gistfile1.txt

// this is a hack of:
// https://github.com/gtalusan/esp-idf/blob/master/examples/bluetooth/a2dp_source/main/main.c
// the idea is to be able to play an audio file from an esp32's flash memory directly to a bluetooth audio speaker
// refer to here for the notes on what you need to do to pull it all together


/*
   This example code is in the Public Domain (or CC0 licensed, at your option.)

   Unless required by applicable law or agreed to in writing, this
   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
   CONDITIONS OF ANY KIND, either express or implied.
*/

#include "sbc_data.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/unistd.h>
#include <unistd.h>

#include "bt_app_core.h"
#include "esp_a2dp_api.h"
#include "esp_avrc_api.h"
#include "esp_bt.h"
#include "esp_bt_device.h"
#include "esp_bt_main.h"
#include "esp_err.h"
#include "esp_gap_bt_api.h"
#include "esp_log.h"
#include "esp_partition.h"
#include "esp_spiffs.h"
#include "esp_system.h"
#include "esp_vfs.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/timers.h"
#include "nvs.h"
#include "nvs_flash.h"


#define BT_AV_TAG               "BT_AV"


/* event for handler "bt_av_hdl_stack_up */
enum {
    BT_APP_EVT_STACK_UP = 0,
};

/* A2DP global state */
enum {
    APP_AV_STATE_IDLE,
    APP_AV_STATE_DISCOVERING,
    APP_AV_STATE_DISCOVERED,
    APP_AV_STATE_UNCONNECTED,
    APP_AV_STATE_CONNECTING,
    APP_AV_STATE_CONNECTED,
    APP_AV_STATE_DISCONNECTING,
};

/* sub states of APP_AV_STATE_CONNECTED */
enum {
    APP_AV_MEDIA_STATE_IDLE,
    APP_AV_MEDIA_STATE_STARTING,
    APP_AV_MEDIA_STATE_STARTED,
    APP_AV_MEDIA_STATE_STOPPING,
};

#define BT_APP_HEART_BEAT_EVT                (0xff00)
static const char *TAG = "example";

/// handler for bluetooth stack enabled events
static void bt_av_hdl_stack_evt(uint16_t event, void *p_param);

/// callback function for A2DP source
static void bt_app_a2d_cb(esp_a2d_cb_event_t event, esp_a2d_cb_param_t *param);

/// callback function for A2DP source audio data stream
static int32_t bt_app_a2d_data_cb(uint8_t *data, int32_t len);

static void a2d_app_heart_beat(void *arg);

/// A2DP application state machine
static void bt_app_av_sm_hdlr(uint16_t event, void *param);

/* A2DP application state machine handler for each state */
static void bt_app_av_state_unconnected(uint16_t event, void *param);
static void bt_app_av_state_connecting(uint16_t event, void *param);
static void bt_app_av_state_connected(uint16_t event, void *param);
static void bt_app_av_state_disconnecting(uint16_t event, void *param);

static esp_bd_addr_t s_peer_bda = {0};
static uint8_t s_peer_bdname[ESP_BT_GAP_MAX_BDNAME_LEN + 1];
static int s_a2d_state = APP_AV_STATE_IDLE;
static int s_media_state = APP_AV_MEDIA_STATE_IDLE;
static int s_intv_cnt = 0;
static int s_connecting_intv = 0;
static uint32_t s_pkt_cnt = 0;

static TimerHandle_t s_tmr;

static char *bda2str(esp_bd_addr_t bda, char *str, size_t size)
{
    if (bda == NULL || str == NULL || size < 18) {
        return NULL;
    }

    uint8_t *p = bda;
    sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
            p[0], p[1], p[2], p[3], p[4], p[5]);
    return str;
}

FILE* sample_file;

void test_spiffs_create_file_with_text(const char* name, const char* text)
{
    FILE* f = fopen(name, "wb");
    fputs(text, f);
    fclose(f);
}

void list_directory(const char* path)
{
    printf("list_directory\n");
    DIR* dir = opendir(path);
    while (true) {
        struct dirent* de = readdir(dir);
        if (!de) {
            break;
        }
        printf("file found: %s\n", de->d_name);
        char pathname[1024];   /* should alwys be big enough */
        sprintf( pathname, "%s/%s", "/spiffs", de->d_name );
        printf("pathname: %s\n", pathname);
        FILE* f = fopen(pathname, "r");
        if (f == NULL) {
            printf("could not open: %s\n", de->d_name);
        } else {
            printf("could open: %s\n", de->d_name);
            //char buf[32] = { 0 };
            //int cb = fread(buf, 1, sizeof(buf), f);
            fclose(f);
        };
    }
    closedir(dir);
}


void listPartitions(void)
{
    printf("listPartitions\n");
    size_t ul;
    esp_partition_iterator_t _mypartiterator;
    const esp_partition_t *_mypart;
    ul = spi_flash_get_chip_size();
    printf("Flash chip size: %u\n", ul);

