xref: /btstack/example/a2dp_source_demo.c (revision 42c5c5581b83a00e2c1de42e4fe687a30b9efa5a)
1 /*
2  * Copyright (C) 2016 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "a2dp_source_demo.c"
39 
40 /*
41  * a2dp_source_demo.c
42  */
43 
44 // *****************************************************************************
45 /* EXAMPLE_START(a2dp_source_demo): A2DP Source - Stream Audio and Control Volume
46  *
47  * @text This A2DP Source example demonstrates how to send an audio data stream
48  * to a remote A2DP Sink device and how to switch between two audio data sources.
49  * In addition, the AVRCP Target is used to answer queries on currently played media,
50  * as well as to handle remote playback control, i.e. play, stop, repeat, etc. If HAVE_BTSTACK_STDIN
51  * is set, press SPACE on the console to show the available AVDTP and AVRCP commands.
52  *
53  * @text To test with a remote device, e.g. a Bluetooth speaker,
54  * set the device_addr_string to the Bluetooth address of your
55  * remote device in the code, and use the UI to connect and start playback.
56  *
57  * @text For more info on BTstack audio, see our blog post
58  * [A2DP Sink and Source on STM32 F4 Discovery Board](http://bluekitchen-gmbh.com/a2dp-sink-and-source-on-stm32-f4-discovery-board/).
59  *
60  */
61 // *****************************************************************************
62 
63 
64 #include <stdint.h>
65 #include <stdio.h>
66 #include <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     uint8_t volume;
110 } a2dp_media_sending_context_t;
111 
112 static  uint8_t media_sbc_codec_capabilities[] = {
113     (AVDTP_SBC_44100 << 4) | AVDTP_SBC_STEREO,
114     0xFF,//(AVDTP_SBC_BLOCK_LENGTH_16 << 4) | (AVDTP_SBC_SUBBANDS_8 << 2) | AVDTP_SBC_ALLOCATION_METHOD_LOUDNESS,
115     2, 53
116 };
117 
118 // input signal: pre-computed int16 sine wave, 44100 Hz at 441 Hz
119 static const int16_t sine_int16_44100[] = {
120      0,    2057,    4107,    6140,    8149,   10126,   12062,   13952,   15786,   17557,
121  19260,   20886,   22431,   23886,   25247,   26509,   27666,   28714,   29648,   30466,
122  31163,   31738,   32187,   32509,   32702,   32767,   32702,   32509,   32187,   31738,
123  31163,   30466,   29648,   28714,   27666,   26509,   25247,   23886,   22431,   20886,
124  19260,   17557,   15786,   13952,   12062,   10126,    8149,    6140,    4107,    2057,
125      0,   -2057,   -4107,   -6140,   -8149,  -10126,  -12062,  -13952,  -15786,  -17557,
126 -19260,  -20886,  -22431,  -23886,  -25247,  -26509,  -27666,  -28714,  -29648,  -30466,
127 -31163,  -31738,  -32187,  -32509,  -32702,  -32767,  -32702,  -32509,  -32187,  -31738,
128 -31163,  -30466,  -29648,  -28714,  -27666,  -26509,  -25247,  -23886,  -22431,  -20886,
129 -19260,  -17557,  -15786,  -13952,  -12062,  -10126,   -8149,   -6140,   -4107,   -2057,
130 };
131 
132 static const int num_samples_sine_int16_44100 = sizeof(sine_int16_44100) / 2;
133 
134 // input signal: pre-computed int16 sine wave, 48000 Hz at 441 Hz
135 static const int16_t sine_int16_48000[] = {
136      0,    1905,    3804,    5690,    7557,    9398,   11207,   12978,   14706,   16383,
137  18006,   19567,   21062,   22486,   23834,   25101,   26283,   27376,   28377,   29282,
138  30087,   30791,   31390,   31884,   32269,   32545,   32712,   32767,   32712,   32545,
139  32269,   31884,   31390,   30791,   30087,   29282,   28377,   27376,   26283,   25101,
140  23834,   22486,   21062,   19567,   18006,   16383,   14706,   12978,   11207,    9398,
141   7557,    5690,    3804,    1905,       0,   -1905,   -3804,   -5690,   -7557,   -9398,
142 -11207,  -12978,  -14706,  -16384,  -18006,  -19567,  -21062,  -22486,  -23834,  -25101,
143 -26283,  -27376,  -28377,  -29282,  -30087,  -30791,  -31390,  -31884,  -32269,  -32545,
144 -32712,  -32767,  -32712,  -32545,  -32269,  -31884,  -31390,  -30791,  -30087,  -29282,
145 -28377,  -27376,  -26283,  -25101,  -23834,  -22486,  -21062,  -19567,  -18006,  -16384,
146 -14706,  -12978,  -11207,   -9398,   -7557,   -5690,   -3804,   -1905,  };
147 
148 static const int num_samples_sine_int16_48000 = sizeof(sine_int16_48000) / 2;
149 
150 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 
204 typedef struct {
205     uint8_t track_id[8];
206     uint32_t song_length_ms;
207     avrcp_playback_status_t status;
208     uint32_t song_position_ms; // 0xFFFFFFFF if not supported
209 } avrcp_play_status_info_t;
210 
211 // python -c "print('a'*512)"
212 static const char title[] = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
213 
214 avrcp_track_t tracks[] = {
215     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}, 1, "Sine", "Generated", "A2DP Source Demo", "monotone", 12345},
216     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}, 2, "Nao-deceased", "Decease", "A2DP Source Demo", "vivid", 12345},
217     {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03}, 3, (char *)title, "Decease", "A2DP Source Demo", "vivid", 12345},
218 };
219 int current_track_index;
220 avrcp_play_status_info_t play_info;
221 
222 /* AVRCP Target context END */
223 
224 /* @section Main Application Setup
225  *
226  * @text The Listing MainConfiguration shows how to setup AD2P Source and AVRCP services.
