_initialized = 0;
436     audio_stream_started = 0;
437     sbc_frame_size = 0;
438 
439 #ifdef STORE_TO_WAV_FILE
440     wav_writer_close();
441     uint32_t total_frames_nr = state.good_frames_nr + state.bad_frames_nr + state.zero_frames_nr;
442 
443     printf("WAV Writer: Decoding done. Processed %u SBC frames:\n - %d good\n - %d bad\n", total_frames_nr, state.good_frames_nr, total_frames_nr - state.good_frames_nr);
444     printf("WAV Writer: Wrote %u audio frames to wav file: %s\n", audio_frame_count, wav_filename);
445 #endif
446 
447 #ifdef STORE_TO_SBC_FILE
448     fclose(sbc_file);
449 #endif
450 
451     // stop audio playback
452     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
453     if (audio){
454         printf("close stream\n");
455         audio->close();
456     }
457 }
458 
459 /* @section Handle Media Data Packet
460  *
461  * @text Here the audio data, are received through the handle_l2cap_media_data_packet callback.
462  * Currently, only the SBC media codec is supported. Hence, the media data consists of the media packet header and the SBC packet.
463  * The SBC frame will be stored in a ring buffer for later processing (instead of decoding it to PCM right away which would require a much larger buffer).
464  * If the audio stream wasn't started already and there are enough SBC frames in the ring buffer, start playback.
465  */
466 
467 static int read_media_data_header(uint8_t * packet, int size, int * offset, avdtp_media_packet_header_t * media_header);
468 static int read_sbc_header(uint8_t * packet, int size, int * offset, avdtp_sbc_codec_header_t * sbc_header);
469 
470 static void handle_l2cap_media_data_packet(uint8_t seid, uint8_t *packet, uint16_t size){
471     UNUSED(seid);
472     int pos = 0;
473 
474     avdtp_media_packet_header_t media_header;
475     if (!read_media_data_header(packet, size, &pos, &media_header)) return;
476 
477     avdtp_sbc_codec_header_t sbc_header;
478     if (!read_sbc_header(packet, size, &pos, &sbc_header)) return;
479 
480 #ifdef STORE_TO_SBC_FILE
481     fwrite(packet+pos, size-pos, 1, sbc_file);
482 #endif
483 
484     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
485     // process data right away if there's no audio implementation active, e.g. on posix systems to store as .wav
486     if (!audio){
487         btstack_sbc_decoder_process_data(&state, 0, packet+pos, size-pos);
488         return;
489     }
490 
491     // store sbc frame size for buffer management
492     sbc_frame_size = (size-pos)/ sbc_header.num_frames;
493 
494     int status = btstack_ring_buffer_write(&sbc_frame_ring_buffer, packet+pos, size-pos);
495     if (status){
496         printf("Error storing samples in SBC ring buffer!!!\n");
497     }
498 
499     // decide on audio sync drift based on number of sbc frames in queue
500     int sbc_frames_in_buffer = btstack_ring_buffer_bytes_available(&sbc_frame_ring_buffer) / sbc_frame_size;
501     uint32_t resampling_factor;
502 
503     // nomimal factor (fixed-point 2^16) and compensation offset
504     uint32_t nomimal_factor = 0x10000;
505     uint32_t compensation   = 0x00100;
506 
507     if (sbc_frames_in_buffer < OPTIMAL_FRAMES_MIN){
508     	resampling_factor = nomimal_factor - compensation;    // stretch samples
509     } else if (sbc_frames_in_buffer <= OPTIMAL_FRAMES_MAX){
510     	resampling_factor = nomimal_factor;                   // nothing to do
511     } else {
512     	resampling_factor = nomimal_factor + compensation;    // compress samples
513     }
514 
515     btstack_resample_set_factor(&resample_instance, resampling_factor);
516 
517     // start stream if enough frames buffered
518     if (!audio_stream_started && sbc_frames_in_buffer >= OPTIMAL_FRAMES_MIN){
519         audio_stream_started = 1;
520         // setup audio playback
521         if (audio){
522             audio->start_stream();
523         }
524     }
525 }
526 
527 static int read_sbc_header(uint8_t * packet, int size, int * offset, avdtp_sbc_codec_header_t * sbc_header){
