例程简介
此例程使用一种类似表的数据结构实现BLE GATT服务器，来定义服务器service和characteristic。此示例演示了一种在一个位置定义服务器功能的实用方法，而不是逐个添加service和characteristic
这里以定义在Traditional Profile Specifications中的心率profile为例
由于大部分代码与gatt_server几乎完全一致，因此，这里只对不同的地方进行说明
属性表
用于后面创建属性表，属性表包括service/characteritic/descriptor的相关设置。
属性表每一项包含以下：
esp_attr_control attr_control：属性控制位。成员包括uint8_t auto_rep- 当设置为
ESP_GATT_REP_BY_APP时，读写操作的响应由应用回复 - 当设置为
ESP_GATT_AUTO_RSP时，读写操作的响应由GATT栈自动回复
- 当设置为
esp_attr_desc_t att_desc：属性类型，成员包括以下几个uint16_t uuid_length：UUID长度uint8_t *uuid_p：UUID的值uint16_t perm：属性权限，包括是否能被读写等uint16_t max_length：元素的最大长度uint16_t length：元素当前的长度uint8_t *value：元素值数组
/* Full Database Description - Used to add attributes into the database */
static const esp_gatts_attr_db_t gatt_db[HRS_IDX_NB] =
{
// Service Declaration
[IDX_SVC] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&primary_service_uuid, ESP_GATT_PERM_READ,
sizeof(uint16_t), sizeof(GATTS_SERVICE_UUID_TEST), (uint8_t *)&GATTS_SERVICE_UUID_TEST}},
/* Characteristic Declaration 特征声明，对应特征的property*/
[IDX_CHAR_A] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&character_declaration_uuid, ESP_GATT_PERM_READ,
CHAR_DECLARATION_SIZE, CHAR_DECLARATION_SIZE, (uint8_t *)&char_prop_read_write_notify}},
/* Characteristic Value */
[IDX_CHAR_VAL_A] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&GATTS_CHAR_UUID_TEST_A, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
GATTS_DEMO_CHAR_VAL_LEN_MAX, sizeof(char_value), (uint8_t *)char_value}},
/* Client Characteristic Configuration Descriptor */
[IDX_CHAR_CFG_A] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&character_client_config_uuid, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
sizeof(uint16_t), sizeof(heart_measurement_ccc), (uint8_t *)heart_measurement_ccc}},
/* Characteristic Declaration */
[IDX_CHAR_B] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&character_declaration_uuid, ESP_GATT_PERM_READ,
CHAR_DECLARATION_SIZE, CHAR_DECLARATION_SIZE, (uint8_t *)&char_prop_read}},
/* Characteristic Value */
[IDX_CHAR_VAL_B] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&GATTS_CHAR_UUID_TEST_B, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
GATTS_DEMO_CHAR_VAL_LEN_MAX, sizeof(char_value), (uint8_t *)char_value}},
/* Characteristic Declaration */
[IDX_CHAR_C] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&character_declaration_uuid, ESP_GATT_PERM_READ,
CHAR_DECLARATION_SIZE, CHAR_DECLARATION_SIZE, (uint8_t *)&char_prop_write}},
/* Characteristic Value */
[IDX_CHAR_VAL_C] =
{{ESP_GATT_AUTO_RSP}, {ESP_UUID_LEN_16, (uint8_t *)&GATTS_CHAR_UUID_TEST_C, ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
GATTS_DEMO_CHAR_VAL_LEN_MAX, sizeof(char_value), (uint8_t *)char_value}},
};Profile处理函数
//创建属性表
esp_err_t create_attr_ret = esp_ble_gatts_create_attr_tab(gatt_db, gatts_if, HRS_IDX_NB, SVC_INST_ID);
if (create_attr_ret){
ESP_LOGE(GATTS_TABLE_TAG, "create attr table failed, error code = %x", create_attr_ret);
}
}
break;
case ESP_GATTS_CREAT_ATTR_TAB_EVT:{//创建属性表完成时
if (param->add_attr_tab.status != ESP_GATT_OK){
ESP_LOGE(GATTS_TABLE_TAG, "create attribute table failed, error code=0x%x", param->add_attr_tab.status);
}
else if (param->add_attr_tab.num_handle != HRS_IDX_NB){
ESP_LOGE(GATTS_TABLE_TAG, "create attribute table abnormally, num_handle (%d) \
doesn't equal to HRS_IDX_NB(%d)", param->add_attr_tab.num_handle, HRS_IDX_NB);
}
else {
ESP_LOGI(GATTS_TABLE_TAG, "create attribute table successfully, the number handle = %d\n",param->add_attr_tab.num_handle);
memcpy(heart_rate_handle_table, param->add_attr_tab.handles, sizeof(heart_rate_handle_table));
esp_ble_gatts_start_service(heart_rate_handle_table[IDX_SVC]);//启动服务
}
break;
}