227  * Besides calling init() method for each service, you'll also need to register several packet handlers:
228  * - hci_packet_handler - handles legacy pairing, here by using fixed '0000' pin code.
229  * - 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).
230  * - avrcp_packet_handler - receives connect/disconnect event.
231  * - avrcp_controller_packet_handler - receives answers for sent AVRCP commands.
232  * - avrcp_target_packet_handler - receives AVRCP commands, and registered notifications.
233  * - 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.
234  *
235  * @text To announce A2DP Source and AVRCP services, you need to create corresponding
236  * SDP records and register them with the SDP service.
237  */
238 
239 /* LISTING_START(MainConfiguration): Setup Audio Source and AVRCP Target services */
240 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
241 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * event, uint16_t event_size);
242 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
243 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
244 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
245 #ifdef HAVE_BTSTACK_STDIN
246 static void stdin_process(char cmd);
247 #endif
248 
249 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate);
250 
251 static int a2dp_source_and_avrcp_services_init(void){
252 
253     // Request role change on reconnecting headset to always use them in slave mode
254     hci_set_master_slave_policy(0);
255 
256     l2cap_init();
257 
258 #ifdef ENABLE_BLE
259     // Initialize LE Security Manager. Needed for cross-transport key derivation
260     sm_init();
261 #endif
262 
263     // Initialize  A2DP Source
264     a2dp_source_init();
265     a2dp_source_register_packet_handler(&a2dp_source_packet_handler);
266 
267     // Create stream endpoint
268     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));
269     if (!local_stream_endpoint){
270         printf("A2DP Source: not enough memory to create local stream endpoint\n");
271         return 1;
272     }
273 
274     // Store stream enpoint's SEP ID, as it is used by A2DP API to indentify the stream endpoint
275     media_tracker.local_seid = avdtp_local_seid(local_stream_endpoint);
276     avdtp_source_register_delay_reporting_category(media_tracker.local_seid);
277 
278     // Initialize AVRCP Service
279     avrcp_init();
280     avrcp_register_packet_handler(&avrcp_packet_handler);
281     // Initialize AVRCP Target
282     avrcp_target_init();
283     avrcp_target_register_packet_handler(&avrcp_target_packet_handler);
284 
285     // Initialize AVRCP Controller
286     avrcp_controller_init();
287     avrcp_controller_register_packet_handler(&avrcp_controller_packet_handler);
288 
289     // Initialize SDP,
290     sdp_init();
291 
292     // Create A2DP Source service record and register it with SDP
293     memset(sdp_a2dp_source_service_buffer, 0, sizeof(sdp_a2dp_source_service_buffer));
294     a2dp_source_create_sdp_record(sdp_a2dp_source_service_buffer, 0x10001, AVDTP_SOURCE_FEATURE_MASK_PLAYER, NULL, NULL);
295     sdp_register_service(sdp_a2dp_source_service_buffer);
296 
297     // Create AVRCP Target service record and register it with SDP. We receive Category 1 commands from the headphone, e.g. play/pause
298     memset(sdp_avrcp_target_service_buffer, 0, sizeof(sdp_avrcp_target_service_buffer));
299     uint16_t supported_features = AVRCP_FEATURE_MASK_CATEGORY_PLAYER_OR_RECORDER;
300 #ifdef AVRCP_BROWSING_ENABLED
301     supported_features |= AVRCP_FEATURE_MASK_BROWSING;
302 #endif
303     avrcp_target_create_sdp_record(sdp_avrcp_target_service_buffer, 0x10002, supported_features, NULL, NULL);
304     sdp_register_service(sdp_avrcp_target_service_buffer);
305 
306     // Create AVRCP Controller service record and register it with SDP. We send Category 2 commands to the headphone, e.g. volume up/down
307     memset(sdp_avrcp_controller_service_buffer, 0, sizeof(sdp_avrcp_controller_service_buffer));
308     uint16_t controller_supported_features = AVRCP_FEATURE_MASK_CATEGORY_MONITOR_OR_AMPLIFIER;
309     avrcp_controller_create_sdp_record(sdp_avrcp_controller_service_buffer, 0x10003, controller_supported_features, NULL, NULL);
310     sdp_register_service(sdp_avrcp_controller_service_buffer);
311 
312     // Register Device ID (PnP) service SDP record
313     memset(device_id_sdp_service_buffer, 0, sizeof(device_id_sdp_service_buffer));
314     device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10004, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1);
315     sdp_register_service(device_id_sdp_service_buffer);
316 
317     // Set local name with a template Bluetooth address, that will be automatically
318     // replaced with a actual address once it is available, i.e. when BTstack boots
319     // up and starts talking to a Bluetooth module.