528     int sbc_header_len = 12; // without crc
529     int pos = *offset;
530 
531     if (size - pos < sbc_header_len){
532         printf("Not enough data to read SBC header, expected %d, received %d\n", sbc_header_len, size-pos);
533         return 0;
534     }
535 
536     sbc_header->fragmentation = get_bit16(packet[pos], 7);
537     sbc_header->starting_packet = get_bit16(packet[pos], 6);
538     sbc_header->last_packet = get_bit16(packet[pos], 5);
539     sbc_header->num_frames = packet[pos] & 0x0f;
540     pos++;
541     *offset = pos;
542     return 1;
543 }
544 
545 static int read_media_data_header(uint8_t *packet, int size, int *offset, avdtp_media_packet_header_t *media_header){
546     int media_header_len = 12; // without crc
547     int pos = *offset;
548 
549     if (size - pos < media_header_len){
550         printf("Not enough data to read media packet header, expected %d, received %d\n", media_header_len, size-pos);
551         return 0;
552     }
553 
554     media_header->version = packet[pos] & 0x03;
555     media_header->padding = get_bit16(packet[pos],2);
556     media_header->extension = get_bit16(packet[pos],3);
557     media_header->csrc_count = (packet[pos] >> 4) & 0x0F;
558     pos++;
559 
560     media_header->marker = get_bit16(packet[pos],0);
561     media_header->payload_type  = (packet[pos] >> 1) & 0x7F;
562     pos++;
563 
564     media_header->sequence_number = big_endian_read_16(packet, pos);
565     pos+=2;
566 
567     media_header->timestamp = big_endian_read_32(packet, pos);
568     pos+=4;
569 
570     media_header->synchronization_source = big_endian_read_32(packet, pos);
571     pos+=4;
572     *offset = pos;
573     return 1;
574 }
575 
576 static void dump_sbc_configuration(avdtp_media_codec_configuration_sbc_t configuration){
577     printf("    - num_channels: %d\n", configuration.num_channels);
578     printf("    - sampling_frequency: %d\n", configuration.sampling_frequency);
579     printf("    - channel_mode: %d\n", configuration.channel_mode);
580     printf("    - block_length: %d\n", configuration.block_length);
581     printf("    - subbands: %d\n", configuration.subbands);
582     printf("    - allocation_method: %d\n", configuration.allocation_method);
583     printf("    - bitpool_value [%d, %d] \n", configuration.min_bitpool_value, configuration.max_bitpool_value);
584     printf("\n");
585 }
586 
587 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
588     UNUSED(channel);
589     UNUSED(size);
590     uint16_t local_cid;
591     uint8_t  status = 0xFF;
592     bd_addr_t adress;
593 
594     if (packet_type != HCI_EVENT_PACKET) return;
595     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
596     switch (packet[2]){
597         case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED: {
598             local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
599             status = avrcp_subevent_connection_established_get_status(packet);
600             if (status != ERROR_CODE_SUCCESS){
601                 printf("AVRCP: Connection failed: status 0x%02x\n", status);
602                 avrcp_cid = 0;
603                 return;
604             }
605 
606             avrcp_cid = local_cid;
607             avrcp_connected = 1;
608             avrcp_subevent_connection_established_get_bd_addr(packet, adress);
609             printf("AVRCP: Connected to %s, cid 0x%02x\n", bd_addr_to_str(adress), avrcp_cid);
610 
611             // automatically enable notifications
612             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED);
613             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED);
614             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
615             return;
616         }
617 
618         case AVRCP_SUBEVENT_CONNECTION_RELEASED:
619             printf("AVRCP: Channel released: cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
