xref: /btstack/example/a2dp_source_demo.c (revision bce3db218b0bb32211ad4de9ff6b81d412f5d3d0)
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_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 <stdlib.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     uint16_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 typedef struct {
151     int reconfigure;
152 
153     int num_channels;
154     int sampling_frequency;
155     int block_length;
156     int subbands;
157     int min_bitpool_value;
158     int max_bitpool_value;
159     btstack_sbc_channel_mode_t      channel_mode;
160     btstack_sbc_allocation_method_t allocation_method;
161 } media_codec_configuration_sbc_t;
162 
163 static btstack_packet_callback_registration_t hci_event_callback_registration;
164 
165 // pts:             static const char * device_addr_string = "00:1B:DC:08:0A:A5";
166 // pts:             static const char * device_addr_string = "00:1B:DC:08:E2:72";
167 // mac 2013:        static const char * device_addr_string = "84:38:35:65:d1:15";
168 // phone 2013:      static const char * device_addr_string = "D8:BB:2C:DF:F0:F2";
169 // Minijambox:
170 static const char * device_addr_string = "00:21:3C:AC:F7:38";
171 // Philips SHB9100: static const char * device_addr_string = "00:22:37:05:FD:E8";
172 // RT-B6:           static const char * device_addr_string = "00:75:58:FF:C9:7D";
173 // BT dongle:       static const char * device_addr_string = "00:1A:7D:DA:71:0A";
174 // Sony MDR-ZX330BT static const char * device_addr_string = "00:18:09:28:50:18";
175 // Panda (BM6)      static const char * device_addr_string = "4F:3F:66:52:8B:E0";
176 // BeatsX:          static const char * device_addr_string = "DC:D3:A2:89:57:FB";
177 // Green mushroom:  static const char * device_addr_string = "41:42:2A:ED:D6:F3";
178 
179 static bd_addr_t device_addr;
180 
181 static uint8_t sdp_a2dp_source_service_buffer[150];
182 static uint8_t sdp_avrcp_target_service_buffer[200];
183 static uint8_t sdp_avrcp_controller_service_buffer[200];
184 static uint8_t device_id_sdp_service_buffer[100];
185 
186 static media_codec_configuration_sbc_t sbc_configuration;
187 static btstack_sbc_encoder_state_t sbc_encoder_state;
188 
189 static uint8_t media_sbc_codec_configuration[4];
190 static a2dp_media_sending_context_t media_tracker;
191 
192 static stream_data_source_t data_source;
193 
194 static int sine_phase;
195 static int current_sample_rate = 44100;
196 static int new_sample_rate = 44100;
197 
198 static int hxcmod_initialized;
199 static modcontext mod_context;
200 static tracker_buffer_state trkbuf;
201 
202 /* AVRCP Target context START */
203 static uint8_t  companies_num = 1;
204 static uint8_t  companies[] = {
205     0x00, 0x19, 0x58 //BT SIG registered CompanyID
206 };
207 
208 static uint8_t events_num = 6;
209 static uint8_t events[] = {
210     AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED,
211     AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED,
212     AVRCP_NOTIFICATION_EVENT_PLAYER_APPLICATION_SETTING_CHANGED,
213     AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED,
214     AVRCP_NOTIFICATION_EVENT_AVAILABLE_PLAYERS_CHANGED,
215     AVRCP_NOTIFICATION_EVENT_ADDRESSED_PLAYER_CHANGED
216 };
217 
218 typedef struct {
219     uint8_t track_id[8];
220     uint32_t song_length_ms;
221     avrcp_playback_status_t status;
222     uint32_t song_position_ms; // 0xFFFFFFFF if not supported
223 } avrcp_play_status_info_t;
224 
225 // python -c "print('a'*512)"
226 static const char title[] = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
227 
228 avrcp_track_t tracks[] = {
229     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, 1, "Sine", "Generated", "A2DP Source Demo", "monotone", 12345},
230     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}, 2, "Nao-deceased", "Decease", "A2DP Source Demo", "vivid", 12345},
231     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03}, 3, (char *)title, "Decease", "A2DP Source Demo", "vivid", 12345},
232 };
233 int current_track_index;
234 avrcp_play_status_info_t play_info;
235 
236 /* AVRCP Target context END */
237 
238 /* @section Main Application Setup
239  *
240  * @text The Listing MainConfiguration shows how to setup AD2P Source and AVRCP services.
241  * Besides calling init() method for each service, you'll also need to register several packet handlers:
242  * - hci_packet_handler - handles legacy pairing, here by using fixed '0000' pin code.
243  * - 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).
244  * - avrcp_packet_handler - receives connect/disconnect event.