320     gap_set_local_name("A2DP Source 00:00:00:00:00:00");
321     gap_discoverable_control(1);
322     gap_set_class_of_device(0x200408);
323 
324     // Register for HCI events.
325     hci_event_callback_registration.callback = &hci_packet_handler;
326     hci_add_event_handler(&hci_event_callback_registration);
327 
328     a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
329     data_source = STREAM_MOD;
330 
331     // Parse human readable Bluetooth address.
332     sscanf_bd_addr(device_addr_string, device_addr);
333 
334 #ifdef HAVE_BTSTACK_STDIN
335     btstack_stdin_setup(stdin_process);
336 #endif
337     return 0;
338 }
339 /* LISTING_END */
340 
341 static void a2dp_demo_hexcmod_configure_sample_rate(int sample_rate){
342     if (!hxcmod_initialized){
343         hxcmod_initialized = hxcmod_init(&mod_context);
344         if (!hxcmod_initialized) {
345             printf("could not initialize hxcmod\n");
346             return;
347         }
348     }
349     current_sample_rate = sample_rate;
350     media_tracker.sbc_storage_count = 0;
351     media_tracker.samples_ready = 0;
352     hxcmod_unload(&mod_context);
353     hxcmod_setcfg(&mod_context, current_sample_rate, 16, 1, 1, 1);
354     hxcmod_load(&mod_context, (void *) &mod_data, mod_len);
355 }
356 
357 static void a2dp_demo_send_media_packet(void){
358     int num_bytes_in_frame = btstack_sbc_encoder_sbc_buffer_length();
359     int bytes_in_storage = media_tracker.sbc_storage_count;
360     uint8_t num_frames = bytes_in_storage / num_bytes_in_frame;
361     // Prepend SBC Header
362     media_tracker.sbc_storage[0] = num_frames;  // (fragmentation << 7) | (starting_packet << 6) | (last_packet << 5) | num_frames;
363     avdtp_source_stream_send_media_payload_rtp(media_tracker.a2dp_cid, media_tracker.local_seid, 0, media_tracker.sbc_storage, bytes_in_storage + 1);
364 
365     media_tracker.sbc_storage_count = 0;
366     media_tracker.sbc_ready_to_send = 0;
367 }
368 
369 static void produce_sine_audio(int16_t * pcm_buffer, int num_samples_to_write){
370     int count;
371     for (count = 0; count < num_samples_to_write ; count++){
372         switch (current_sample_rate){
373             case 44100:
374                 pcm_buffer[count * 2]     = sine_int16_44100[sine_phase];
375                 pcm_buffer[count * 2 + 1] = sine_int16_44100[sine_phase];
376                 sine_phase++;
377                 if (sine_phase >= num_samples_sine_int16_44100){
378                     sine_phase -= num_samples_sine_int16_44100;
379                 }
380                 break;
381             case 48000:
382                 pcm_buffer[count * 2]     = sine_int16_48000[sine_phase];
383                 pcm_buffer[count * 2 + 1] = sine_int16_48000[sine_phase];
384                 sine_phase++;
385                 if (sine_phase >= num_samples_sine_int16_48000){
386                     sine_phase -= num_samples_sine_int16_48000;
387                 }
388                 break;
389             default:
390                 break;
391         }
392     }
393 }
394 
395 static void produce_mod_audio(int16_t * pcm_buffer, int num_samples_to_write){
396     hxcmod_fillbuffer(&mod_context, (unsigned short *) &pcm_buffer[0], num_samples_to_write, &trkbuf);
397 }
398 
399 static void produce_audio(int16_t * pcm_buffer, int num_samples){
400     switch (data_source){
401         case STREAM_SINE:
402             produce_sine_audio(pcm_buffer, num_samples);
403             break;
404         case STREAM_MOD:
405             produce_mod_audio(pcm_buffer, num_samples);
406             break;
407         default:
408             break;
409     }
410 #ifdef VOLUME_REDUCTION
411     int i;
412     for (i=0;i<num_samples*2;i++){
413         if (pcm_buffer[i] > 0){
414             pcm_buffer[i] =     pcm_buffer[i]  >> VOLUME_REDUCTION;
415         } else {
416             pcm_buffer[i] = -((-pcm_buffer[i]) >> VOLUME_REDUCTION);
417         }
418     }
419 #endif
420 }
421 
422 static int a2dp_demo_fill_sbc_audio_buffer(a2dp_media_sending_context_t * context){
423     // perform sbc encoding
424     int total_num_bytes_read = 0;
425     unsigned int num_audio_samples_per_sbc_buffer = btstack_sbc_encoder_num_audio_frames();
426     while (context->samples_ready >= num_audio_samples_per_sbc_buffer
427         && (context->max_media_payload_size - context->sbc_storage_count) >= btstack_sbc_encoder_sbc_buffer_length()){
428 
429         int16_t pcm_frame[256*NUM_CHANNELS];
430 
431         produce_audio(pcm_frame, num_audio_samples_per_sbc_buffer);
432         btstack_sbc_encoder_process_data(pcm_frame);
433 
434         uint16_t sbc_frame_size = btstack_sbc_encoder_sbc_buffer_length();
435         uint8_t * sbc_frame = btstack_sbc_encoder_sbc_buffer();
436 
437         total_num_bytes_read += num_audio_samples_per_sbc_buffer;
438         // first byte in sbc storage contains sbc media header
439         memcpy(&context->sbc_storage[1 + context->sbc_storage_count], sbc_frame, sbc_frame_size);
440         context->sbc_storage_count += sbc_frame_size;
441         context->samples_ready -= num_audio_samples_per_sbc_buffer;
442     }
443     return total_num_bytes_read;
444 }
445 
446 static void a2dp_demo_audio_timeout_handler(btstack_timer_source_t * timer){
447     a2dp_media_sending_context_t * context = (a2dp_media_sending_context_t *) btstack_run_loop_get_timer_context(timer);
