diff --git a/docs/compose/spec/device-link.md b/docs/compose/spec/device-link.md
new file mode 100644
index 0000000..2ea96d1
--- /dev/null
+++ b/docs/compose/spec/device-link.md
@@ -0,0 +1,100 @@
+---
+feature: device-link
+status: delivered
+updated: 2026-09-16
+branch: feat/device-link
+commits: 353d936..033ece2
+---
+
+# Device Link / ConnectionHub（全链路统一连接层）
+
+## Report
+
+**What was built** — 在既有 DeviceLink 健康广播之上扩展为 ConnectionHub：`deviceLink` 统一持有
+WiFi IP、EtherCAT 网卡子串与 `ecatPost`，并保留 Owner/Client 快照。OTA（app.js）、CAN、
+can_monitor、motor、ecat_load、LAN9252 改为从 Hub 读端点/订在线布尔；BLE 仍经 `reportBle`
+上报。连接灯只覆盖布尔，不替换调用方语义文案。
+
+**Verification** —
+- `node --check` 全部改动 JS → PASS
+- `test_motor_transport.mjs` 58/58 PASS
+- `test_motor_refresh.mjs` 62/62 PASS
+- `test_ecat_autostart.mjs` 19/19 PASS
+- 独立评审后修复 3 个 critical：读路径 setIp 风暴、CAN 文案覆盖、嵌入页误标轮询离线
+
+**Journey log** —
+- 「共用 IP」≠「共用连接」——健康态必须有单一 Owner
+- Hub subscribe 只覆盖在线布尔，绝不替换调用方语义文案
+- 禁止在读路径调 setIp：Owner 会把每次 set-ip 当成立即重探
+- 嵌入 can.html 时 hub 不得写 fbPollStatus（那是 feedback 轮询自己的状态）
+## [S1] Problem
+
+多 iframe 保活后，各页仍**各自**判定「设备连上了没有」，只是共用一个 IP 字符串：
+
+- OTA 页轮询 `/system/status` → 顶栏「WiFi 已连接」
+- LAN9252 页轮询 `/spi/send` → 同一 IP 却显示「连接失败」
+- EtherCAT 状态/负载又是一条独立轮询，网卡子串在 4 处重复读 `localStorage`
+- BLE 在页内 GATT，其它页完全不知
+- CAN / can_monitor / motor 各有一套 `getBaseUrl` 包装
+
+用户直觉是「同一条设备连接」，实现却是 N 条互不证明的 HTTP/蓝牙会话和重复端点配置。
+
+## [S2] Design
+
+### 原则
+
+1. **外壳持有链路健康轮询**（tabs.html Owner），功能页不再各自判定「设备在线」。
+2. **BroadcastChannel**（`dcu-device-link`）广播快照；页内只订阅渲染。
+3. **端点配置只在 ConnectionHub**：IP（`dcu_esp_ip`）、网卡（`dcu_ecat_adapter`）读写集中。
+4. **命令仍页内发**，连接灯只认 DeviceLink 布尔（文案保留调用方语义）。
+5. BLE 为一等通道但单独适配：只广播状态，GATT 细节留在 `ble/*`。
+6. **外壳启动强制开总线**：Owner 首轮即 `status→open→motor/start`；成功后不再重复
+   `motor/start`，掉线后 10s 退避重试。有线 EtherCAT 与 WiFi 不争网卡。
+
+### ConnectionHub 客户端 API（`deviceLink`）
+
+| API | 用途 |
+|-----|------|
+| `subscribe` / `getSnapshot` / `channelOnline` | 健康快照 |
+| `getIp` / `setIp` / `wifiBaseUrl` | WiFi 端点 |
+| `getEcatAdapter` / `setEcatAdapter` | EtherCAT 网卡子串 |
+| `ecatPost(path, body, timeoutMs)` | 统一 `/ecat/api/*` 代理请求 |
+| `reportBle` | BLE 状态上报 |
+
+Owner 消息：`hello` / `snapshot` / `set-ip` / `ble-state`。
+
+### 接入
+
+| 位置 | 行为 |
+|------|------|
+| `tabs.html` | Owner |
+| Owner `bootstrapEcatBus` | 外壳启动即 open+motor/start，不必等电机页切 EtherCAT |
+| `connection.js` | 快照新鲜时覆盖 connected 布尔 |
+| `app.js` | IP/baseURL 走 `deviceLink`（保留 `#espIp` 输入回退） |
+| `can/dbc.js` + `can.js` | setDeviceIp 广播；顶栏灯订阅 hub |
+| `can_monitor.js` | baseURL 走 base-url/hub；灯订阅 hub |
+| `motor/main.js` | IP 订阅 hub 同步 `state.ip` |
+| `motor/transport-ecat.js` | 网卡子串经 hub 读写 |
+| `ota/ecat_load.js` | `deviceLink.ecatPost` |
+| `lab/lan9252_pm.html` | 灯订阅 hub；open 网卡经 hub |
+| `lab/spi_test.html` | 共享 IP 键（自包含页不深耦合请求层） |
+| `js/ble/gatt.js` | 通知成功后 reportBle(true)，失败/断 false |
+
+## [S3] Out of Scope
+
+- 不串行化 SPI/CAN/OTA 命令队列
+- 不迁 SharedWorker
+- 不改固件协议
+- 不把 BLE GATT 强行对齐 HTTP/ECAT 请求接口
+- spi_test 保持可整文件删除，不注入业务请求逻辑
+
+## Tasks
+
+- [x] T1: device-link.js Owner+Client + BC 协议 (covers: S2)
+- [x] T2: tabs.html 启动 Owner (covers: S2)
+- [x] T3: OTA connection.js 接入 DeviceLink (covers: S2)
+- [x] T4: LAN9252 灯与 SPI 文案 (covers: S2)
+- [x] T5: BLE 状态上报 (covers: S2)
+- [x] T6: 语法检查 + 评审修复 (covers: S2)
+- [x] T7: Hub 扩展 wifiBaseUrl/ecatPost/adapter API (covers: S2)
+- [x] T8: OTA/CAN/motor/ecat_load/lab 迁到 Hub 端点 (covers: S2)
diff --git a/esp32_server.py b/esp32_server.py
index f8d656a..50620df 100644
--- a/esp32_server.py
+++ b/esp32_server.py
@@ -157,7 +157,21 @@ g_ecat_port = None   # 记住上次探到的端口, 避免每次请求都从 809
 #  2) 拉起时**必须带 --parent-pid**: 让 native 在本服务退出后自我了断,
 #     不留孤儿进程占着 Npcap 适配器和端口。
 #  3) 不再需要 venv/pythonw —— 单文件 exe, 无 Python 运行时依赖。
-ECAT_DIR = os.path.normpath(os.path.join(BASE_DIR, "..", "ecat"))
+def _resolve_ecat_dir(base_dir):
+    """定位 tools/ecat（ecat_native.exe 的仓库，与本仓库平级）。
+
+    从 git worktree（.../tools/ESP32/.worktrees/<slug>）启动时，BASE_DIR 的
+    上一级是 .worktrees 而不是 tools，直接 join("..","ecat") 会拼成
+    .../ESP32/.worktrees/ecat，找不到 exe。先走回主检出再取兄弟目录。
+    """
+    d = os.path.abspath(base_dir)