    //Serial.print("Flash chip size: ");
    //Serial.println(ul);
    printf("Partiton table: \n");
    _mypartiterator = esp_partition_find(ESP_PARTITION_TYPE_APP, ESP_PARTITION_SUBTYPE_ANY, NULL);
    if (_mypartiterator)
    {
        do
        {
            _mypart = esp_partition_get(_mypartiterator);
            printf("%x - %x - %x - %x - %s - %i\r\n", _mypart->type, _mypart->subtype, _mypart->address, _mypart->size, _mypart->label, _mypart->encrypted);
        } while ((_mypartiterator = esp_partition_next(_mypartiterator)));
    }
    esp_partition_iterator_release(_mypartiterator);
    _mypartiterator = esp_partition_find(ESP_PARTITION_TYPE_DATA, ESP_PARTITION_SUBTYPE_ANY, NULL);
    if (_mypartiterator)
    {
        do
        {
            _mypart = esp_partition_get(_mypartiterator);
            printf("%x - %x - %x - %x - %s - %i\r\n", _mypart->type, _mypart->subtype, _mypart->address, _mypart->size, _mypart->label, _mypart->encrypted);
        } while ((_mypartiterator = esp_partition_next(_mypartiterator)));
    }
    esp_partition_iterator_release(_mypartiterator);
}


void init_spiffs()
{
    ESP_LOGI(TAG, "Initializing SPIFFS");

    esp_vfs_spiffs_conf_t conf = {
      .base_path = "/spiffs",
      .partition_label = NULL,
      .max_files = 5,
      .format_if_mount_failed = false
    };

    // Use settings defined above to initialize and mount SPIFFS filesystem.
    // Note: esp_vfs_spiffs_register is an all-in-one convenience function.
    esp_err_t ret = esp_vfs_spiffs_register(&conf);

    // Use POSIX and C standard library functions to work with files.
    // First create a file.
    ESP_LOGI(TAG, "Opening file");
    FILE* f = fopen("/spiffs/hello.txt", "w");
    if (f == NULL) {
        ESP_LOGE(TAG, "Failed to open file for writing");
        return;
    }
    fprintf(f, "Hello World!\n");
    fclose(f);
    ESP_LOGI(TAG, "File written");


    if (ret != ESP_OK) {
        if (ret == ESP_FAIL) {
            ESP_LOGE(TAG, "Failed to mount or format filesystem");
        } else if (ret == ESP_ERR_NOT_FOUND) {
            ESP_LOGE(TAG, "Failed to find SPIFFS partition");
        } else {
            ESP_LOGE(TAG, "Failed to initialize SPIFFS (%s)", esp_err_to_name(ret));
        }
        return;
    }


    size_t total = 0, used = 0;
    ret = esp_spiffs_info(NULL, &total, &used);
    if (ret != ESP_OK) {
        ESP_LOGE(TAG, "Failed to get SPIFFS partition information (%s)", esp_err_to_name(ret));
    } else {
        ESP_LOGI(TAG, "Partition size: total: %d, used: %d", total, used);
    }


}




void app_main()
{
    init_spiffs();

    ESP_LOGE(TAG, "list files in /spiffs");
    list_directory("/spiffs");

    struct stat st;
    if (stat("/spiffs/pcm2444s.wav", &st) == 0) {
        ESP_LOGI(TAG, "/spiffs/pcm2444s.wav found");
       sample_file = fopen("/spiffs/pcm2444s.wav", "rb");

    } else {
        ESP_LOGI(TAG, "/spiffs/pcm2444s.wav not found");
    }



    // Initialize NVS.
    esp_err_t ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        ESP_ERROR_CHECK(nvs_flash_erase());
        ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK( ret );