448     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
449     btstack_run_loop_add_timer(&context->audio_timer);
450     uint32_t now = btstack_run_loop_get_time_ms();
451 
452     uint32_t update_period_ms = AUDIO_TIMEOUT_MS;
453     if (context->time_audio_data_sent > 0){
454         update_period_ms = now - context->time_audio_data_sent;
455     }
456 
457     uint32_t num_samples = (update_period_ms * current_sample_rate) / 1000;
458     context->acc_num_missed_samples += (update_period_ms * current_sample_rate) % 1000;
459 
460     while (context->acc_num_missed_samples >= 1000){
461         num_samples++;
462         context->acc_num_missed_samples -= 1000;
463     }
464     context->time_audio_data_sent = now;
465     context->samples_ready += num_samples;
466 
467     if (context->sbc_ready_to_send) return;
468 
469     a2dp_demo_fill_sbc_audio_buffer(context);
470 
471     if ((context->sbc_storage_count + btstack_sbc_encoder_sbc_buffer_length()) > context->max_media_payload_size){
472         // schedule sending
473         context->sbc_ready_to_send = 1;
474         a2dp_source_stream_endpoint_request_can_send_now(context->a2dp_cid, context->local_seid);
475     }
476 }
477 
478 static void a2dp_demo_timer_start(a2dp_media_sending_context_t * context){
479     context->max_media_payload_size = btstack_min(a2dp_max_media_payload_size(context->a2dp_cid, context->local_seid), SBC_STORAGE_SIZE);
480     context->sbc_storage_count = 0;
481     context->sbc_ready_to_send = 0;
482     context->streaming = 1;
483     btstack_run_loop_remove_timer(&context->audio_timer);
484     btstack_run_loop_set_timer_handler(&context->audio_timer, a2dp_demo_audio_timeout_handler);
485     btstack_run_loop_set_timer_context(&context->audio_timer, context);
486     btstack_run_loop_set_timer(&context->audio_timer, AUDIO_TIMEOUT_MS);
487     btstack_run_loop_add_timer(&context->audio_timer);
488 }
489 
490 static void a2dp_demo_timer_stop(a2dp_media_sending_context_t * context){
491     context->time_audio_data_sent = 0;
492     context->acc_num_missed_samples = 0;
493     context->samples_ready = 0;
494     context->streaming = 1;
495     context->sbc_storage_count = 0;
496     context->sbc_ready_to_send = 0;
497     btstack_run_loop_remove_timer(&context->audio_timer);
498 }
499 
500 static void dump_sbc_configuration(media_codec_configuration_sbc_t * configuration){
501     printf("Received media codec configuration:\n");
502     printf("    - num_channels: %d\n", configuration->num_channels);
503     printf("    - sampling_frequency: %d\n", configuration->sampling_frequency);
504     printf("    - channel_mode: %d\n", configuration->channel_mode);
505     printf("    - block_length: %d\n", configuration->block_length);
506     printf("    - subbands: %d\n", configuration->subbands);
507     printf("    - allocation_method: %d\n", configuration->allocation_method);
508     printf("    - bitpool_value [%d, %d] \n", configuration->min_bitpool_value, configuration->max_bitpool_value);
509 }
510 
511 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
512     UNUSED(channel);
513     UNUSED(size);
514     if (packet_type != HCI_EVENT_PACKET) return;
515 
516 #ifndef HAVE_BTSTACK_STDIN
517     if (hci_event_packet_get_type(packet) == BTSTACK_EVENT_STATE){
518         if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) return;
519         printf("Create A2DP Source connection to addr %s.\n", bd_addr_to_str(device_addr));
520         uint8_t status = a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
521         if (status != ERROR_CODE_SUCCESS){
522             printf("Could not perform command, status 0x%2x\n", status);
523         }
524         return;
525     }
526 #endif
527 
528     if (hci_event_packet_get_type(packet) == HCI_EVENT_PIN_CODE_REQUEST) {
529         bd_addr_t address;
530         printf("Pin code request - using '0000'\n");
531         hci_event_pin_code_request_get_bd_addr(packet, address);
532         gap_pin_code_response(address, "0000");
533     }
534 }
535 
536 static void a2dp_source_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
537     UNUSED(channel);
538     UNUSED(size);
539     uint8_t status;
540     uint8_t local_seid;
541     bd_addr_t address;
542     uint16_t cid;
543 
544     avdtp_channel_mode_t channel_mode;
545     uint8_t allocation_method;
546 
547     if (packet_type != HCI_EVENT_PACKET) return;
548     if (hci_event_packet_get_type(packet) != HCI_EVENT_A2DP_META) return;
549 
550     switch (hci_event_a2dp_meta_get_subevent_code(packet)){
551         case A2DP_SUBEVENT_SIGNALING_CONNECTION_ESTABLISHED:
552             a2dp_subevent_signaling_connection_established_get_bd_addr(packet, address);
553             cid = a2dp_subevent_signaling_connection_established_get_a2dp_cid(packet);
554             status = a2dp_subevent_signaling_connection_established_get_status(packet);
555 
556             if (status != ERROR_CODE_SUCCESS){
557                 printf("A2DP Source: Connection failed, status 0x%02x, cid 0x%02x, a2dp_cid 0x%02x \n", status, cid, media_tracker.a2dp_cid);
558                 media_tracker.a2dp_cid = 0;
559                 break;
560             }
561             media_tracker.a2dp_cid = cid;
562             media_tracker.volume = 32;
563 
564             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);
565             break;
566 