245  * - avrcp_controller_packet_handler - receives answers for sent AVRCP commands.
246  * - avrcp_target_packet_handler - receives AVRCP commands, and registered notifications.
247  * - 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.
248  *
249  * @text To announce A2DP Source and AVRCP services, you need to create corresponding
250  * SDP records and register them with the SDP service.
251  */
252 
253 /* LISTING_START(MainConfiguration): Setup Audio Source and AVRCP Target services */
254 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
255 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t event_size);
256 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
257 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
258 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
259 #ifdef HAVE_BTSTACK_STDIN
260 static void stdin_process(char cmd);
261 #endif
262 
263 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate);
264 
265 static int a2dp_source_and_avrcp_services_init(void){
266     // Request role change on reconnecting headset to always use them in slave mode
267     hci_set_master_slave_policy(0);
268 
269     l2cap_init();
270     // Initialize  A2DP Source
271     a2dp_source_init();
272     a2dp_source_register_packet_handler(&a2dp_source_packet_handler);
273 
274     // Create stream endpoint
275     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));
276     if (!local_stream_endpoint){
277         printf("A2DP Source: not enough memory to create local stream endpoint\n");
278         return 1;
279     }
280 
281     // Store stream enpoint's SEP ID, as it is used by A2DP API to indentify the stream endpoint
282     media_tracker.local_seid = avdtp_local_seid(local_stream_endpoint);
283     avdtp_source_register_delay_reporting_category(media_tracker.local_seid);
284 
285     // Initialize AVRCP Service
286     avrcp_init();
287     avrcp_register_packet_handler(&avrcp_packet_handler);
288     // Initialize AVRCP Target
289     avrcp_target_init();
290     avrcp_target_register_packet_handler(&avrcp_target_packet_handler);
291     // Initialize AVRCP Controller
292     avrcp_controller_init();
293     avrcp_controller_register_packet_handler(&avrcp_controller_packet_handler);
294 
295     // Initialize SDP,
296     sdp_init();
297 
298     // Create A2DP Source service record and register it with SDP
299     memset(sdp_a2dp_source_service_buffer, 0, sizeof(sdp_a2dp_source_service_buffer));
300     a2dp_source_create_sdp_record(sdp_a2dp_source_service_buffer, 0x10001, AVDTP_SOURCE_FEATURE_MASK_PLAYER, NULL, NULL);
301     sdp_register_service(sdp_a2dp_source_service_buffer);
302 
303     // Create AVRCP Target service record and register it with SDP. We receive Category 1 commands from the headphone, e.g. play/pause
304     memset(sdp_avrcp_target_service_buffer, 0, sizeof(sdp_avrcp_target_service_buffer));
305     uint16_t supported_features = AVRCP_FEATURE_MASK_CATEGORY_PLAYER_OR_RECORDER;
306 #ifdef AVRCP_BROWSING_ENABLED
307     supported_features |= AVRCP_FEATURE_MASK_BROWSING;
308 #endif
309     avrcp_target_create_sdp_record(sdp_avrcp_target_service_buffer, 0x10002, supported_features, NULL, NULL);
310     sdp_register_service(sdp_avrcp_target_service_buffer);
311 
312     // Create AVRCP Controller service record and register it with SDP. We send Category 2 commands to the headphone, e.g. volume up/down
313     memset(sdp_avrcp_controller_service_buffer, 0, sizeof(sdp_avrcp_controller_service_buffer));
314     uint16_t controller_supported_features = AVRCP_FEATURE_MASK_CATEGORY_MONITOR_OR_AMPLIFIER;
315     avrcp_controller_create_sdp_record(sdp_avrcp_controller_service_buffer, 0x10003, controller_supported_features, NULL, NULL);
316     sdp_register_service(sdp_avrcp_controller_service_buffer);
317 
318     // Register Device ID (PnP) service SDP record
319     memset(device_id_sdp_service_buffer, 0, sizeof(device_id_sdp_service_buffer));
320     device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10004, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1);
321     sdp_register_service(device_id_sdp_service_buffer);
322 
323     // Set local name with a template Bluetooth address, that will be automatically
324     // replaced with a actual address once it is available, i.e. when BTstack boots
325     // up and starts talking to a Bluetooth module.
326     gap_set_local_name("A2DP Source 00:00:00:00:00:00");
327     gap_discoverable_control(1);
328     gap_set_class_of_device(0x200408);
329 
330     // Register for HCI events.
331     hci_event_callback_registration.callback = &hci_packet_handler;
332     hci_add_event_handler(&hci_event_callback_registration);
333 
334     a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
335 
336     // Parse human readable Bluetooth address.