    ESP_ERROR_CHECK(esp_bt_controller_mem_release(ESP_BT_MODE_BLE));

    esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();

    if (esp_bt_controller_init(&bt_cfg) != ESP_OK) {
        ESP_LOGE(BT_AV_TAG, "%s initialize controller failed\n", __func__);
        return;
    }

    if (esp_bt_controller_enable(ESP_BT_MODE_CLASSIC_BT) != ESP_OK) {
        ESP_LOGE(BT_AV_TAG, "%s enable controller failed\n", __func__);
        return;
    }

    if (esp_bluedroid_init() != ESP_OK) {
        ESP_LOGE(BT_AV_TAG, "%s initialize bluedroid failed\n", __func__);
        return;
    }

    if (esp_bluedroid_enable() != ESP_OK) {
        ESP_LOGE(BT_AV_TAG, "%s enable bluedroid failed\n", __func__);
        return;
    }

    /* create application task */
    bt_app_task_start_up();

    /* Bluetooth device name, connection mode and profile set up */
    bt_app_work_dispatch(bt_av_hdl_stack_evt, BT_APP_EVT_STACK_UP, NULL, 0, NULL);

    /* Set default parameters for Secure Simple Pairing */
    esp_bt_sp_param_t param_type = ESP_BT_SP_IOCAP_MODE;
    esp_bt_io_cap_t iocap = ESP_BT_IO_CAP_IO;
    esp_bt_gap_set_security_param(param_type, &iocap, sizeof(uint8_t));

    /*
     * Set default parameters for Legacy Pairing
     * Use variable pin, input pin code when pairing
     */
    esp_bt_pin_type_t pin_type = ESP_BT_PIN_TYPE_VARIABLE;
    esp_bt_pin_code_t pin_code;
    esp_bt_gap_set_pin(pin_type, 0, pin_code);
}




static bool get_name_from_eir(uint8_t *eir, uint8_t *bdname, uint8_t *bdname_len)
{
    uint8_t *rmt_bdname = NULL;
    uint8_t rmt_bdname_len = 0;

    if (!eir) {
        return false;
    }

    rmt_bdname = esp_bt_gap_resolve_eir_data(eir, ESP_BT_EIR_TYPE_CMPL_LOCAL_NAME, &rmt_bdname_len);
    if (!rmt_bdname) {
        rmt_bdname = esp_bt_gap_resolve_eir_data(eir, ESP_BT_EIR_TYPE_SHORT_LOCAL_NAME, &rmt_bdname_len);
    }

    if (rmt_bdname) {
        if (rmt_bdname_len > ESP_BT_GAP_MAX_BDNAME_LEN) {
            rmt_bdname_len = ESP_BT_GAP_MAX_BDNAME_LEN;
        }

        if (bdname) {
            memcpy(bdname, rmt_bdname, rmt_bdname_len);
            bdname[rmt_bdname_len] = '\0';
        }
        if (bdname_len) {
            *bdname_len = rmt_bdname_len;
        }
        return true;
    }

    return false;
}

static void filter_inquiry_scan_result(esp_bt_gap_cb_param_t *param)
{
    char bda_str[18];
    uint32_t cod = 0;
    int32_t rssi = -129; /* invalid value */
    uint8_t *eir = NULL;
    esp_bt_gap_dev_prop_t *p;

    ESP_LOGI(BT_AV_TAG, "Scanned device: %s", bda2str(param->disc_res.bda, bda_str, 18));
    ESP_LOGI(BT_AV_TAG, "Found device, address %s, name %s", bda_str, s_peer_bdname);
    for (int i = 0; i < param->disc_res.num_prop; i++) {
        p = param->disc_res.prop + i;
        switch (p->type) {
        case ESP_BT_GAP_DEV_PROP_COD:
            cod = *(uint32_t *)(p->val);
            ESP_LOGI(BT_AV_TAG, "--Class of Device: 0x%x", cod);
            break;
        case ESP_BT_GAP_DEV_PROP_RSSI:
            rssi = *(int8_t *)(p->val);
            ESP_LOGI(BT_AV_TAG, "--RSSI: %d", rssi);
            break;
        case ESP_BT_GAP_DEV_PROP_EIR:
            eir = (uint8_t *)(p->val);
            break;
        case ESP_BT_GAP_DEV_PROP_BDNAME:
        default:
            break;
        }
    }

    if (eir) {
        get_name_from_eir(eir, s_peer_bdname, NULL);
        ESP_LOGI(BT_AV_TAG, "Found device, address %s, name %s", bda_str, s_peer_bdname);
    }