567          case A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION:{
568             cid  = avdtp_subevent_signaling_media_codec_sbc_configuration_get_avdtp_cid(packet);
569             if (cid != media_tracker.a2dp_cid) return;
570 
571             media_tracker.remote_seid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet);
572 
573             sbc_configuration.reconfigure = a2dp_subevent_signaling_media_codec_sbc_configuration_get_reconfigure(packet);
574             sbc_configuration.num_channels = a2dp_subevent_signaling_media_codec_sbc_configuration_get_num_channels(packet);
575             sbc_configuration.sampling_frequency = a2dp_subevent_signaling_media_codec_sbc_configuration_get_sampling_frequency(packet);
576             sbc_configuration.block_length = a2dp_subevent_signaling_media_codec_sbc_configuration_get_block_length(packet);
577             sbc_configuration.subbands = a2dp_subevent_signaling_media_codec_sbc_configuration_get_subbands(packet);
578             sbc_configuration.min_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_min_bitpool_value(packet);
579             sbc_configuration.max_bitpool_value = a2dp_subevent_signaling_media_codec_sbc_configuration_get_max_bitpool_value(packet);
580 
581             channel_mode = (avdtp_channel_mode_t) a2dp_subevent_signaling_media_codec_sbc_configuration_get_channel_mode(packet);
582             allocation_method = a2dp_subevent_signaling_media_codec_sbc_configuration_get_allocation_method(packet);
583 
584             printf("A2DP Source: Received SBC codec configuration, sampling frequency %u, a2dp_cid 0x%02x, local seid 0x%02x, remote seid 0x%02x.\n",
585                 sbc_configuration.sampling_frequency, cid,
586                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_local_seid(packet),
587                    a2dp_subevent_signaling_media_codec_sbc_configuration_get_remote_seid(packet));
588 
589             // Adapt Bluetooth spec definition to SBC Encoder expected input
590             sbc_configuration.allocation_method = (btstack_sbc_allocation_method_t)(allocation_method - 1);
591             switch (channel_mode){
592                 case AVDTP_CHANNEL_MODE_JOINT_STEREO:
593                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_JOINT_STEREO;
594                     break;
595                 case AVDTP_CHANNEL_MODE_STEREO:
596                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_STEREO;
597                     break;
598                 case AVDTP_CHANNEL_MODE_DUAL_CHANNEL:
599                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_DUAL_CHANNEL;
600                     break;
601                 case AVDTP_CHANNEL_MODE_MONO:
602                     sbc_configuration.channel_mode = SBC_CHANNEL_MODE_MONO;
603                     break;
604                 default:
605                     btstack_assert(false);
606                     break;
607             }
608             dump_sbc_configuration(&sbc_configuration);
609 
610             btstack_sbc_encoder_init(&sbc_encoder_state, SBC_MODE_STANDARD,
611                 sbc_configuration.block_length, sbc_configuration.subbands,
612                 sbc_configuration.allocation_method, sbc_configuration.sampling_frequency,
613                 sbc_configuration.max_bitpool_value,
614                 sbc_configuration.channel_mode);
615             break;
616         }
617 
618         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORTING_CAPABILITY:
619             printf("A2DP Source: remote supports delay report, remote seid %d\n",
620                 avdtp_subevent_signaling_delay_reporting_capability_get_remote_seid(packet));
621             break;
622         case A2DP_SUBEVENT_SIGNALING_CAPABILITIES_DONE:
623             printf("A2DP Source: All capabilities reported, remote seid %d\n",
624                 avdtp_subevent_signaling_capabilities_done_get_remote_seid(packet));
625             break;
626 
627         case A2DP_SUBEVENT_SIGNALING_DELAY_REPORT:
628             printf("A2DP Source: Received delay report of %d.%0d ms, local seid %d\n",
629                 avdtp_subevent_signaling_delay_report_get_delay_100us(packet)/10, avdtp_subevent_signaling_delay_report_get_delay_100us(packet)%10,
630                 avdtp_subevent_signaling_delay_report_get_local_seid(packet));
631             break;
632 
633         case A2DP_SUBEVENT_STREAM_ESTABLISHED:
634             a2dp_subevent_stream_established_get_bd_addr(packet, address);
635             status = a2dp_subevent_stream_established_get_status(packet);
636             if (status != ERROR_CODE_SUCCESS){
637                 printf("A2DP Source: Stream failed, status 0x%02x.\n", status);
638                 break;
639             }
640 
641             local_seid = a2dp_subevent_stream_established_get_local_seid(packet);
642             cid = a2dp_subevent_stream_established_get_a2dp_cid(packet);
643 
644             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));
645 
646             a2dp_demo_hexcmod_configure_sample_rate(current_sample_rate);
647             media_tracker.stream_opened = 1;
648             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
649             break;
650 
651         case A2DP_SUBEVENT_STREAM_RECONFIGURED:
652             status = a2dp_subevent_stream_reconfigured_get_status(packet);
653             local_seid = a2dp_subevent_stream_reconfigured_get_local_seid(packet);