620             avrcp_cid = 0;
621             avrcp_connected = 0;
622             return;
623         default:
624             break;
625     }
626 }
627 
628 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
629     UNUSED(channel);
630     UNUSED(size);
631     uint8_t  status = 0xFF;
632 
633     if (packet_type != HCI_EVENT_PACKET) return;
634     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
635 
636     status = packet[5];
637     if (!avrcp_cid) return;
638 
639     // ignore INTERIM status
640     if (status == AVRCP_CTYPE_RESPONSE_INTERIM){
641         switch (packet[2]){
642             case AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_POS_CHANGED:{
643                 uint32_t playback_position_ms = avrcp_subevent_notification_playback_pos_changed_get_playback_position_ms(packet);
644                 if (playback_position_ms == AVRCP_NO_TRACK_SELECTED_PLAYBACK_POSITION_CHANGED){
645                     printf("AVRCP Controller: playback position changed, no track is selected\n");
646                 }
647                 break;
648             }
649             default:
650                 break;
651         }
652         return;
653     }
654 
655     memset(avrcp_subevent_value, 0, sizeof(avrcp_subevent_value));
656     switch (packet[2]){
657         case AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_POS_CHANGED:
658             printf("AVRCP Controller: Playback position changed, position %d ms\n", (unsigned int) avrcp_subevent_notification_playback_pos_changed_get_playback_position_ms(packet));
659             break;
660         case AVRCP_SUBEVENT_NOTIFICATION_PLAYBACK_STATUS_CHANGED:
661             printf("AVRCP Controller: Playback status changed %s\n", avrcp_play_status2str(avrcp_subevent_notification_playback_status_changed_get_play_status(packet)));
662             return;
663         case AVRCP_SUBEVENT_NOTIFICATION_NOW_PLAYING_CONTENT_CHANGED:
664             printf("AVRCP Controller: Playing content changed\n");
665             return;
666         case AVRCP_SUBEVENT_NOTIFICATION_TRACK_CHANGED:
667             printf("AVRCP Controller: Track changed\n");
668             return;
669         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
670             printf("AVRCP Controller: Absolute volume changed %d\n", avrcp_subevent_notification_volume_changed_get_absolute_volume(packet));
671             return;
672         case AVRCP_SUBEVENT_NOTIFICATION_AVAILABLE_PLAYERS_CHANGED:
673             printf("AVRCP Controller: Changed\n");
674             return;
675         case AVRCP_SUBEVENT_SHUFFLE_AND_REPEAT_MODE:{
676             uint8_t shuffle_mode = avrcp_subevent_shuffle_and_repeat_mode_get_shuffle_mode(packet);
677             uint8_t repeat_mode  = avrcp_subevent_shuffle_and_repeat_mode_get_repeat_mode(packet);
678             printf("AVRCP Controller: %s, %s\n", avrcp_shuffle2str(shuffle_mode), avrcp_repeat2str(repeat_mode));
679             break;
680         }
681         case AVRCP_SUBEVENT_NOW_PLAYING_TRACK_INFO:
682             printf("AVRCP Controller:     Track: %d\n", avrcp_subevent_now_playing_track_info_get_track(packet));
683             break;
684 
685         case AVRCP_SUBEVENT_NOW_PLAYING_TOTAL_TRACKS_INFO:
686             printf("AVRCP Controller:     Total Tracks: %d\n", avrcp_subevent_now_playing_total_tracks_info_get_total_tracks(packet));
687             break;
688 
689         case AVRCP_SUBEVENT_NOW_PLAYING_TITLE_INFO:
690             if (avrcp_subevent_now_playing_title_info_get_value_len(packet) > 0){
691                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_title_info_get_value(packet), avrcp_subevent_now_playing_title_info_get_value_len(packet));
692                 printf("AVRCP Controller:     Title: %s\n", avrcp_subevent_value);
693             }
694             break;
695 
696         case AVRCP_SUBEVENT_NOW_PLAYING_ARTIST_INFO:
697             if (avrcp_subevent_now_playing_artist_info_get_value_len(packet) > 0){