337     sscanf_bd_addr(device_addr_string, device_addr);
338 
339 #ifdef HAVE_BTSTACK_STDIN
340     btstack_stdin_setup(stdin_process);
341 #endif
342     return 0;
343 }
344 /* LISTING_END */
345 
346 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate){
347     if (!hxcmod_initialized){
348         hxcmod_initialized = hxcmod_init(&mod_context);
349         if (!hxcmod_initialized) {
350             printf("could not initialize hxcmod\n");
351             return;
352         }
353     }
354     current_sample_rate = sample_rate;
355     media_tracker.sbc_storage_count = 0;
356     media_tracker.samples_ready = 0;
357     hxcmod_unload(&mod_context);
358     hxcmod_setcfg(&mod_context, current_sample_rate, 16, 1, 1, 1);
359     hxcmod_load(&mod_context, (void *) &mod_data, mod_len);
360 }
361 
362 static void a2dp_demo_send_media_packet(void){
363     int num_bytes_in_frame = btstack_sbc_encoder_sbc_buffer_length();
364     int bytes_in_storage = media_tracker.sbc_storage_count;
365     uint8_t num_frames = bytes_in_storage / num_bytes_in_frame;
366     // Prepend SBC Header
367     media_tracker.sbc_storage[0] = num_frames;  // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
368     avdtp_source_stream_send_media_payload_rtp(media_tracker.a2dp_cid, media_tracker.local_seid, 0, media_tracker.sbc_storage, bytes_in_storage + 1);
369 
370     media_tracker.sbc_storage_count = 0;
371     media_tracker.sbc_ready_to_send = 0;
372 }
373 
374 static void produce_sine_audio(int16_t * pcm_buffer, int num_samples_to_write){
375     int count;
376     for (count = 0; count < num_samples_to_write ; count++){
377         switch (current_sample_rate){
378             case 44100:
379                 pcm_buffer[count * 2]     = sine_int16_44100[sine_phase];
380                 pcm_buffer[count * 2 + 1] = sine_int16_44100[sine_phase];
381                 sine_phase++;
382                 if (sine_phase >= num_samples_sine_int16_44100){
383                     sine_phase -= num_samples_sine_int16_44100;
384                 }
385                 break;
386             case 48000:
387                 pcm_buffer[count * 2]     = sine_int16_48000[sine_phase];
388                 pcm_buffer[count * 2 + 1] = sine_int16_48000[sine_phase];
389                 sine_phase++;
390                 if (sine_phase >= num_samples_sine_int16_48000){
391                     sine_phase -= num_samples_sine_int16_48000;
392                 }
393                 break;
394             default:
395                 break;
396         }
397     }
398 }
399 
400 static void produce_mod_audio(int16_t * pcm_buffer, int num_samples_to_write){
401     hxcmod_fillbuffer(&mod_context, (unsigned short *) &pcm_buffer[0], num_samples_to_write, &trkbuf);
402 }
403 
404 static void produce_audio(int16_t * pcm_buffer, int num_samples){
405     switch (data_source){
406         case STREAM_SINE:
407             produce_sine_audio(pcm_buffer, num_samples);
408             break;
409         case STREAM_MOD:
410             produce_mod_audio(pcm_buffer, num_samples);
411             break;
412         default:
413             break;
414     }
415 #ifdef VOLUME_REDUCTION
416     int i;
417     for (i=0;i<num_samples*2;i++){
418         if (pcm_buffer[i] > 0){
419             pcm_buffer[i] =     pcm_buffer[i]  >> VOLUME_REDUCTION;
420         } else {
421             pcm_buffer[i] = -((-pcm_buffer[i]) >> VOLUME_REDUCTION);
422         }
423     }
424 #endif
425 }
426 
427 static int a2dp_demo_fill_sbc_audio_buffer(a2dp_media_sending_context_t * context){
428     // perform sbc encoding
429     int total_num_bytes_read = 0;
430     unsigned int num_audio_samples_per_sbc_buffer = btstack_sbc_encoder_num_audio_frames();
431     while (context->samples_ready >= num_audio_samples_per_sbc_buffer
432         && (context->max_media_payload_size - context->sbc_storage_count) >= btstack_sbc_encoder_sbc_buffer_length()){
433 
434         int16_t pcm_frame[256*NUM_CHANNELS];
435 
436         produce_audio(pcm_frame, num_audio_samples_per_sbc_buffer);
437         btstack_sbc_encoder_process_data(pcm_frame);
438 
439         uint16_t sbc_frame_size = btstack_sbc_encoder_sbc_buffer_length();
440         uint8_t * sbc_frame = btstack_sbc_encoder_sbc_buffer();
441 
442         total_num_bytes_read += num_audio_samples_per_sbc_buffer;
443         // first byte in sbc storage contains sbc media header
444         memcpy(&context->sbc_storage[1 + context->sbc_storage_count], sbc_frame, sbc_frame_size);
445         context->sbc_storage_count += sbc_frame_size;
446         context->samples_ready -= num_audio_samples_per_sbc_buffer;
447     }
448     return total_num_bytes_read;
449 }
450 
451 static void a2dp_demo_audio_timeout_handler(btstack_timer_source_t * timer){
452     a2dp_media_sending_context_t * context = (a2dp_media_sending_context_t *) btstack_run_loop_get_timer_context(timer);
453     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
454     btstack_run_loop_add_timer(&context->audio_timer);
455     uint32_t now = btstack_run_loop_get_time_ms();
456 
457     uint32_t update_period_ms = AUDIO_TIMEOUT_MS;
458     if (context->time_audio_data_sent > 0){
459         update_period_ms = now - context->time_audio_data_sent;