654             cid = a2dp_subevent_stream_reconfigured_get_a2dp_cid(packet);
655 
656             if (status != ERROR_CODE_SUCCESS){
657                 printf("A2DP Source: Stream reconfiguration failed with status 0x%02x\n", status);
658                 break;
659             }
660 
661             printf("A2DP Source: Stream reconfigured a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
662             a2dp_demo_hexcmod_configure_sample_rate(new_sample_rate);
663             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
664             break;
665 
666         case A2DP_SUBEVENT_STREAM_STARTED:
667             local_seid = a2dp_subevent_stream_started_get_local_seid(packet);
668             cid = a2dp_subevent_stream_started_get_a2dp_cid(packet);
669 
670             play_info.status = AVRCP_PLAYBACK_STATUS_PLAYING;
671             if (media_tracker.avrcp_cid){
672                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
673                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PLAYING);
674             }
675             a2dp_demo_timer_start(&media_tracker);
676             printf("A2DP Source: Stream started, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
677             break;
678 
679         case A2DP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW:
680             local_seid = a2dp_subevent_streaming_can_send_media_packet_now_get_local_seid(packet);
681             cid = a2dp_subevent_signaling_media_codec_sbc_configuration_get_a2dp_cid(packet);
682             a2dp_demo_send_media_packet();
683             break;
684 
685         case A2DP_SUBEVENT_STREAM_SUSPENDED:
686             local_seid = a2dp_subevent_stream_suspended_get_local_seid(packet);
687             cid = a2dp_subevent_stream_suspended_get_a2dp_cid(packet);
688 
689             play_info.status = AVRCP_PLAYBACK_STATUS_PAUSED;
690             if (media_tracker.avrcp_cid){
691                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_PAUSED);
692             }
693             printf("A2DP Source: Stream paused, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
694 
695             a2dp_demo_timer_stop(&media_tracker);
696             break;
697 
698         case A2DP_SUBEVENT_STREAM_RELEASED:
699             play_info.status = AVRCP_PLAYBACK_STATUS_STOPPED;
700             cid = a2dp_subevent_stream_released_get_a2dp_cid(packet);
701             local_seid = a2dp_subevent_stream_released_get_local_seid(packet);
702 
703             printf("A2DP Source: Stream released, a2dp_cid 0x%02x, local_seid 0x%02x\n", cid, local_seid);
704 
705             if (cid == media_tracker.a2dp_cid) {
706                 media_tracker.stream_opened = 0;
707                 printf("A2DP Source: Stream released.\n");
708             }
709             if (media_tracker.avrcp_cid){
710                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
711                 avrcp_target_set_playback_status(media_tracker.avrcp_cid, AVRCP_PLAYBACK_STATUS_STOPPED);
712             }
713             a2dp_demo_timer_stop(&media_tracker);
714             break;
715         case A2DP_SUBEVENT_SIGNALING_CONNECTION_RELEASED:
716             cid = a2dp_subevent_signaling_connection_released_get_a2dp_cid(packet);
717             if (cid == media_tracker.a2dp_cid) {
718                 media_tracker.avrcp_cid = 0;
719                 media_tracker.a2dp_cid = 0;
720                 printf("A2DP Source: Signaling released.\n\n");
721             }
722             break;
723         default:
724             break;
725     }
726 }
727 
728 static void avrcp_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
729     UNUSED(channel);
730     UNUSED(size);
731     bd_addr_t event_addr;
732     uint16_t local_cid;
733     uint8_t  status = ERROR_CODE_SUCCESS;
734 
735     if (packet_type != HCI_EVENT_PACKET) return;
736     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
737 
738     switch (packet[2]){
739         case AVRCP_SUBEVENT_CONNECTION_ESTABLISHED:
740             local_cid = avrcp_subevent_connection_established_get_avrcp_cid(packet);
741             status = avrcp_subevent_connection_established_get_status(packet);
742             if (status != ERROR_CODE_SUCCESS){
743                 printf("AVRCP: Connection failed, local cid 0x%02x, status 0x%02x\n", local_cid, status);
744                 return;
745             }
746             media_tracker.avrcp_cid = local_cid;
747             avrcp_subevent_connection_established_get_bd_addr(packet, event_addr);
748 
749             printf("AVRCP: Channel to %s successfully opened, avrcp_cid 0x%02x\n", bd_addr_to_str(event_addr), media_tracker.avrcp_cid);
750 
751             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_PLAYBACK_STATUS_CHANGED);
752             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_TRACK_CHANGED);
753             avrcp_target_support_event(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_NOW_PLAYING_CONTENT_CHANGED);
754             avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, NULL, sizeof(tracks)/sizeof(avrcp_track_t));
755 
756             printf("Enable Volume Change notification\n");
757             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_VOLUME_CHANGED);
758             printf("Enable Battery Status Change notification\n");