698                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_artist_info_get_value(packet), avrcp_subevent_now_playing_artist_info_get_value_len(packet));
699                 printf("AVRCP Controller:     Artist: %s\n", avrcp_subevent_value);
700             }
701             break;
702 
703         case AVRCP_SUBEVENT_NOW_PLAYING_ALBUM_INFO:
704             if (avrcp_subevent_now_playing_album_info_get_value_len(packet) > 0){
705                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_album_info_get_value(packet), avrcp_subevent_now_playing_album_info_get_value_len(packet));
706                 printf("AVRCP Controller:     Album: %s\n", avrcp_subevent_value);
707             }
708             break;
709 
710         case AVRCP_SUBEVENT_NOW_PLAYING_GENRE_INFO:
711             if (avrcp_subevent_now_playing_genre_info_get_value_len(packet) > 0){
712                 memcpy(avrcp_subevent_value, avrcp_subevent_now_playing_genre_info_get_value(packet), avrcp_subevent_now_playing_genre_info_get_value_len(packet));
713                 printf("AVRCP Controller:     Genre: %s\n", avrcp_subevent_value);
714             }
715             break;
716 
717         case AVRCP_SUBEVENT_PLAY_STATUS:
718             printf("AVRCP Controller: Song length %"PRIu32" ms, Song position %"PRIu32" ms, Play status %s\n",
719                 avrcp_subevent_play_status_get_song_length(packet),
720                 avrcp_subevent_play_status_get_song_position(packet),
721                 avrcp_play_status2str(avrcp_subevent_play_status_get_play_status(packet)));
722             break;
723 
724         case AVRCP_SUBEVENT_OPERATION_COMPLETE:
725             printf("AVRCP Controller: %s complete\n", avrcp_operation2str(avrcp_subevent_operation_complete_get_operation_id(packet)));
726             break;
727 
728         case AVRCP_SUBEVENT_OPERATION_START:
729             printf("AVRCP Controller: %s start\n", avrcp_operation2str(avrcp_subevent_operation_start_get_operation_id(packet)));
730             break;
731 
732         case AVRCP_SUBEVENT_NOTIFICATION_EVENT_TRACK_REACHED_END:
733             printf("AVRCP Controller: Track reached end\n");
734             break;
735 
736         case AVRCP_SUBEVENT_PLAYER_APPLICATION_VALUE_RESPONSE:
737             printf("A2DP  Sink      : Set Player App Value %s\n", avrcp_ctype2str(avrcp_subevent_player_application_value_response_get_command_type(packet)));
738             break;
739 
740 
741         default:
742             printf("AVRCP Controller: Event 0x%02x is not parsed\n", packet[2]);
743             break;
744     }
745 }
746 
747 static void avrcp_volume_changed(uint8_t volume){
748     const btstack_audio_sink_t * audio = btstack_audio_sink_get_instance();
749     if (audio){
750         audio->set_volume(volume);
751     }
752 }
753 
754 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
755     UNUSED(channel);
756     UNUSED(size);
757 
758     if (packet_type != HCI_EVENT_PACKET) return;
759     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
760 
761     uint8_t volume;
762 
763     switch (packet[2]){
764         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
765             volume = avrcp_subevent_notification_volume_changed_get_absolute_volume(packet);
766             volume_percentage = volume * 100 / 127;
767             printf("AVRCP Target    : Volume set to %d%% (%d)\n", volume_percentage, volume);
768             avrcp_volume_changed(volume);
769             break;
770 
771         case AVRCP_SUBEVENT_EVENT_IDS_QUERY:
772 #ifdef SUPPORT_VOLUME_CHANGE_NOTIFICATION
773             avrcp_target_supported_events(avrcp_cid, events_num, events, sizeof(events));
774 #else
775             avrcp_target_supported_events(avrcp_cid, 0, NULL, 0);
776 #endif
777             break;
778         case AVRCP_SUBEVENT_COMPANY_IDS_QUERY:
779             avrcp_target_supported_companies(avrcp_cid, companies_num, companies, sizeof(companies));
780             break;