460     }
461 
462     uint32_t num_samples = (update_period_ms * current_sample_rate) / 1000;
463     context->acc_num_missed_samples += (update_period_ms * current_sample_rate) % 1000;
464 
465     while (context->acc_num_missed_samples >= 1000){
466         num_samples++;
467         context->acc_num_missed_samples -= 1000;
468     }
469     context->time_audio_data_sent = now;
470     context->samples_ready += num_samples;
471 
472     if (context->sbc_ready_to_send) return;
473 
474     a2dp_demo_fill_sbc_audio_buffer(context);
475 
476     if ((context->sbc_storage_count + btstack_sbc_encoder_sbc_buffer_length()) > context->max_media_payload_size){
477         // schedule sending
478         context->sbc_ready_to_send = 1;
479         a2dp_source_stream_endpoint_request_can_send_now(context->a2dp_cid, context->local_seid);
480     }
481 }
482 
483 static void a2dp_demo_timer_start(a2dp_media_sending_context_t * context){
484     context->max_media_payload_size = btstack_min(a2dp_max_media_payload_size(context->a2dp_cid, context->local_seid), SBC_STORAGE_SIZE);
485     context->sbc_storage_count = 0;
486     context->sbc_ready_to_send = 0;
487     context->streaming = 1;
488     btstack_run_loop_remove_timer(&context->audio_timer);
489     btstack_run_loop_set_timer_handler(&context->audio_timer, a2dp_demo_audio_timeout_handler);
490     btstack_run_loop_set_timer_context(&context->audio_timer, context);
491     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
492     btstack_run_loop_add_timer(&context->audio_timer);
493 }
494 
495 static void a2dp_demo_timer_stop(a2dp_media_sending_context_t * context){
496     context->time_audio_data_sent = 0;
497     context->acc_num_missed_samples = 0;
498     context->samples_ready = 0;
499     context->streaming = 1;
500     context->sbc_storage_count = 0;
501     context->sbc_ready_to_send = 0;
502     btstack_run_loop_remove_timer(&context->audio_timer);
503 }
504 
505 static void dump_sbc_configuration(media_codec_configuration_sbc_t * configuration){
506     printf("Received media codec configuration:\n");
507     printf("    - num_channels: %d\n", configuration->num_channels);
508     printf("    - sampling_frequency: %d\n", configuration->sampling_frequency);
509     printf("    - channel_mode: %d\n", configuration->channel_mode);
510     printf("    - block_length: %d\n", configuration->block_length);
511     printf("    - subbands: %d\n", configuration->subbands);
512     printf("    - allocation_method: %d\n", configuration->allocation_method);
513     printf("    - bitpool_value [%d, %d] \n", configuration->min_bitpool_value, configuration->max_bitpool_value);
514 }
515 
516 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
517     UNUSED(channel);
518     UNUSED(size);
519     if (packet_type != HCI_EVENT_PACKET) return;
520 
521 #ifndef HAVE_BTSTACK_STDIN
522     if (hci_event_packet_get_type(packet) == BTSTACK_EVENT_STATE){
523         if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) return;
524         printf("Create A2DP Source connection to addr %s.\n", bd_addr_to_str(device_addr));
525         uint8_t status = a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
526         if (status != ERROR_CODE_SUCCESS){
527             printf("Could not perform command, status 0x%2x\n", status);
528         }
529         return;
530     }
531 #endif
532 
533     if (hci_event_packet_get_type(packet) == HCI_EVENT_PIN_CODE_REQUEST) {
534         bd_addr_t address;
535         printf("Pin code request - using '0000'\n");
536         hci_event_pin_code_request_get_bd_addr(packet, address);
537         gap_pin_code_response(address, "0000");
538     }
539 }
540 
541 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
542     UNUSED(channel);
543     UNUSED(size);
544     uint8_t status;
545     uint8_t local_seid;
546     bd_addr_t address;
547     uint16_t cid;
548 
549     avdtp_channel_mode_t channel_mode;
550     uint8_t allocation_method;
551 
552     if (packet_type != HCI_EVENT_PACKET) return;
553     if (hci_event_packet_get_type(packet) != HCI_EVENT_A2DP_META) return;
554 
555     switch (hci_event_a2dp_meta_get_subevent_code(packet)){
556         case A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
557             a2dp_subevent_signaling_connection_established_get_bd_addr(packet, address);
558             cid = a2dp_subevent_signaling_connection_established_get_a2dp_cid(packet);
559             status = a2dp_subevent_signaling_connection_established_get_status(packet);
560 
561             if (status != ERROR_CODE_SUCCESS){
562                 printf("A2DP Source: Connection failed, status 0x%02x, cid 0x%02x, a2dp_cid 0x%02x \n", status, cid, media_tracker.a2dp_cid);
563                 media_tracker.a2dp_cid = 0;
564                 break;
565             }
566             media_tracker.a2dp_cid = cid;
567             media_tracker.volume = 32;
568 
569             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);
570             break;
571 
572          case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
573             cid  = avdtp_subevent_signaling_media_codec_sbc_configuration_get_avdtp_cid(packet);