+    parent = os.path.dirname(d)
+    if os.path.basename(parent) == ".worktrees":
+        d = os.path.dirname(parent)  # → .../tools/ESP32 主检出
+    return os.path.normpath(os.path.join(d, "..", "ecat"))
+
+
+ECAT_DIR = _resolve_ecat_dir(BASE_DIR)
 ECAT_NATIVE_EXE = os.path.join(ECAT_DIR, "build_native", "ecat_native.exe")
 g_ecat_child = None      # 由本服务拉起的 ecat 服务子进程(复用已有实例时为 None)
 g_ecat_log_fp = None     # native stdout 落盘句柄(见 _ecat_autostart 内注释)
diff --git a/js/app.js b/js/app.js
index 98a10a3..9135900 100644
--- a/js/app.js
+++ b/js/app.js
@@ -34,6 +34,7 @@ import {
   updateStagesFromRelayState, updateSystemStatusUi
 } from './ota/stages.js';
 import { startEcatLoadPoller } from './ota/ecat_load.js';
+import { deviceLink } from './common/device-link.js';
 import {
   handleFileSelect, pickFileViaFSAPI, setupDropZone,
   parseIntelHex, isIntelHexText, convertHexFileToBin,
@@ -50,14 +51,15 @@ function formatPercent(value) {
   if (!Number.isFinite(value)) return '--';
   return value.toFixed(1).replace(/\.0$/, '') + '%';
 }
+/** 设备 IP：优先本页 #espIp 输入框，否则 ConnectionHub。
+ *  只在值变化时 setIp——Owner 会把 set-ip 当成立即重探，读路径每次写会 1Hz 风暴。 */
 function getEspIp() {
   var el = document.getElementById('espIp');
   var ip = el && el.value ? el.value.trim() : '';
-  if (!ip) {
-    try { ip = (localStorage.getItem('dcu_esp_ip') || '').trim(); } catch (_) {}
+  if (!ip) return deviceLink.getIp();
+  if (ip !== deviceLink.getIp()) {
+    try { deviceLink.setIp(ip); } catch (_) {}
   }
-  if (!ip) ip = '192.168.31.127';
-  try { localStorage.setItem('dcu_esp_ip', ip); } catch (_) {}
   return ip;
 }
 function getBaseUrl() {
@@ -277,11 +279,11 @@ startEcatLoadPoller();
 var ipInput = document.getElementById('espIp');
 if (ipInput) {
   try {
-    var savedIp = localStorage.getItem('dcu_esp_ip');
+    var savedIp = deviceLink.getIp();
     if (savedIp && savedIp.trim()) ipInput.value = savedIp.trim();
   } catch (_) {}
   ipInput.addEventListener('change', function () {
-    try { localStorage.setItem('dcu_esp_ip', ipInput.value.trim() || '192.168.31.127'); } catch (_) {}
+    try { deviceLink.setIp(ipInput.value.trim() || '192.168.31.127'); } catch (_) {}
     window.consecutivePollFailures = 0;
     addLog('I', '系统', 'IP 已修改，重新启动轮询...');
     if (!window.statusPollInFlight) {
diff --git a/js/ble/gatt.js b/js/ble/gatt.js
index d8e104c..25282e9 100644
--- a/js/ble/gatt.js
+++ b/js/ble/gatt.js
@@ -33,6 +33,7 @@ import {
 import { setBleStage, setBleStageError, setBleStageText, setBleStageStatus, resetBleStages } from './stages.js';
 import { setProgress, updateProgressFromAck } from './transfer.js';
 import { showBleVerifyInfo } from './verify.js';
+import { deviceLink } from '../common/device-link.js';
 import {
   clearOtaResultWaiter,
   resolveOtaResult,
@@ -109,13 +110,16 @@ export async function connectBle() {
     // ★ enableNotifications 内部已包含重试 + 主动断开逻辑；
     //   若返回时仍为 false，说明连接半死，UI 已被断开事件重置，不要继续推进到 Stage 3
     if (!state.notificationsEnabled) {
+      try { deviceLink.reportBle(false, ''); } catch (_) {}
       bleLog('BLE', '连接就绪但 DATA_OUT 通知开启失败，等待用户重连', 'E');
       return;
     }
+    try { deviceLink.reportBle(true, device.name || ''); } catch (_) {}
     // Mark stages 1-2 as done
     setBleStage(3, '', null);
     setBleStageText('BLE 连接就绪，请选择固件文件');
   } catch (err) {
+    try { deviceLink.reportBle(false, ''); } catch (_) {}
     bleLog('BLE', `连接失败: ${err.message}`, 'E');
     if (err.name !== 'NotFoundError') {
       setBleStageError(err.message);
@@ -129,6 +133,7 @@ export async function connectBle() {
 export function onDisconnected() {
   bleLog('BLE', '设备已断开', 'W');
   var wasExpected = state.expectedReboot;
+  try { deviceLink.reportBle(false, ''); } catch (_) {}
   resetUiAfterDisconnect();
   if (wasExpected && state.device) {
     // 是主动重启引起的断开，启动自动重连
@@ -151,6 +156,7 @@ export async function disconnectBle() {
   if (state.device && state.device.gatt && state.device.gatt.connected) {
     state.device.gatt.disconnect();
   }
+  try { deviceLink.reportBle(false, ''); } catch (_) {}
   resetUiAfterDisconnect();
 }
 
