ESP32 の BLEデバイス化にチャレンジ！（１）

ESP32 をスマホからBLEデバイスにするために試行錯誤をしています。コードを解析すればうまくいくかなと思ったのですが、なかなかうまくいかない。





BLEデバイスの中でも一番簡単なTHERMOMETER デバイスなら簡単にいくだろうと思い、 スケッチ化してみることにしました。参考にしたサイトはこちら。


Development of ESP-WROOM-32
https://github.com/mitazet/esp/blob/master/thermometer/main/gatts_thermometer.c


改造した Arduino のスケッチ？（ほぼCのプログラムですが）がこちらです。デバッグコードが入っていて、少し見苦しいですが我慢ください。

#pragma GCC diagnostic push
#pragma GCC diagnostic warning "-fpermissive"

#include 
#include 
#include 
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "bt.h"
#include "bta_api.h"

#include "esp_gap_ble_api.h"
#include "esp_gatts_api.h"
#include "esp_bt_defs.h"
#include "esp_bt_main.h"
#include "esp_bt_main.h"

#include "sdkconfig.h"

#define GATTS_TAG "GATTS_THERMO"

static void gatts_profile_thermo_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);

#define GATTS_SERVICE_UUID_THERMOMETER 0x00FF
#define GATTS_CHAR_UUID_THERMOMETER 0xFF01

#define GATTS_DESCR_UUID_THERMOMETER 0x3333
#define GATTS_NUM_HANDLE_THERMOMETER 4

#define TEST_DEVICE_NAME "ESP_THERMOMETER"


#define GATTS_DEMO_CHAR_VAL_LEN_MAX 0x40

#define PREPARE_BUF_MAX_SIZE 1024

#define PROFILE_NUM 1
#define PROFILE_THERMOMETER_ID 0

uint8_t char1_str[] = {0x11,0x22,0x33};
esp_attr_value_t gatts_demo_char1_val =
{
    .attr_max_len = GATTS_DEMO_CHAR_VAL_LEN_MAX,
    .attr_len = sizeof(char1_str),
    .attr_value = char1_str,
};

static uint8_t service_uuid128[32] = {
    /* LSB <--------------------------------------------------------------------------------> MSB */
    //first uuid, 16bit, [12],[13] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xAB, 0xCD, 0x00, 0x00,
    //second uuid, 32bit, [12], [13], [14], [15] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xAB, 0xCD, 0xAB, 0xCD,
};

static esp_ble_adv_data_t test_adv_data = {
    .set_scan_rsp = false,
    .include_name = true,
    .include_txpower = true,
    .min_interval = 0x20,
    .max_interval = 0x40,
    .appearance = 0x00,
    .manufacturer_len = 0,
    .p_manufacturer_data = NULL,
    .service_data_len = 0,
    .p_service_data = NULL,
    .service_uuid_len = 32,
    .p_service_uuid = service_uuid128,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

static esp_ble_adv_params_t test_adv_params;

struct gatts_profile_inst {
    esp_gatts_cb_t gatts_cb;
    uint16_t gatts_if;
    uint16_t app_id;
    uint16_t conn_id;
    uint16_t service_handle;
    esp_gatt_srvc_id_t service_id;
    esp_bt_uuid_t char_uuid;
    esp_bt_uuid_t descr_uuid;
    uint16_t char_handle;
    esp_gatt_perm_t perm;
    esp_gatt_char_prop_t property;
    uint16_t descr_handle;
};

static struct gatts_profile_inst test_profile;

typedef struct {
    uint8_t *prepare_buf;
    int prepare_len;
} prepare_type_env_t;

static prepare_type_env_t a_prepare_write_env;

void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);
void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);

static void gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
    Serial.println("gap_event_handler");

    switch (event) {
    case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
        Serial.println("ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT");
        esp_ble_gap_start_advertising(&test_adv_params);
        break;
        
    case ESP_GAP_BLE_ADV_DATA_RAW_SET_COMPLETE_EVT:
        Serial.println("ESP_GAP_BLE_ADV_DATA_RAW_SET_COMPLETE_EVT");
        esp_ble_gap_start_advertising(&test_adv_params);
        break;
        