574             if (cid != media_tracker.a2dp_cid) return;
575 
576             media_tracker.remote_seid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet);
577 
578             sbc_configuration.reconfigure = a2dp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
579             sbc_configuration.num_channels = a2dp_subevent_signaling_media_codec_sbc_configuration_get_num_channels(packet);
580             sbc_configuration.sampling_frequency = a2dp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
581             sbc_configuration.block_length = a2dp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
582             sbc_configuration.subbands = a2dp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
583             sbc_configuration.min_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
584             sbc_configuration.max_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
585 
586             channel_mode = (avdtp_channel_mode_t) a2dp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
587             allocation_method = a2dp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
588 
589             printf("A2DP Source: Received SBC codec configuration, sampling frequency %u, a2dp_cid 0x%02x, local seid 0x%02x, remote seid 0x%02x.\n",
590                 sbc_configuration.sampling_frequency, cid,
591                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_local_seid(packet),
592                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet));
593 
594             // Adapt Bluetooth spec definition to SBC Encoder expected input
595             sbc_configuration.allocation_method = (btstack_sbc_allocation_method_t)(allocation_method - 1);
596             switch (channel_mode){
597                 case AVDTP_CHANNEL_MODE_JOINT_STEREO:
598                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
599                     break;
600                 case AVDTP_CHANNEL_MODE_STEREO:
601                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_STEREO;
602                     break;
603                 case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
604                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
605                     break;
606                 case AVDTP_CHANNEL_MODE_MONO:
607                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_MONO;
608                     break;
609                 default:
610                     btstack_assert(false);
611                     break;
612             }
613             dump_sbc_configuration(&sbc_configuration);
614 
615             btstack_sbc_encoder_init(&sbc_encoder_state, SBC_MODE_STANDARD,
616                 sbc_configuration.block_length, sbc_configuration.subbands,
617                 sbc_configuration.allocation_method, sbc_configuration.sampling_frequency,
618                 sbc_configuration.max_bitpool_value,
619                 sbc_configuration.channel_mode);
620             break;
621         }
622 
623         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
624             printf("A2DP Source: remote supports delay report, remote seid %d\n",
625                 avdtp_subevent_signaling_delay_reporting_capability_get_remote_seid(packet));
626             break;
627         case A2DP_SUBEVENT_SIGNALING_CAPABILITIES_DONE:
628             printf("A2DP Source: All capabilities reported, remote seid %d\n",
629                 avdtp_subevent_signaling_capabilities_done_get_remote_seid(packet));
630             break;
631 
632         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORT:
633             printf("A2DP Source: Received delay report of %d.%0d ms, local seid %d\n",
634                 avdtp_subevent_signaling_delay_report_get_delay_100us(packet)/10, avdtp_subevent_signaling_delay_report_get_delay_100us(packet)%10,
635                 avdtp_subevent_signaling_delay_report_get_local_seid(packet));
636             break;
637 
638         case A2DP_SUBEVENT_STREAM_ESTABLISHED:
639             a2dp_subevent_stream_established_get_bd_addr(packet, address);
640             status = a2dp_subevent_stream_established_get_status(packet);
641             if (status != ERROR_CODE_SUCCESS){
642                 printf("A2DP Source: Stream failed, status 0x%02x.\n", status);
643                 break;
644             }
645 
646             local_seid = a2dp_subevent_stream_established_get_local_seid(packet);
647             cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
648 
649             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));
650 
651             a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
652             media_tracker.stream_opened = 1;
653             data_source = STREAM_MOD;
654             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
655             break;
656 
657         case A2DP_SUBEVENT_STREAM_RECONFIGURED:
658             status = a2dp_subevent_stream_reconfigured_get_status(packet);
659             local_seid = a2dp_subevent_stream_reconfigured_get_local_seid(packet);
660             cid = a2dp_subevent_stream_reconfigured_get_a2dp_cid(packet);
661 
662             if (status != ERROR_CODE_SUCCESS){
663                 printf("A2DP Source: Stream reconfiguration failed with status 0x%02x\n", status);