759             avrcp_controller_enable_notification(media_tracker.avrcp_cid, AVRCP_NOTIFICATION_EVENT_BATT_STATUS_CHANGED);
760             return;
761 
762         case AVRCP_SUBEVENT_CONNECTION_RELEASED:
763             printf("AVRCP Target: Disconnected, avrcp_cid 0x%02x\n", avrcp_subevent_connection_released_get_avrcp_cid(packet));
764             media_tracker.avrcp_cid = 0;
765             return;
766         default:
767             break;
768     }
769 
770     if (status != ERROR_CODE_SUCCESS){
771         printf("Responding to event 0x%02x failed with status 0x%02x\n", packet[2], status);
772     }
773 }
774 
775 static void avrcp_target_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
776     UNUSED(channel);
777     UNUSED(size);
778     uint8_t  status = ERROR_CODE_SUCCESS;
779 
780     if (packet_type != HCI_EVENT_PACKET) return;
781     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
782 
783     bool button_pressed;
784     char const * button_state;
785     avrcp_operation_id_t operation_id;
786 
787     switch (packet[2]){
788         case AVRCP_SUBEVENT_PLAY_STATUS_QUERY:
789             status = avrcp_target_play_status(media_tracker.avrcp_cid, play_info.song_length_ms, play_info.song_position_ms, play_info.status);
790             break;
791         // case AVRCP_SUBEVENT_NOW_PLAYING_INFO_QUERY:
792         //     status = avrcp_target_now_playing_info(avrcp_cid);
793         //     break;
794         case AVRCP_SUBEVENT_OPERATION:
795             operation_id = avrcp_subevent_operation_get_operation_id(packet);
796             button_pressed = avrcp_subevent_operation_get_button_pressed(packet) > 0;
797             button_state = button_pressed ? "PRESS" : "RELEASE";
798 
799             printf("AVRCP Target: operation %s (%s)\n", avrcp_operation2str(operation_id), button_state);
800 
801             if (!button_pressed){
802                 break;
803             }
804             switch (operation_id) {
805                 case AVRCP_OPERATION_ID_PLAY:
806                     status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
807                     break;
808                 case AVRCP_OPERATION_ID_PAUSE:
809                     status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
810                     break;
811                 case AVRCP_OPERATION_ID_STOP:
812                     status = a2dp_source_disconnect(media_tracker.a2dp_cid);
813                     break;
814                 default:
815                     break;
816             }
817             break;
818         default:
819             break;
820     }
821 
822     if (status != ERROR_CODE_SUCCESS){
823         printf("Responding to event 0x%02x failed with status 0x%02x\n", packet[2], status);
824     }
825 }
826 
827 static void avrcp_controller_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
828     UNUSED(channel);
829     UNUSED(size);
830 
831     if (packet_type != HCI_EVENT_PACKET) return;
832     if (hci_event_packet_get_type(packet) != HCI_EVENT_AVRCP_META) return;
833     if (!media_tracker.avrcp_cid) return;
834 
835     switch (packet[2]){
836         case AVRCP_SUBEVENT_NOTIFICATION_VOLUME_CHANGED:
837             printf("AVRCP Controller: Notification Absolute Volume %d %%\n", avrcp_subevent_notification_volume_changed_get_absolute_volume(packet) * 100 / 127);
838             break;
839         case AVRCP_SUBEVENT_NOTIFICATION_EVENT_BATT_STATUS_CHANGED:
840             // see avrcp_battery_status_t
841             printf("AVRCP Controller: Notification Battery Status %d\n", avrcp_subevent_notification_event_batt_status_changed_get_battery_status(packet));
842             break;
843         case AVRCP_SUBEVENT_NOTIFICATION_STATE:
844             printf("AVRCP Controller: Notification %s - %s\n",
845                 avrcp_event2str(avrcp_subevent_notification_state_get_event_id(packet)),
846                 avrcp_subevent_notification_state_get_enabled(packet) != 0 ? "enabled" : "disabled");
847             break;
848         default:
849             break;
850     }
851 }
852 
853 #ifdef HAVE_BTSTACK_STDIN
854 static void show_usage(void){
855     bd_addr_t      iut_address;
856     gap_local_bd_addr(iut_address);
857     printf("\n--- Bluetooth  A2DP Source/AVRCP Demo %s ---\n", bd_addr_to_str(iut_address));
858     printf("b      - A2DP Source create connection to addr %s\n", device_addr_string);
859     printf("B      - A2DP Source disconnect\n");
860     printf("c      - AVRCP create connection to addr %s\n", device_addr_string);
861     printf("C      - AVRCP disconnect\n");
862     printf("D      - delete all link keys\n");
863 
864     printf("x      - start streaming sine\n");
865     if (hxcmod_initialized){
866         printf("z      - start streaming '%s'\n", mod_name);
867     }
868     printf("p      - pause streaming\n");
869     printf("w      - reconfigure stream for 44100 Hz\n");
870     printf("e      - reconfigure stream for 48000 Hz\n");
871     printf("t      - volume up\n");
872     printf("T      - volume down\n");
873     printf("v      - volume up (via set absolute volume)\n");
874     printf("V      - volume down (via set absolute volume)\n");
875 
876     printf("---\n");
877 }
878 
879 static void stdin_process(char cmd){
880     uint8_t status = ERROR_CODE_SUCCESS;
881     switch (cmd){
882         case 'b':
883             status = a2dp_source_establish_stream(device_addr, &media_tracker.a2dp_cid);