781         case AVRCP_SUBEVENT_OPERATION:{
782             avrcp_operation_id_t operation_id = avrcp_subevent_operation_get_operation_id(packet);
783             switch (operation_id){
784                 case AVRCP_OPERATION_ID_PLAY:
785                     printf("AVRCP Target    : PLAY\n");
786                     break;
787                 case AVRCP_OPERATION_ID_PAUSE:
788                     printf("AVRCP Target    : PAUSE\n");
789                     break;
790                 case AVRCP_OPERATION_ID_STOP:
791                     printf("AVRCP Target    : STOP\n");
792                     break;
793                 case AVRCP_OPERATION_ID_REWIND:
794                     printf("AVRCP Target    : REWIND\n");
795                     break;
796                 case AVRCP_OPERATION_ID_FAST_FORWARD:
797                     printf("AVRCP Target    : FAST_FORWARD\n");
798                     break;
799                 case AVRCP_OPERATION_ID_FORWARD:
800                     printf("AVRCP Target    : FORWARD\n");
801                     break;
802                 case AVRCP_OPERATION_ID_BACKWARD:
803                     printf("AVRCP Target    : BACKWARD\n");
804                     break;
805                 case AVRCP_OPERATION_ID_SKIP:
806                     printf("AVRCP Target    : SKIP\n");
807                     break;
808                 case AVRCP_OPERATION_ID_MUTE:
809                     printf("AVRCP Target    : MUTE\n");
810                     break;
811                 case AVRCP_OPERATION_ID_CHANNEL_UP:
812                     printf("AVRCP Target    : CHANNEL_UP\n");
813                     break;
814                 case AVRCP_OPERATION_ID_CHANNEL_DOWN:
815                     printf("AVRCP Target    : CHANNEL_DOWN\n");
816                     break;
817                 case AVRCP_OPERATION_ID_SELECT:
818                     printf("AVRCP Target    : SELECT\n");
819                     break;
820                 case AVRCP_OPERATION_ID_UP:
821                     printf("AVRCP Target    : UP\n");
822                     break;
823                 case AVRCP_OPERATION_ID_DOWN:
824                     printf("AVRCP Target    : DOWN\n");
825                     break;
826                 case AVRCP_OPERATION_ID_LEFT:
827                     printf("AVRCP Target    : LEFT\n");
828                     break;
829                 case AVRCP_OPERATION_ID_RIGHT:
830                     printf("AVRCP Target    : RIGTH\n");
831                     break;
832                 case AVRCP_OPERATION_ID_ROOT_MENU:
833                     printf("AVRCP Target    : ROOT_MENU\n");
834                     break;
835                 default:
836                     return;
837             }
838             break;
839         }
840         default:
841             printf("AVRCP Target    : Event 0x%02x is not parsed\n", packet[2]);
842             break;
843     }
844 }
845 
846 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
847     UNUSED(channel);
848     UNUSED(size);
849     if (packet_type != HCI_EVENT_PACKET) return;
850     if (hci_event_packet_get_type(packet) == HCI_EVENT_PIN_CODE_REQUEST) {
851         bd_addr_t address;
852         printf("Pin code request - using '0000'\n");
853         hci_event_pin_code_request_get_bd_addr(packet, address);
854         gap_pin_code_response(address, "0000");
855     }
856 }
857 
858 static void a2dp_sink_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
859     UNUSED(channel);
860     UNUSED(size);
861     bd_addr_t address;
862     uint8_t status;
863 
864     if (packet_type != HCI_EVENT_PACKET) return;
865     if (hci_event_packet_get_type(packet) != HCI_EVENT_A2DP_META) return;
866 
867     switch (packet[2]){
868         case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_OTHER_CONFIGURATION:
869             printf("A2DP  Sink      : Received non SBC codec - not implemented\n");
870             break;
871         case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