664                 break;
665             }
666 
667             printf("A2DP Source: Stream reconfigured a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
668             a2dp_demo_hexcmod_configure_sample_rate(new_sample_rate);
669             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
670             break;
671 
672         case A2DP_SUBEVENT_STREAM_STARTED:
673             local_seid = a2dp_subevent_stream_started_get_local_seid(packet);
674             cid = a2dp_subevent_stream_started_get_a2dp_cid(packet);
675 
676             play_info.status = AVRCP_PLAYBACK_STATUS_PLAYING;
677             if (media_tracker.avrcp_cid){
678                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
679                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PLAYING);
680             }
681             a2dp_demo_timer_start(&media_tracker);
682             printf("A2DP Source: Stream started, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
683             break;
684 
685         case A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
686             local_seid = a2dp_subevent_streaming_can_send_media_packet_now_get_local_seid(packet);
687             cid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_a2dp_cid(packet);
688             a2dp_demo_send_media_packet();
689             break;
690 
691         case A2DP_SUBEVENT_STREAM_SUSPENDED:
692             local_seid = a2dp_subevent_stream_suspended_get_local_seid(packet);
693             cid = a2dp_subevent_stream_suspended_get_a2dp_cid(packet);
694 
695             play_info.status = AVRCP_PLAYBACK_STATUS_PAUSED;
696             if (media_tracker.avrcp_cid){
697                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PAUSED);
698             }
699             printf("A2DP Source: Stream paused, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
700 
701             a2dp_demo_timer_stop(&media_tracker);
702             break;
703 
704         case A2DP_SUBEVENT_STREAM_RELEASED:
705             play_info.status = AVRCP_PLAYBACK_STATUS_STOPPED;
706             cid = a2dp_subevent_stream_released_get_a2dp_cid(packet);
707             local_seid = a2dp_subevent_stream_released_get_local_seid(packet);
708 
709             printf("A2DP Source: Stream released, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
710 
711             if (cid == media_tracker.a2dp_cid) {
712                 media_tracker.stream_opened = 0;
713                 printf("A2DP Source: Stream released.\n");
714             }
715             if (media_tracker.avrcp_cid){
716                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
717                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_STOPPED);
718             }
719             a2dp_demo_timer_stop(&media_tracker);
720             break;
721         case A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
722             cid = a2dp_subevent_signaling_connection_released_get_a2dp_cid(packet);
723             if (cid == media_tracker.a2dp_cid) {
724                 media_tracker.avrcp_cid = 0;
725                 media_tracker.a2dp_cid = 0;
726                 printf("A2DP Source: Signaling released.\n\n");
727             }
728             break;
729         default:
730             break;
731     }
732 }
733 
734 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
735     UNUSED(channel);
736     UNUSED(size);
737     bd_addr_t event_addr;
738     uint16_t local_cid;
739     uint8_t  status = ERROR_CODE_SUCCESS;
740 
741     if (packet_type != HCI_EVENT_PACKET) return;
742     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
743 
744     switch (packet[2]){
745         case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED:
746             local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
747             status = avrcp_subevent_connection_established_get_status(packet);
748             if (status != ERROR_CODE_SUCCESS){
749                 printf("AVRCP: Connection failed, local cid 0x%02x, status 0x%02x\n", local_cid, status);
750                 return;
751             }
752             media_tracker.avrcp_cid = local_cid;
753             avrcp_subevent_connection_established_get_bd_addr(packet, event_addr);
754 
755             printf("AVRCP: Channel to %s successfully opened, avrcp_cid 0x%02x\n", bd_addr_to_str(event_addr), media_tracker.avrcp_cid);
756 
757             avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
758 
759             printf("Enable Volume Change notification\n");
760             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED);
761             printf("Enable Battery Status Change notification\n");
762             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_BATT_STATUS_CHANGED);
763             return;
764 
765         case AVRCP_SUBEVENT_CONNECTION_RELEASED:
766             printf("AVRCP Target: Disconnected, avrcp_cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
767             media_tracker.avrcp_cid = 0;
768             return;
769         default:
770             break;
771     }
772 
773     if (status != ERROR_CODE_SUCCESS){