    case ESP_GAP_BLE_SCAN_RSP_DATA_RAW_SET_COMPLETE_EVT:
        Serial.println("ESP_GAP_BLE_SCAN_RSP_DATA_RAW_SET_COMPLETE_EVT");
        esp_ble_gap_start_advertising(&test_adv_params);
        break;
        
    case ESP_GAP_BLE_ADV_START_COMPLETE_EVT:
        Serial.println("ESP_GAP_BLE_ADV_START_COMPLETE_EVT");
        if (param->adv_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
            Serial.println("Advertising start failed\n");
        }
        break;
    case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
        Serial.println("ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT");
        if (param->adv_stop_cmpl.status != ESP_BT_STATUS_SUCCESS) {
            Serial.println("Advertising stop failed\n");
        }
        else {
            Serial.println("Stop adv successfully\n");
        }
        break;
    case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT:
        Serial.println("ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT");
        break;
    default:
        break;
    }
}

void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){
    
    Serial.println("example_write_event_env");
    
    esp_gatt_status_t status = ESP_GATT_OK;

    if (param->write.need_rsp){
        if (param->write.is_prep){
            if (prepare_write_env->prepare_buf == NULL) {
                prepare_write_env->prepare_buf = (uint8_t*)malloc(PREPARE_BUF_MAX_SIZE*sizeof(uint8_t));
                prepare_write_env->prepare_len = 0;
            } else {
                if(param->write.offset > PREPARE_BUF_MAX_SIZE) {
                    status = ESP_GATT_INVALID_OFFSET;
                } else if ((param->write.offset + param->write.len) > PREPARE_BUF_MAX_SIZE) {
                    status = ESP_GATT_INVALID_ATTR_LEN;
                }
            }
            esp_gatt_rsp_t *gatt_rsp = (esp_gatt_rsp_t*)malloc(sizeof(esp_gatt_rsp_t));
            gatt_rsp->attr_value.len = param->write.len;
            gatt_rsp->attr_value.handle = param->write.handle;
            gatt_rsp->attr_value.offset = param->write.offset;
            gatt_rsp->attr_value.auth_req = ESP_GATT_AUTH_REQ_NONE;
            memcpy(gatt_rsp->attr_value.value, param->write.value, param->write.len);
            esp_err_t response_err = esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, gatt_rsp);
            free(gatt_rsp);
            if (status != ESP_GATT_OK) {
                return;
            }
            memcpy(prepare_write_env->prepare_buf + param->write.offset, param->write.value, param->write.len);
            prepare_write_env->prepare_len += param->write.len;
        }else{
            esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, NULL);
        }
    }
}

void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){ 
    
    Serial.println("example_exec_write_event_env");
    
    if (param->exec_write.exec_write_flag == ESP_GATT_PREP_WRITE_EXEC){
        esp_log_buffer_hex(GATTS_TAG, prepare_write_env->prepare_buf, prepare_write_env->prepare_len);
    }
    
    if (prepare_write_env->prepare_buf) {
        free(prepare_write_env->prepare_buf);
        prepare_write_env->prepare_buf = NULL;
    }
    
    prepare_write_env->prepare_len = 0;
}

static void gatts_profile_thermo_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param) {
  
    switch (event) {
    case ESP_GATTS_REG_EVT:
        Serial.println("ESP_GATTS_REG_EVT");    
        test_profile.service_id.is_primary = true;
        test_profile.service_id.id.inst_id = 0x00;
        test_profile.service_id.id.uuid.len = ESP_UUID_LEN_16;
        test_profile.service_id.id.uuid.uuid.uuid16 = GATTS_SERVICE_UUID_THERMOMETER;
        esp_ble_gap_set_device_name(TEST_DEVICE_NAME);
        esp_ble_gap_config_adv_data(&test_adv_data);
        esp_ble_gatts_create_service(gatts_if, &test_profile.service_id, GATTS_NUM_HANDLE_THERMOMETER);
        break;
        
