网关

BLE Central（多连接）+ WiFi STA + 数据桥接

前置阅读：Hello BLE、STA 连接

学习目标

• 理解 BLE 网关的架构——BLE Central 连接多个 Peripheral → 数据汇聚 → WiFi 上报云端
• 掌握 BLE 多连接管理
• 理解与 SLE 网关的异同（模型差异、实现差异）
• 能够在 WS63 上实现一个连接多个传感器 + 上网的 BLE 网关

规格与功能

网关设备（WS63）作为 BLE Central 同时连接多个 BLE Peripheral 传感器，汇聚数据通过 WiFi 上报云端，并接收云端指令下发。

flowchart LR
    subgraph Sensors[传感器设备]
        Temp[温湿度 Peripheral<br/>BLE]
        Light[光照 Peripheral<br/>BLE]
        Relay[继电器 Peripheral<br/>BLE]
    end
    subgraph GW[WS63 网关]
        Central[BLE Central<br/>多连接]
        Bridge[数据桥接]
        WiFi[WiFi STA]
    end
    Cloud[云端 MQTT]

    Temp -->|Notify| Central
    Light -->|Notify| Central
    Central --> Bridge --> WiFi
    WiFi --> Cloud
    Cloud --> WiFi --> Bridge --> Central
    Central -->|Write| Relay

基本概念

BLE 网关 vs SLE 网关

	BLE 网关	SLE 网关
服务模型	GATT（Characteristic + CCCD）	SSAP（Property + operate_indication）
连接数	理论 8+，实际 ~4	最多 8
传感器接入	需要先写 CCCD 使能通知	直接接收 Notify/Indicate
吞吐量	~20-40 KB/s per link	~80-100 KB/s per link
手机兼容	✓ 原生支持	需要 SLE 芯片

架构设计完全一致——差异在无线层。如果传感器是 BLE 设备，选 BLE 网关；如果是 SLE 设备，选 SLE 网关。

多连接管理

#define MAX_PERIPHERALS 4

typedef struct {
    uint16_t conn_id;
    uint16_t data_char_handle;   // 数据通道 handle
    uint16_t ctrl_char_handle;   // 控制通道 handle
    uint8_t  online;
} peripheral_ctx_t;

涉及 API

API	用途
gap_ble_connect_remote_device()	BLE 多连接
gattc_discovery_service()	每个 Peripheral 的服务发现
gattc_write_req()	写 CCCD 使能通知 + 下发指令
gattc_register_callbacks()	接收多路 Notify
wifi_sta_connect()	WiFi 联网

案例操作指导

网关 + 多个 Peripheral 分别烧录 → Peripheral 先广播 → 网关后上电 → 逐一连接 + 写 CCCD → WiFi 联网 → 数据上报。

关键配置

参数	值	说明
BLE 连接数	3~4	BLE 多连接稳定值
CCCD 使能	连接后发现服务 + 写 CCCD=0x0001	每个 Peripheral 都要做
数据汇聚	消息队列	同 SLE 网关

代码详解

逐一连接 Peripheral

static void connect_next_peripheral(void)
{
    if (g_conn_index < g_peripheral_count) {
        gap_ble_connect_remote_device(&g_peripheral_addr[g_conn_index]);
    } else {
        // 全部连接完成 → 启动 WiFi 数据上报
        start_cloud_upload();
    }
}

// 连接回调
static void conn_state_cb(uint16_t conn_id, bd_addr_t *addr,
                           gap_ble_conn_state_t state)
{
    if (state == CONNECTED) {
        // 服务发现 → 找到数据通道 → 写 CCCD
        gattc_discovery_service(g_client_id, conn_id, NULL);
    } else if (state == DISCONNECTED) {
        peripheral_ctx_t *ctx = find_by_conn_id(conn_id);
        ctx->online = false;
    }
}

数据汇聚

static void notification_cb(uint8_t client_id, uint16_t conn_id,
                              gattc_handle_value_t *data, errcode_t status)
{
    peripheral_ctx_t *ctx = find_by_conn_id(conn_id);
    if (ctx == NULL) return;

    gateway_frame_t frame = {
        .source    = ctx->type,
        .conn_id   = conn_id,
        .data_len  = data->data_len,
    };
    memcpy(frame.data, data->data, data->data_len);

    osal_msg_queue_write_copy(g_upload_queue, &frame, sizeof(frame), 0);
}

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