872             printf("A2DP  Sink      : Received SBC codec configuration\n");
873             sbc_configuration.reconfigure = a2dp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
874             sbc_configuration.num_channels = a2dp_subevent_signaling_media_codec_sbc_configuration_get_num_channels(packet);
875             sbc_configuration.sampling_frequency = a2dp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
876             sbc_configuration.channel_mode = a2dp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
877             sbc_configuration.block_length = a2dp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
878             sbc_configuration.subbands = a2dp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
879             sbc_configuration.allocation_method = a2dp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
880             sbc_configuration.min_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
881             sbc_configuration.max_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
882             sbc_configuration.frames_per_buffer = sbc_configuration.subbands * sbc_configuration.block_length;
883             dump_sbc_configuration(sbc_configuration);
884 
885             if (sbc_configuration.reconfigure){
886                 media_processing_close();
887             }
888             // prepare media processing
889             media_processing_init(sbc_configuration);
890             break;
891         }
892         case A2DP_SUBEVENT_STREAM_ESTABLISHED:
893             a2dp_subevent_stream_established_get_bd_addr(packet, address);
894             status = a2dp_subevent_stream_established_get_status(packet);
895 
896             if (status){
897                 printf("A2DP  Sink      : Streaming connection failed, status 0x%02x\n", status);
898                 break;
899             }
900 
901             a2dp_cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
902             memcpy(device_addr, address, 6);
903             printf("A2DP  Sink      : Streaming connection is established, address %s, cid 0x%02X, local seid %d\n", bd_addr_to_str(address), a2dp_cid, a2dp_local_seid);
904             break;
905 
906         case A2DP_SUBEVENT_STREAM_STARTED:
907             printf("A2DP  Sink      : Stream started\n");
908             media_processing_start();
909             break;
910 
911         case A2DP_SUBEVENT_STREAM_SUSPENDED:
912             printf("A2DP  Sink      : Stream paused\n");
913             media_processing_pause();
914             break;
915 
916         case A2DP_SUBEVENT_STREAM_RELEASED:
917             printf("A2DP  Sink      : Stream released\n");
918             media_processing_close();
919             break;
920 
921         case A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
922             printf("A2DP  Sink      : Signaling connection released\n");
923             media_processing_close();
924             break;
925 
926         default:
927             printf("A2DP  Sink      : Not parsed 0x%02x\n", packet[2]);
928             break;
929     }
930 }
931 
932 #ifdef HAVE_BTSTACK_STDIN
933 static void show_usage(void){
934     bd_addr_t      iut_address;
935     gap_local_bd_addr(iut_address);
936     printf("\n--- Bluetooth AVDTP Sink/AVRCP Connection Test Console %s ---\n", bd_addr_to_str(iut_address));
937     printf("b      - AVDTP Sink create  connection to addr %s\n", bd_addr_to_str(device_addr));
938     printf("B      - AVDTP Sink disconnect\n");
939     printf("c      - AVRCP create connection to addr %s\n", bd_addr_to_str(device_addr));
940     printf("C      - AVRCP disconnect\n");
941 
942     printf("w - delay report\n");
943 
944     printf("\n--- Bluetooth AVRCP Commands %s ---\n", bd_addr_to_str(iut_address));
945     printf("O - get play status\n");
946     printf("j - get now playing info\n");
947     printf("k - play\n");
948     printf("K - stop\n");
949     printf("L - pause\n");