    case ESP_GATTS_READ_EVT: {
        Serial.println("ESP_GATTS_READ_EVT");
        char temp1 = 0x1E; // dummy data
        char temp2 = 0x00; // dummy data
        esp_gatt_rsp_t rsp;
        memset(&rsp, 0, sizeof(esp_gatt_rsp_t));
        rsp.attr_value.handle = param->read.handle;
        rsp.attr_value.len = 2;
        rsp.attr_value.value[0] = temp1;
        rsp.attr_value.value[1] = temp2;
        esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id, ESP_GATT_OK, &rsp);
        break;
    }
    case ESP_GATTS_WRITE_EVT: {
        Serial.println("ESP_GATTS_WRITE_EVT");
        example_write_event_env(gatts_if, &a_prepare_write_env, param);
        break;
    }
    case ESP_GATTS_EXEC_WRITE_EVT:
        Serial.println("ESP_GATTS_EXEC_EVT");
        esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, ESP_GATT_OK, NULL);
        example_exec_write_event_env(&a_prepare_write_env, param);
        break;
        
    case ESP_GATTS_MTU_EVT:
        Serial.println("ESP_GATTS_MTU_EVT");
        break;
        
    case ESP_GATTS_CONF_EVT:
        Serial.println("ESP_GATTS_CONF_EVT");
        break;
        
    case ESP_GATTS_UNREG_EVT:
        Serial.println("ESP_GATTS_UNREG_EVT");
        break;
        
    case ESP_GATTS_CREATE_EVT:
        Serial.println("ESP_GATTS_CREATE_EVT");
        test_profile.service_handle = param->create.service_handle;
        test_profile.char_uuid.len = ESP_UUID_LEN_16;
        test_profile.char_uuid.uuid.uuid16 = GATTS_CHAR_UUID_THERMOMETER;
        
        esp_ble_gatts_start_service(test_profile.service_handle);
        esp_ble_gatts_add_char(test_profile.service_handle, &test_profile.char_uuid, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE, ESP_GATT_CHAR_PROP_BIT_READ | ESP_GATT_CHAR_PROP_BIT_WRITE | ESP_GATT_CHAR_PROP_BIT_NOTIFY, &gatts_demo_char1_val, NULL);
        break;
        
    case ESP_GATTS_ADD_INCL_SRVC_EVT:
        Serial.println("ESP_GATTS_ADD_INCL_SRVC_EVT");
        break;

    case ESP_GATTS_ADD_CHAR_EVT: {
        uint16_t length = 0;
        const uint8_t *prf_char;
        
        Serial.println("ESP_GATTS_ADD_CHAR_EVT");
        
        test_profile.char_handle = param->add_char.attr_handle;
        test_profile.descr_uuid.len = ESP_UUID_LEN_16;
        test_profile.descr_uuid.uuid.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG;
        
        esp_ble_gatts_get_attr_value(param->add_char.attr_handle, &length, &prf_char);
        esp_ble_gatts_add_char_descr(test_profile.service_handle, &test_profile.descr_uuid, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE, NULL, NULL);
        break;
    }

    case ESP_GATTS_ADD_CHAR_DESCR_EVT:
        Serial.println("ESP_GATTS_ADD_CHAR_DESCR_EVT");
        break;
        
    case ESP_GATTS_DELETE_EVT:
        Serial.println("ESP_GATTS_DELETE_EVT");
        break;
        
    case ESP_GATTS_START_EVT:
        Serial.println("ESP_GATTS_START_EVT");
        break;
        
    case ESP_GATTS_STOP_EVT:
        Serial.println("ESP_GATTS_STOP_EVT");
        break;
        
    case ESP_GATTS_CONNECT_EVT: {
        Serial.println("ESP_GATTS_CONNECT_EVT");
        
        esp_ble_conn_update_params_t conn_params = {0};
        memcpy(conn_params.bda, param->connect.remote_bda, sizeof(esp_bd_addr_t));
        
        /* For the IOS system, please reference the apple official documents about the ble connection parameters restrictions. */
        conn_params.latency = 0;
        conn_params.max_int = 0x50; // max_int = 0x50*1.25ms = 100ms
        conn_params.min_int = 0x30; // min_int = 0x30*1.25ms = 60ms
        conn_params.timeout =  400; // timeout = 400*10ms = 4000ms
        test_profile.conn_id = param->connect.conn_id;
        