    /* search for device with MAJOR service class as "rendering" in COD */
    if (!esp_bt_gap_is_valid_cod(cod) ||
            !(esp_bt_gap_get_cod_srvc(cod) & ESP_BT_COD_SRVC_RENDERING)) {
        return;
    }

    /* search for device named "ESP_SPEAKER" in its extended inqury response */
    if (eir) {
        get_name_from_eir(eir, s_peer_bdname, NULL);
        //if (strcmp((char *)s_peer_bdname, "ESP_SPEAKER") != 0) {
        ESP_LOGI(BT_AV_TAG, "Found device, address %s, name %s", bda_str, s_peer_bdname);
        if (strcmp((char *)s_peer_bdname, "30070915") != 0) {
            return;
        }

        ESP_LOGI(BT_AV_TAG, "Found a target device, address %s, name %s", bda_str, s_peer_bdname);
        s_a2d_state = APP_AV_STATE_DISCOVERED;
        memcpy(s_peer_bda, param->disc_res.bda, ESP_BD_ADDR_LEN);
        ESP_LOGI(BT_AV_TAG, "Cancel device discovery ...");
        esp_bt_gap_cancel_discovery();
    }
}


void bt_app_gap_cb(esp_bt_gap_cb_event_t event, esp_bt_gap_cb_param_t *param)
{
    switch (event) {
    case ESP_BT_GAP_DISC_RES_EVT: {
        filter_inquiry_scan_result(param);
        break;
    }
    case ESP_BT_GAP_DISC_STATE_CHANGED_EVT: {
        if (param->disc_st_chg.state == ESP_BT_GAP_DISCOVERY_STOPPED) {
            if (s_a2d_state == APP_AV_STATE_DISCOVERED) {
                s_a2d_state = APP_AV_STATE_CONNECTING;
                ESP_LOGI(BT_AV_TAG, "Device discovery stopped.");
                ESP_LOGI(BT_AV_TAG, "a2dp connecting to peer: %s", s_peer_bdname);
                esp_a2d_source_connect(s_peer_bda);
            } else {
                // not discovered, continue to discover
                ESP_LOGI(BT_AV_TAG, "Device discovery failed, continue to discover...");
                esp_bt_gap_start_discovery(ESP_BT_INQ_MODE_GENERAL_INQUIRY, 10, 0);
            }
        } else if (param->disc_st_chg.state == ESP_BT_GAP_DISCOVERY_STARTED) {
            ESP_LOGI(BT_AV_TAG, "Discovery started.");
        }
        break;
    }
    case ESP_BT_GAP_RMT_SRVCS_EVT:
    case ESP_BT_GAP_RMT_SRVC_REC_EVT:
        break;
    case ESP_BT_GAP_AUTH_CMPL_EVT: {
        if (param->auth_cmpl.stat == ESP_BT_STATUS_SUCCESS) {
            ESP_LOGI(BT_AV_TAG, "authentication success: %s", param->auth_cmpl.device_name);
            esp_log_buffer_hex(BT_AV_TAG, param->auth_cmpl.bda, ESP_BD_ADDR_LEN);
        } else {
            ESP_LOGE(BT_AV_TAG, "authentication failed, status:%d", param->auth_cmpl.stat);
        }
        break;
    }
    case ESP_BT_GAP_PIN_REQ_EVT: {
        ESP_LOGI(BT_AV_TAG, "ESP_BT_GAP_PIN_REQ_EVT min_16_digit:%d", param->pin_req.min_16_digit);
        if (param->pin_req.min_16_digit) {
            ESP_LOGI(BT_AV_TAG, "Input pin code: 0000 0000 0000 0000");
            esp_bt_pin_code_t pin_code = {0};
            esp_bt_gap_pin_reply(param->pin_req.bda, true, 16, pin_code);
        } else {
            ESP_LOGI(BT_AV_TAG, "Input pin code: 1234");
            esp_bt_pin_code_t pin_code;
            pin_code[0] = '1';
            pin_code[1] = '2';
            pin_code[2] = '3';
            pin_code[3] = '4';
            esp_bt_gap_pin_reply(param->pin_req.bda, true, 4, pin_code);
        }
        break;
    }
    case ESP_BT_GAP_CFM_REQ_EVT:
        ESP_LOGI(BT_AV_TAG, "ESP_BT_GAP_CFM_REQ_EVT Please compare the numeric value: %d", param->cfm_req.num_val);
        esp_bt_gap_ssp_confirm_reply(param->cfm_req.bda, true);
        break;
    case ESP_BT_GAP_KEY_NOTIF_EVT:
        ESP_LOGI(BT_AV_TAG, "ESP_BT_GAP_KEY_NOTIF_EVT passkey:%d", param->key_notif.passkey);
        break;
    case ESP_BT_GAP_KEY_REQ_EVT:
        ESP_LOGI(BT_AV_TAG, "ESP_BT_GAP_KEY_REQ_EVT Please enter passkey!");
        break;
    default: {
        ESP_LOGI(BT_AV_TAG, "event: %d", event);
        break;
    }
    }
    return;
}