884             printf("%c - Create A2DP Source connection to addr %s, cid 0x%02x.\n", cmd, bd_addr_to_str(device_addr), media_tracker.a2dp_cid);
885             break;
886         case 'B':
887             printf("%c - A2DP Source Disconnect from cid 0x%2x\n", cmd, media_tracker.a2dp_cid);
888             status = a2dp_source_disconnect(media_tracker.a2dp_cid);
889             break;
890         case 'c':
891             printf("%c - Create AVRCP connection to addr %s.\n", cmd, bd_addr_to_str(device_addr));
892             status = avrcp_connect(device_addr, &media_tracker.avrcp_cid);
893             break;
894         case 'C':
895             printf("%c - AVRCP disconnect\n", cmd);
896             status = avrcp_disconnect(media_tracker.avrcp_cid);
897             break;
898         case 'D':
899             printf("Deleting all link keys\n");
900             gap_delete_all_link_keys();
901             break;
902         case '\n':
903         case '\r':
904             break;
905 
906         case 't':
907             printf(" - volume up\n");
908             status = avrcp_controller_volume_up(media_tracker.avrcp_cid);
909             break;
910         case 'T':
911             printf(" - volume down\n");
912             status = avrcp_controller_volume_down(media_tracker.avrcp_cid);
913             break;
914 
915         case 'v':
916             if (media_tracker.volume > 117){
917                 media_tracker.volume = 127;
918             } else {
919                 media_tracker.volume += 10;
920             }
921             printf(" - volume up (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
922             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
923             break;
924         case 'V':
925             if (media_tracker.volume < 10){
926                 media_tracker.volume = 0;
927             } else {
928                 media_tracker.volume -= 10;
929             }
930             printf(" - volume down (via set absolute volume) %d%% (%d)\n",  media_tracker.volume * 100 / 127,  media_tracker.volume);
931             status = avrcp_controller_set_absolute_volume(media_tracker.avrcp_cid, media_tracker.volume);
932             break;
933 
934         case 'x':
935             if (media_tracker.avrcp_cid){
936                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
937             }
938             printf("%c - Play sine.\n", cmd);
939             data_source = STREAM_SINE;
940             if (!media_tracker.stream_opened) break;
941             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
942             break;
943         case 'z':
944             if (media_tracker.avrcp_cid){
945                 avrcp_target_set_now_playing_info(media_tracker.avrcp_cid, &tracks[data_source], sizeof(tracks)/sizeof(avrcp_track_t));
946             }
947             printf("%c - Play mod.\n", cmd);
948             data_source = STREAM_MOD;
949             if (!media_tracker.stream_opened) break;
950             status = a2dp_source_start_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
951             break;
952 
953         case 'p':
954             if (!media_tracker.stream_opened) break;
955             printf("%c - Pause stream.\n", cmd);
956             status = a2dp_source_pause_stream(media_tracker.a2dp_cid, media_tracker.local_seid);
957             break;
958 
959         case 'w':
960             if (!media_tracker.stream_opened) break;
961             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
962                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
963                 break;
964             }
965             new_sample_rate = 44100;
966             if (current_sample_rate == new_sample_rate){
967                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
968             } else {
969                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
970                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
971             }
972             break;
973 
974         case 'e':
975             if (!media_tracker.stream_opened) break;
976             if (play_info.status == AVRCP_PLAYBACK_STATUS_PLAYING){
977                 printf("Stream cannot be reconfigured while playing, please pause stream first\n");
978                 break;
979             }
980             new_sample_rate = 48000;
981             if (current_sample_rate == new_sample_rate){
982                 printf("%c - Stream already configured for %d Hz.\n", cmd, new_sample_rate);
983             } else {
984                 printf("%c - Reconfigure for %d Hz.\n", cmd, new_sample_rate);
985                 status = a2dp_source_reconfigure_stream_sampling_frequency(media_tracker.a2dp_cid, new_sample_rate);
986             }
987             break;
988 
989         default:
990             show_usage();
991             return;
992     }
993     if (status != ERROR_CODE_SUCCESS){
994         printf("Could not perform command \'%c\', status 0x%02x\n", cmd, status);
995     }
996 }
997 #endif
998 
999 
1000 int btstack_main(int argc, const char * argv[]);
1001 int btstack_main(int argc, const char * argv[]){
1002     (void)argc;
1003     (void)argv;
1004 
1005     int err = a2dp_source_and_avrcp_services_init();
1006     if (err) return err;
1007     // turn on!
1008     hci_power_control(HCI_POWER_ON);
1009     return 0;
1010 }
1011 /* EXAMPLE_END */
1012