        //start sent the update connection parameters to the peer device.
        esp_ble_gap_update_conn_params(&conn_params);
        break;
    }
    case ESP_GATTS_DISCONNECT_EVT:
        Serial.println("ESP_GATTS_DISCONNECT_EVT");
        esp_ble_gap_start_advertising(&test_adv_params);
        break;
        
    case ESP_GATTS_OPEN_EVT:
        Serial.println("ESP_GATTS_OPEN_EVT");
        break;

    case ESP_GATTS_CANCEL_OPEN_EVT:
        Serial.println("ESP_GATTS_CANCEL_OPEN_EVT");
        break;

    case ESP_GATTS_CLOSE_EVT:
        Serial.println("ESP_GATTS_CLOSE_EVT");
        break;

    case ESP_GATTS_LISTEN_EVT:
        Serial.println("ESP_GATTS_LISTEN_EVT");
        break;

    case ESP_GATTS_CONGEST_EVT:
        Serial.println("ESP_GATTS_CONGEST_EVT");
        break;

    default:
        break;
    }
}

static void gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param)
{
    Serial.println("gatts_event_handler");

    /* If event is register event, store the gatts_if for each profile */
    if (event == ESP_GATTS_REG_EVT) {
        if (param->reg.status == ESP_GATT_OK) {
            test_profile.gatts_if = gatts_if;
        } else {
            return;
        }
    }

    if (gatts_if == ESP_GATT_IF_NONE || gatts_if == test_profile.gatts_if) {
        if (test_profile.gatts_cb) {
            test_profile.gatts_cb(event, gatts_if, param);
        }
    }
}

void setup() {

    Serial.begin(115200);

    /* initialize advertising info */
    test_adv_params.adv_int_min       = 0x20;
    test_adv_params.adv_int_max      = 0x40;
    test_adv_params.adv_type            = ADV_TYPE_IND;
    test_adv_params.own_addr_type  = BLE_ADDR_TYPE_PUBLIC;
    test_adv_params.channel_map     = ADV_CHNL_ALL;
    test_adv_params.adv_filter_policy = ADV_FILTER_ALLOW_SCAN_ANY_CON_ANY;

    /* initialize profile and characteristic */
    test_profile.gatts_cb = gatts_profile_thermo_event_handler;
    test_profile.gatts_if = ESP_GATT_IF_NONE; 

    esp_err_t ret;
    
    btStart();
    ret = esp_bluedroid_init();
    if (ret) {
        Serial.println("Init bluetooth failed");
        return;
    }
    ret = esp_bluedroid_enable();
    if (ret) {
        Serial.println("Enable bluetooth failed");
        return;
    }

    esp_ble_gatts_register_callback(gatts_event_handler);
    esp_ble_gap_register_callback(gap_event_handler);
    esp_ble_gatts_app_register(PROFILE_THERMOMETER_ID);

    Serial.println("Bluetooth setup success!");
}

void loop() {
}

LAPIS Computer から出しているスマホアプリの BLE Tools を起動してみると、ESP32_THERMOMETER が見えました！





しかし、値は取れず…残念。





シリアルモニターを確認すると、CONNECTまでは成功していますが、その後にREADのイベントが発生していません。

Bluetooth setup success!
gatts_event_handler
ESP_GATTS_REG_EVT
gap_event_handler
ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT
gatts_event_handler
ESP_GATTS_CREATE_EVT
gap_event_handler
ESP_GAP_BLE_ADV_START_COMPLETE_EVT
gatts_event_handler
ESP_GATTS_START_EVT
gatts_event_handler
ESP_GATTS_ADD_CHAR_EVT
gatts_event_handler
ESP_GATTS_ADD_CHAR_DESCR_EVT
gatts_event_handler
ESP_GATTS_CONNECT_EVT
gap_event_handler
ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT
gatts_event_handler

うーん、何が原因なのか。そもそもシーケンスが間違っているのか。。。もう少し追いかけてみたいところですが、最近は忙しくて時間がとれないんだよなぁ。
(;´д｀)トホホ

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MicroPython for ESP32 Development Workshop (English Edition)

• 出版社/メーカー:
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