diff --git a/js/can.js b/js/can.js
index c3c3ee0..52beb77 100644
--- a/js/can.js
+++ b/js/can.js
@@ -53,6 +53,7 @@ import {
 import { escapeHtml as sanitizeHtml, formatUptime } from './common/utils.js';
 import { showToast } from './common/toast.js';
 import { initCanMonitor } from './can_monitor.js';
+import { deviceLink } from './common/device-link.js';
 
 // ==================== 本地工具 ====================
 // 原 can.js 的 formatUptime 输出格式与 common/utils.js 略有差异（d>0 时只到 h），
@@ -413,6 +414,12 @@ function init() {
   setTimeout(testConnection, 150);
   /* 周期性刷新顶栏 STA/IP/RSSI/运行时间（与监控 1Hz 解耦，避免重复 pill） */
   setInterval(testConnection, 5000);
+  /* ConnectionHub 快照只覆盖在线布尔，不改 testConnection 写的语义文案（STA/HTTP…） */
+  deviceLink.subscribe(function (s) {
+    if (!s || !s.ts || (Date.now() - s.ts) >= 5000) return;
+    var on = !!(s.links && s.links.esp32 && s.links.esp32.online);
+    if (el.canConnPill) el.canConnPill.className = 'pill ' + (on ? 'online' : 'offline');
+  });
   /* 右侧抽屉：CAN 接收监控 */
   initCanMonitor();
 }
diff --git a/js/can/dbc.js b/js/can/dbc.js
index da70de7..994de84 100644
--- a/js/can/dbc.js
+++ b/js/can/dbc.js
@@ -9,6 +9,7 @@
 import {
   DEFAULT_ESP_IP, getSavedDeviceIp, saveDeviceIp
 } from '../common/base-url.js';
+import { deviceLink } from '../common/device-link.js';
 