774         printf("Responding to event 0x%02x failed with status 0x%02x\n", packet[2], status);
775     }
776 }
777 
778 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
779     UNUSED(channel);
780     UNUSED(size);
781     uint8_t  status = ERROR_CODE_SUCCESS;
782 
783     if (packet_type != HCI_EVENT_PACKET) return;
784     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
785 
786     bool button_pressed;
787     char const * button_state;
788     avrcp_operation_id_t operation_id;
789 
790     switch (packet[2]){
791         case AVRCP_SUBEVENT_EVENT_IDS_QUERY:
792             status = avrcp_target_supported_events(media_tracker.avrcp_cid, events_num, events, sizeof(events));
793             break;
794         case AVRCP_SUBEVENT_COMPANY_IDS_QUERY:
795             status = avrcp_target_supported_companies(media_tracker.avrcp_cid, companies_num, companies, sizeof(companies));
796             break;
797         case AVRCP_SUBEVENT_PLAY_STATUS_QUERY:
798             status = avrcp_target_play_status(media_tracker.avrcp_cid, play_info.song_length_ms, play_info.song_position_ms, play_info.status);
799             break;
800         // case AVRCP_SUBEVENT_NOW_PLAYING_INFO_QUERY:
801         //     status = avrcp_target_now_playing_info(avrcp_cid);
802         //     break;
803         case AVRCP_SUBEVENT_OPERATION:
804             operation_id = avrcp_subevent_operation_get_operation_id(packet);
805             button_pressed = avrcp_subevent_operation_get_button_pressed(packet) > 0;
806             button_state = button_pressed ? "PRESS" : "RELEASE";
807 
808             printf("AVRCP Target: operation %s (%s)\n", avrcp_operation2str(operation_id), button_state);
809 
810             if (!button_pressed){
811                 break;
812             }
813             switch (operation_id) {
814                 case AVRCP_OPERATION_ID_PLAY:
815                     status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
816                     break;
817                 case AVRCP_OPERATION_ID_PAUSE:
818                     status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
819                     break;
820                 case AVRCP_OPERATION_ID_STOP:
821                     status = a2dp_source_disconnect(media_tracker.a2dp_cid);
822                     break;
823                 default:
824                     break;
825             }
826             break;
827         default:
828             break;
829     }
830 
831     if (status != ERROR_CODE_SUCCESS){
832         printf("Responding to event 0x%02x failed with status 0x%02x\n", packet[2], status);
833     }
834 }
835 
836 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
837     UNUSED(channel);
838     UNUSED(size);
839 
840     if (packet_type != HCI_EVENT_PACKET) return;
841     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
842     if (!media_tracker.avrcp_cid) return;
843 
844     switch (packet[2]){
845         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
846             printf("AVRCP Controller: Notification Absolute Volume %d %%\n", avrcp_subevent_notification_volume_changed_get_absolute_volume(packet) * 100 / 127);
847             break;
848         case AVRCP_SUBEVENT_NOTIFICATION_EVENT_BATT_STATUS_CHANGED:
849             // see avrcp_battery_status_t
850             printf("AVRCP Controller: Notification Battery Status %d\n", avrcp_subevent_notification_event_batt_status_changed_get_battery_status(packet));
851             break;
852         case AVRCP_SUBEVENT_ENABLE_NOTIFICATION_COMPLETE:
853             printf("AVRCP Controller: Notification %s ", avrcp_event2str(avrcp_subevent_enable_notification_complete_get_event_id(packet)));
854             if (avrcp_subevent_enable_notification_complete_get_status(packet) == ERROR_CODE_SUCCESS){
855                 printf("enabled\n");
856             } else {
857                 printf("disabled\n");
858             }
859 
860             break;
861         default:
862             break;
863     }
864 }
865 
866 #ifdef HAVE_BTSTACK_STDIN
867 static void show_usage(void){
868     bd_addr_t      iut_address;
869     gap_local_bd_addr(iut_address);
870     printf("\n--- Bluetooth  A2DP Source/AVRCP Demo %s ---\n", bd_addr_to_str(iut_address));
871     printf("b      - A2DP Source create connection to addr %s\n", device_addr_string);
872     printf("B      - A2DP Source disconnect\n");
873     printf("c      - AVRCP create connection to addr %s\n", device_addr_string);
874     printf("C      - AVRCP disconnect\n");
875     printf("D      - delete all link keys\n");
876 
877     printf("x      - start streaming sine\n");
878     if (hxcmod_initialized){
879         printf("z      - start streaming '%s'\n", mod_name);
880     }
881     printf("p      - pause streaming\n");
882     printf("w      - reconfigure stream for 44100 Hz\n");
883     printf("e      - reconfigure stream for 48000 Hz\n");
884     printf("t      - volume up\n");
885     printf("T      - volume down\n");
886     printf("v      - volume up (via set absolute volume)\n");
887     printf("V      - volume down (via set absolute volume)\n");
888 
889     printf("---\n");
890 }
891 
892 static void stdin_process(char cmd){
893     uint8_t status = ERROR_CODE_SUCCESS;