950     printf("u - start fast forward\n");
951     printf("U - stop  fast forward\n");
952     printf("n - start rewind\n");
953     printf("N - stop rewind\n");
954     printf("i - forward\n");
955     printf("I - backward\n");
956     printf("M - mute\n");
957     printf("r - skip\n");
958     printf("q - query repeat and shuffle mode\n");
959     printf("v - repeat single track\n");
960     printf("x - repeat all tracks\n");
961     printf("X - disable repeat mode\n");
962     printf("z - shuffle all tracks\n");
963     printf("Z - disable shuffle mode\n");
964 
965     printf("a/A - register/deregister TRACK_CHANGED\n");
966     printf("R/P - register/deregister PLAYBACK_POS_CHANGED\n");
967 
968     printf("\n--- Volume Control ---\n");
969     printf("t - volume up   for 10 percent\n");
970     printf("T - volume down for 10 percent\n");
971 
972     printf("---\n");
973 }
974 #endif
975 
976 #ifdef HAVE_BTSTACK_STDIN
977 static void stdin_process(char cmd){
978     uint8_t status = ERROR_CODE_SUCCESS;
979     uint8_t volume;
980 
981     switch (cmd){
982         case 'b':
983             status = a2dp_sink_establish_stream(device_addr, a2dp_local_seid, &a2dp_cid);
984             printf(" - Create AVDTP connection to addr %s, and local seid %d, expected cid 0x%02x.\n", bd_addr_to_str(device_addr), a2dp_local_seid, a2dp_cid);
985             break;
986         case 'B':
987             printf(" - AVDTP disconnect from addr %s.\n", bd_addr_to_str(device_addr));
988             a2dp_sink_disconnect(a2dp_cid);
989             break;
990         case 'c':
991             printf(" - Create AVRCP connection to addr %s.\n", bd_addr_to_str(device_addr));
992             status = avrcp_connect(device_addr, &avrcp_cid);
993             break;
994         case 'C':
995             printf(" - AVRCP disconnect from addr %s.\n", bd_addr_to_str(device_addr));
996             status = avrcp_disconnect(avrcp_cid);
997             break;
998 
999         case '\n':
1000         case '\r':
1001             break;
1002         case 'w':
1003             printf("Send delay report\n");
1004             avdtp_sink_delay_report(a2dp_cid, a2dp_local_seid, 100);
1005             break;
1006         // Volume Control
1007         case 't':
1008             volume_percentage = volume_percentage <= 90 ? volume_percentage + 10 : 100;
1009             volume = volume_percentage * 127 / 100;
1010             printf(" - volume up   for 10 percent, %d%% (%d) \n", volume_percentage, volume);
1011             status = avrcp_target_volume_changed(avrcp_cid, volume);
1012             avrcp_volume_changed(volume);
1013             break;
1014         case 'T':
1015             volume_percentage = volume_percentage >= 10 ? volume_percentage - 10 : 0;
1016             volume = volume_percentage * 127 / 100;
1017             printf(" - volume down for 10 percent, %d%% (%d) \n", volume_percentage, volume);
1018             status = avrcp_target_volume_changed(avrcp_cid, volume);
1019             avrcp_volume_changed(volume);
1020             break;
1021 
1022         case 'O':
1023             printf(" - get play status\n");
1024             status = avrcp_controller_get_play_status(avrcp_cid);
1025             break;
1026         case 'j':
1027             printf(" - get now playing info\n");
1028             status = avrcp_controller_get_now_playing_info(avrcp_cid);
1029             break;
1030         case 'k':
1031             printf(" - play\n");
1032             status = avrcp_controller_play(avrcp_cid);
1033             break;
1034         case 'K':
1035             printf(" - stop\n");
1036             status = avrcp_controller_stop(avrcp_cid);
1037             break;
1038         case 'L':
1039             printf(" - pause\n");
1040             status = avrcp_controller_pause(avrcp_cid);
1041             break;
1042         case 'u':
1043             printf(" - start fast forward\n");
1044             status = avrcp_controller_press_and_hold_fast_forward(avrcp_cid);