 // ==================== 共享状态 ====================
 export var state = {
@@ -46,11 +47,12 @@ export function getDeviceIp() {
   return DEFAULT_ESP_IP;
 }
 
-/** @description 记住设备 IP（status 回报或其它页写入）。 */
+/** @description 记住设备 IP（status 回报或其它页写入），并广播给 ConnectionHub。 */
 export function setDeviceIp(ip) {
   if (!ip || !String(ip).trim()) return;
   var v = String(ip).trim();
   saveDeviceIp(v);
+  try { deviceLink.setIp(v); } catch (_) {}
   if (el.toolIp) el.toolIp.value = v;
 }
 
diff --git a/js/can_monitor.js b/js/can_monitor.js
index 48d9ee2..5983ce4 100644
--- a/js/can_monitor.js
+++ b/js/can_monitor.js
@@ -3,6 +3,8 @@
  */
 import { showToast } from './common/toast.js';
 import { escapeHtml } from './common/utils.js';
+import { getBaseUrl as hubBaseUrl } from './common/base-url.js';
+import { deviceLink } from './common/device-link.js';
 
 var state = { fbTimer: null, fbInFlight: false };
 
@@ -52,20 +54,15 @@ function cacheElements() {
   ids.forEach(function (id) { el[id] = document.getElementById(id); });
 }
 
+/** WiFi 端点：优先本页输入框，否则 ConnectionHub 共享 IP（dcu_esp_ip）。 */
 function getBaseUrl() {
-  var ip = '';
-  if (el.monIp && el.monIp.value) {
-    ip = el.monIp.value.trim();
-  } else if (el.toolIp && el.toolIp.value) {
-    ip = el.toolIp.value.trim();
-  } else {
-    try {
-      var saved = localStorage.getItem('dcu_esp_ip');
-      if (saved && saved.trim()) ip = saved.trim();
-    } catch (_) {}
+  if (el.monIp && el.monIp.value && el.monIp.value.trim()) {
+    return 'http://' + el.monIp.value.trim();
   }
-  if (!ip) ip = '192.168.31.127';
-  return 'http://' + ip;
+  if (el.toolIp && el.toolIp.value && el.toolIp.value.trim()) {
+    return 'http://' + el.toolIp.value.trim();
+  }
+  return hubBaseUrl();
 }
 