static void bt_av_hdl_stack_evt(uint16_t event, void *p_param)
{
    ESP_LOGD(BT_AV_TAG, "%s evt %d", __func__, event);
    switch (event) {
    case BT_APP_EVT_STACK_UP: {
        /* set up device name */
        char *dev_name = "ESP_A2DP_SRC";
        esp_bt_dev_set_device_name(dev_name);

        /* register GAP callback function */
        esp_bt_gap_register_callback(bt_app_gap_cb);

        /* initialize A2DP source */
        esp_a2d_register_callback(&bt_app_a2d_cb);
        esp_a2d_source_register_data_callback(bt_app_a2d_data_cb);
        esp_a2d_source_init();

        /* set discoverable and connectable mode */
        esp_bt_gap_set_scan_mode(ESP_BT_SCAN_MODE_CONNECTABLE_DISCOVERABLE);

        /* start device discovery */
        ESP_LOGI(BT_AV_TAG, "Starting device discovery...");
        s_a2d_state = APP_AV_STATE_DISCOVERING;
        esp_bt_gap_start_discovery(ESP_BT_INQ_MODE_GENERAL_INQUIRY, 10, 0);

        /* create and start heart beat timer */
        do {
            int tmr_id = 0;
            s_tmr = xTimerCreate("connTmr", (10000 / portTICK_RATE_MS),
                               pdTRUE, (void *)tmr_id, a2d_app_heart_beat);
            xTimerStart(s_tmr, portMAX_DELAY);
        } while (0);
        break;
    }
    default:
        ESP_LOGE(BT_AV_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

static void bt_app_a2d_cb(esp_a2d_cb_event_t event, esp_a2d_cb_param_t *param)
{
    bt_app_work_dispatch(bt_app_av_sm_hdlr, event, param, sizeof(esp_a2d_cb_param_t), NULL);
}

unsigned long long pos = 0;         //current position in the audio sample, using fixed point
unsigned int posLow = 0;

static int32_t bt_app_a2d_data_cb(uint8_t *data, int32_t len)
{
    //ESP_LOGE(BT_AV_TAG, "callback");

    if (len < 0 || data == NULL) {
        return 0;
    }

    if (sample_file == NULL) {
        ESP_LOGE(BT_AV_TAG, "callback says sample file is not open");
        return 0;
    }

    //ESP_LOGE(BT_AV_TAG, "callback");
    int l = fread(data, 1, len, sample_file);
    //ESP_LOGE(BT_AV_TAG, "read done %d", len);
/*
// log output as hex to see what's going on
int i;
for (i = 0; i < len; i++)
{
    if (i > 0) printf(":");
    printf("%02X", data[i]);
}
printf("\n");
*/
    if (l < len) {
        fseek(sample_file, 0, SEEK_SET);
    }
    return len;
}

static void a2d_app_heart_beat(void *arg)
{
    bt_app_work_dispatch(bt_app_av_sm_hdlr, BT_APP_HEART_BEAT_EVT, NULL, 0, NULL);
}

static void bt_app_av_sm_hdlr(uint16_t event, void *param)
{
    ESP_LOGI(BT_AV_TAG, "%s state %d, evt 0x%x", __func__, s_a2d_state, event);
    switch (s_a2d_state) {
    case APP_AV_STATE_DISCOVERING:
    case APP_AV_STATE_DISCOVERED:
        break;
    case APP_AV_STATE_UNCONNECTED:
        bt_app_av_state_unconnected(event, param);
        break;
    case APP_AV_STATE_CONNECTING:
        bt_app_av_state_connecting(event, param);
        break;
    case APP_AV_STATE_CONNECTED:
        bt_app_av_state_connected(event, param);
        break;
    case APP_AV_STATE_DISCONNECTING:
        bt_app_av_state_disconnecting(event, param);
        break;
    default:
        ESP_LOGE(BT_AV_TAG, "%s invalid state %d", __func__, s_a2d_state);
        break;
    }
}