1045             break;
1046         case 'U':
1047             printf(" - stop fast forward\n");
1048             status = avrcp_controller_release_press_and_hold_cmd(avrcp_cid);
1049             break;
1050         case 'n':
1051             printf(" - start rewind\n");
1052             status = avrcp_controller_press_and_hold_rewind(avrcp_cid);
1053             break;
1054         case 'N':
1055             printf(" - stop rewind\n");
1056             status = avrcp_controller_release_press_and_hold_cmd(avrcp_cid);
1057             break;
1058         case 'i':
1059             printf(" - forward\n");
1060             status = avrcp_controller_forward(avrcp_cid);
1061             break;
1062         case 'I':
1063             printf(" - backward\n");
1064             status = avrcp_controller_backward(avrcp_cid);
1065             break;
1066         case 'M':
1067             printf(" - mute\n");
1068             status = avrcp_controller_mute(avrcp_cid);
1069             break;
1070         case 'r':
1071             printf(" - skip\n");
1072             status = avrcp_controller_skip(avrcp_cid);
1073             break;
1074         case 'q':
1075             printf(" - query repeat and shuffle mode\n");
1076             status = avrcp_controller_query_shuffle_and_repeat_modes(avrcp_cid);
1077             break;
1078         case 'v':
1079             printf(" - repeat single track\n");
1080             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_SINGLE_TRACK);
1081             break;
1082         case 'x':
1083             printf(" - repeat all tracks\n");
1084             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_ALL_TRACKS);
1085             break;
1086         case 'X':
1087             printf(" - disable repeat mode\n");
1088             status = avrcp_controller_set_repeat_mode(avrcp_cid, AVRCP_REPEAT_MODE_OFF);
1089             break;
1090         case 'z':
1091             printf(" - shuffle all tracks\n");
1092             status = avrcp_controller_set_shuffle_mode(avrcp_cid, AVRCP_SHUFFLE_MODE_ALL_TRACKS);
1093             break;
1094         case 'Z':
1095             printf(" - disable shuffle mode\n");
1096             status = avrcp_controller_set_shuffle_mode(avrcp_cid, AVRCP_SHUFFLE_MODE_OFF);
1097             break;
1098         case 'a':
1099             printf("AVRCP: enable notification TRACK_CHANGED\n");
1100             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
1101             break;
1102         case 'A':
1103             printf("AVRCP: disable notification TRACK_CHANGED\n");
1104             avrcp_controller_disable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
1105             break;
1106         case 'R':
1107             printf("AVRCP: enable notification PLAYBACK_POS_CHANGED\n");
1108             avrcp_controller_enable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_POS_CHANGED);
1109             break;
1110         case 'P':
1111             printf("AVRCP: disable notification PLAYBACK_POS_CHANGED\n");
1112             avrcp_controller_disable_notification(avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_POS_CHANGED);
1113             break;
1114 
1115         default:
1116             show_usage();
1117             return;
1118     }
1119     if (status != ERROR_CODE_SUCCESS){
1120         printf("Could not perform command, status 0x%02x\n", status);
1121     }
1122 }
1123 #endif
1124 
1125 int btstack_main(int argc, const char * argv[]);
1126 int btstack_main(int argc, const char * argv[]){
1127     UNUSED(argc);
1128     (void)argv;
1129 
1130     a2dp_and_avrcp_setup();
1131 
1132 #ifdef HAVE_BTSTACK_STDIN
1133     // parse human readable Bluetooth address
1134     sscanf_bd_addr(device_addr_string, device_addr);
1135     btstack_stdin_setup(stdin_process);
1136 #endif
1137 
1138     // turn on!
1139     printf("Starting BTstack ...\n");
1140     hci_power_control(HCI_POWER_ON);
1141     return 0;
1142 }
1143 /* EXAMPLE_END */