894     switch (cmd){
895         case 'b':
896             status = a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
897             printf("%c - Create A2DP Source connection to addr %s, cid 0x%02x.\n", cmd, bd_addr_to_str(device_addr), media_tracker.a2dp_cid);
898             break;
899         case 'B':
900             printf("%c - A2DP Source Disconnect from cid 0x%2x\n", cmd, media_tracker.a2dp_cid);
901             status = a2dp_source_disconnect(media_tracker.a2dp_cid);
902             break;
903         case 'c':
904             printf("%c - Create AVRCP connection to addr %s.\n", cmd, bd_addr_to_str(device_addr));
905             status = avrcp_connect(device_addr, &media_tracker.avrcp_cid);
906             break;
907         case 'C':
908             printf("%c - AVRCP disconnect\n", cmd);
909             status = avrcp_disconnect(media_tracker.avrcp_cid);
910             break;
911         case 'D':
912             printf("Deleting all link keys\n");
913             gap_delete_all_link_keys();
914             break;
915         case '\n':
916         case '\r':
917             break;
918 
919         case 't':
920             printf(" - volume up\n");
921             status = avrcp_controller_volume_up(media_tracker.avrcp_cid);
922             break;
923         case 'T':
924             printf(" - volume down\n");
925             status = avrcp_controller_volume_down(media_tracker.avrcp_cid);
926             break;
927 
928         case 'v':
929             if (media_tracker.volume > 117){
930                 media_tracker.volume = 127;
931             } else {
932                 media_tracker.volume += 10;
933             }
934             printf(" - volume up (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
935             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
936             break;
937         case 'V':
938             if (media_tracker.volume < 10){
939                 media_tracker.volume = 0;
940             } else {
941                 media_tracker.volume -= 10;
942             }
943             printf(" - volume down (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
944             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
945             break;
946 
947         case 'x':
948             if (media_tracker.avrcp_cid){
949                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
950             }
951             printf("%c - Play sine.\n", cmd);
952             data_source = STREAM_SINE;
953             if (!media_tracker.stream_opened) break;
954             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
955             break;
956         case 'z':
957             if (media_tracker.avrcp_cid){
958                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
959             }
960             printf("%c - Play mod.\n", cmd);
961             data_source = STREAM_MOD;
962             if (!media_tracker.stream_opened) break;
963             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
964             break;
965 
966         case 'p':
967             if (!media_tracker.stream_opened) break;
968             printf("%c - Pause stream.\n", cmd);
969             status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
970             break;
971 
972         case 'w':
973             if (!media_tracker.stream_opened) break;
974             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
975                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
976                 break;
977             }
978             new_sample_rate = 44100;
979             if (current_sample_rate == new_sample_rate){
980                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
981             } else {
982                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
983                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
984             }
985             break;
986 
987         case 'e':
988             if (!media_tracker.stream_opened) break;
989             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
990                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
991                 break;
992             }
993             new_sample_rate = 48000;
994             if (current_sample_rate == new_sample_rate){
995                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
996             } else {
997                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
998                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
999             }
1000             break;
1001 
1002         default:
1003             show_usage();
1004             return;
1005     }
1006     if (status != ERROR_CODE_SUCCESS){
1007         printf("Could not perform command \'%c\', status 0x%02x\n", cmd, status);
1008     }
1009 }
1010 #endif
1011 
1012 
1013 int btstack_main(int argc, const char * argv[]);
1014 int btstack_main(int argc, const char * argv[]){
1015     (void)argc;
1016     (void)argv;
1017 
1018     int err = a2dp_source_and_avrcp_services_init();
1019     if (err) return err;
1020     // turn on!
1021     hci_power_control(HCI_POWER_ON);
1022     return 0;
1023 }
1024 /* EXAMPLE_END */
1025