static void bt_app_av_state_unconnected(uint16_t event, void *param)
{
    switch (event) {
    case ESP_A2D_CONNECTION_STATE_EVT:
    case ESP_A2D_AUDIO_STATE_EVT:
    case ESP_A2D_AUDIO_CFG_EVT:
    case ESP_A2D_MEDIA_CTRL_ACK_EVT:
        break;
    case BT_APP_HEART_BEAT_EVT: {
        uint8_t *p = s_peer_bda;
        //dude
        ESP_LOGI(BT_AV_TAG, "a2dp connecting to peer: %s", s_peer_bdname);
        //dude

        ESP_LOGI(BT_AV_TAG, "a2dp connecting to peer: %02x:%02x:%02x:%02x:%02x:%02x",
                 p[0], p[1], p[2], p[3], p[4], p[5]);
        esp_a2d_source_connect(s_peer_bda);
        s_a2d_state = APP_AV_STATE_CONNECTING;
        s_connecting_intv = 0;
        break;
    }
    default:
        ESP_LOGE(BT_AV_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

static void bt_app_av_state_connecting(uint16_t event, void *param)
{
    esp_a2d_cb_param_t *a2d = NULL;
    switch (event) {
    case ESP_A2D_CONNECTION_STATE_EVT: {
        a2d = (esp_a2d_cb_param_t *)(param);
        if (a2d->conn_stat.state == ESP_A2D_CONNECTION_STATE_CONNECTED) {
            ESP_LOGI(BT_AV_TAG, "a2dp connected");
            s_a2d_state =  APP_AV_STATE_CONNECTED;
            s_media_state = APP_AV_MEDIA_STATE_IDLE;
            esp_bt_gap_set_scan_mode(ESP_BT_SCAN_MODE_NONE);
        } else if (a2d->conn_stat.state == ESP_A2D_CONNECTION_STATE_DISCONNECTED) {
            s_a2d_state =  APP_AV_STATE_UNCONNECTED;
        }
        break;
    }
    case ESP_A2D_AUDIO_STATE_EVT:
    case ESP_A2D_AUDIO_CFG_EVT:
    case ESP_A2D_MEDIA_CTRL_ACK_EVT:
        break;
    case BT_APP_HEART_BEAT_EVT:
        if (++s_connecting_intv >= 2) {
            s_a2d_state = APP_AV_STATE_UNCONNECTED;
            s_connecting_intv = 0;
        }
        break;
    default:
        ESP_LOGE(BT_AV_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

static void bt_app_av_media_proc(uint16_t event, void *param)
{
    esp_a2d_cb_param_t *a2d = NULL;
    switch (s_media_state) {
    case APP_AV_MEDIA_STATE_IDLE: {
        if (event == BT_APP_HEART_BEAT_EVT) {
            ESP_LOGI(BT_AV_TAG, "a2dp media ready checking ...");
            esp_a2d_media_ctrl(ESP_A2D_MEDIA_CTRL_CHECK_SRC_RDY);
        } else if (event == ESP_A2D_MEDIA_CTRL_ACK_EVT) {
            a2d = (esp_a2d_cb_param_t *)(param);
            if (a2d->media_ctrl_stat.cmd == ESP_A2D_MEDIA_CTRL_CHECK_SRC_RDY &&
                    a2d->media_ctrl_stat.status == ESP_A2D_MEDIA_CTRL_ACK_SUCCESS) {
                ESP_LOGI(BT_AV_TAG, "a2dp media ready, starting ...");
                esp_a2d_media_ctrl(ESP_A2D_MEDIA_CTRL_START);
                s_media_state = APP_AV_MEDIA_STATE_STARTING;
            }
        }
        break;
    }
    case APP_AV_MEDIA_STATE_STARTING: {
        if (event == ESP_A2D_MEDIA_CTRL_ACK_EVT) {
            a2d = (esp_a2d_cb_param_t *)(param);
            if (a2d->media_ctrl_stat.cmd == ESP_A2D_MEDIA_CTRL_START &&
                    a2d->media_ctrl_stat.status == ESP_A2D_MEDIA_CTRL_ACK_SUCCESS) {
                ESP_LOGI(BT_AV_TAG, "a2dp media start successfully.");
                s_intv_cnt = 0;
                s_media_state = APP_AV_MEDIA_STATE_STARTED;
            } else {
                // not started succesfully, transfer to idle state
                ESP_LOGI(BT_AV_TAG, "a2dp media start failed.");
                s_media_state = APP_AV_MEDIA_STATE_IDLE;
            }
        }
        break;
    }
    case APP_AV_MEDIA_STATE_STARTED: {
        if (event == BT_APP_HEART_BEAT_EVT) {
            if (++s_intv_cnt >= 10) {
                ESP_LOGI(BT_AV_TAG, "a2dp media stopping...");
                esp_a2d_media_ctrl(ESP_A2D_MEDIA_CTRL_STOP);
                s_media_state = APP_AV_MEDIA_STATE_STOPPING;
                s_intv_cnt = 0;
            }
        }
        break;
    }
    case APP_AV_MEDIA_STATE_STOPPING: {
        if (event == ESP_A2D_MEDIA_CTRL_ACK_EVT) {
            a2d = (esp_a2d_cb_param_t *)(param);
            if (a2d->media_ctrl_stat.cmd == ESP_A2D_MEDIA_CTRL_STOP &&
                    a2d->media_ctrl_stat.status == ESP_A2D_MEDIA_CTRL_ACK_SUCCESS) {
                ESP_LOGI(BT_AV_TAG, "a2dp media stopped successfully, disconnecting...");
                s_media_state = APP_AV_MEDIA_STATE_IDLE;
                esp_a2d_source_disconnect(s_peer_bda);
                s_a2d_state = APP_AV_STATE_DISCONNECTING;
            } else {
                ESP_LOGI(BT_AV_TAG, "a2dp media stopping...");
                esp_a2d_media_ctrl(ESP_A2D_MEDIA_CTRL_STOP);
            }
        }
        break;
    }
    }
}

static void bt_app_av_state_connected(uint16_t event, void *param)
{
    esp_a2d_cb_param_t *a2d = NULL;
    switch (event) {
    case ESP_A2D_CONNECTION_STATE_EVT: {
        a2d = (esp_a2d_cb_param_t *)(param);
        if (a2d->conn_stat.state == ESP_A2D_CONNECTION_STATE_DISCONNECTED) {
            ESP_LOGI(BT_AV_TAG, "a2dp disconnected");
            s_a2d_state = APP_AV_STATE_UNCONNECTED;
            esp_bt_gap_set_scan_mode(ESP_BT_SCAN_MODE_CONNECTABLE_DISCOVERABLE);
        }
        break;
    }
    case ESP_A2D_AUDIO_STATE_EVT: {
        a2d = (esp_a2d_cb_param_t *)(param);
        if (ESP_A2D_AUDIO_STATE_STARTED == a2d->audio_stat.state) {
            s_pkt_cnt = 0;
        }
        break;
    }
    case ESP_A2D_AUDIO_CFG_EVT:
        // not suppposed to occur for A2DP source
        break;
    case ESP_A2D_MEDIA_CTRL_ACK_EVT:
    case BT_APP_HEART_BEAT_EVT: {
        bt_app_av_media_proc(event, param);
        break;
    }
    default:
        ESP_LOGE(BT_AV_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

static void bt_app_av_state_disconnecting(uint16_t event, void *param)
{
    esp_a2d_cb_param_t *a2d = NULL;
    switch (event) {
    case ESP_A2D_CONNECTION_STATE_EVT: {
        a2d = (esp_a2d_cb_param_t *)(param);
        if (a2d->conn_stat.state == ESP_A2D_CONNECTION_STATE_DISCONNECTED) {
            ESP_LOGI(BT_AV_TAG, "a2dp disconnected");
            s_a2d_state =  APP_AV_STATE_UNCONNECTED;
            esp_bt_gap_set_scan_mode(ESP_BT_SCAN_MODE_CONNECTABLE_DISCOVERABLE);
        }
        break;
    }
    case ESP_A2D_AUDIO_STATE_EVT:
    case ESP_A2D_AUDIO_CFG_EVT:
    case ESP_A2D_MEDIA_CTRL_ACK_EVT:
    case BT_APP_HEART_BEAT_EVT:
        break;
    default:
        ESP_LOGE(BT_AV_TAG, "%s unhandled evt %d", __func__, event);
        break;
    }
}

Hello Mister,

I loved ur code, can I make a few questions? how to store or upload the sbc file?