 function setConnState(ok, text) {
@@ -304,6 +301,15 @@ export function initCanMonitor() {
   setConnState(false, '未连接');
   if (!state.bound) {
     state.bound = true;
+    /* ConnectionHub：只覆盖独立页 monConn 灯的布尔；
+     * 嵌入 can.html 时无 monConnPill，不得碰 fbPollStatus（那是 /can/feedback 自己的轮询态）。 */
+    deviceLink.subscribe(function (s) {
+      if (!el.monConnPill) return;
+      if (!s || !s.ts || (Date.now() - s.ts) >= 5000) return;
+      var on = !!(s.links && s.links.esp32 && s.links.esp32.online);
+      el.monConnPill.className = 'pill ' + (on ? 'online' : 'offline');
+      if (el.monConnIndicator) el.monConnIndicator.className = 'conn-indicator ' + (on ? 'ok' : 'err');
+    });
     if (el.monTestBtn) el.monTestBtn.addEventListener('click', testConnection);
     if (el.monIp) el.monIp.addEventListener('change', testConnection);
     /* 嵌入 can.html 时 IP 与发送台共用 */
diff --git a/js/common/connection.js b/js/common/connection.js
index 7795986..5b7d2d5 100644
--- a/js/common/connection.js
+++ b/js/common/connection.js
@@ -18,6 +18,7 @@ import { showToast } from './toast.js';
 import {
   appendHeapLowRecords, loadHeapLowHistory, clearHeapLowHistory, HEAP_HISTORY_MAX
 } from './heap-low-history.js';
+import { deviceLink } from './device-link.js';
 
 // ==================== 渲染缓存（性能） ====================
 // /system/status 每 1s（中继期 400ms）刷一次 UI。此前每轮全量 innerHTML 重建
@@ -55,6 +56,16 @@ function setWidthIfChanged(el, widthStr) {
 
 // ==================== 连接管理 ====================
 export function updateConnectionUi(connected, text) {
+  /* DeviceLink 统一层：外壳 Owner 广播的新鲜快照优先于本页局部轮询结论，
+     避免 OTA「已连接」与 LAN9252「失败」同屏分裂。独立直开页无快照则用参数。 */
+  try {
+    var snap = deviceLink.getSnapshot();
+    if (snap && snap.ts && (Date.now() - snap.ts) < 5000) {
+      /* 只覆盖在线布尔，保留调用方语义文案（设备忙/诊断中/STA…） */
+      connected = !!snap.links.esp32.online;
+      if (!text) text = connected ? '已连接' : '离线';
+    }
+  } catch (_) {}
   var label = text || (connected ? '已连接' : '未连接');
   // 仅顶栏连接胶囊（下方连接卡不再重复显示文案）
   var pc = getEl('pillConn');
diff --git a/js/common/device-link.js b/js/common/device-link.js
new file mode 100644
index 0000000..190f1ac
--- /dev/null
+++ b/js/common/device-link.js
@@ -0,0 +1,375 @@
+/**
+ * device-link.js — 全链路连接中心（ConnectionHub）
+ *
+ * 统一管理页面上的 WiFi / EtherCAT / BLE 三条链路：
+ *   - 健康轮询：外壳 Owner 常驻拉 ESP32 /system/status 与 EtherCAT status+load
+ *   - 端点配置：设备 IP（dcu_esp_ip）、网卡子串（dcu_ecat_adapter）只在此读写
+ *   - 通道适配：wifiBaseUrl / ecatPost 供各页复用，禁止再散落 localStorage
+ *
+ * 角色：
+ *   - Owner：tabs.html 加载前设 window.__dcuDeviceLinkOwner = true
+ *   - Client：任意页 import { deviceLink }
+ * 独立直开页无 Owner 时，client 仍可读 IP / 发 ecatPost，只是无跨页快照。
+ *
+ * 命令仍由业务页自己发；连接灯只认本层健康态（布尔优先，文案保留调用方语义）。
+ */
+"use strict";
+
+import {
+  getDeviceIp, saveDeviceIp, getBaseUrl as baseUrlFromIp
+} from "./base-url.js";
+
+var CH_NAME = "dcu-device-link";
+var ESP32_FAIL_ONLINE = 3;      /* 连续失败 ≥3 判离线 */
+var ESP32_POLL_MS = 1000;
+var ECAT_POLL_MS = 2000;
+var ECAT_BUS_RETRY_MS = 10000;  /* 开总线失败后的重试间隔 */
+var LS_ECAT_PERIOD = "dcu_ecat_period_ms";
+var LS_ECAT_SPIN = "dcu_ecat_spin";
+var LS_ECAT_ADAPTER = "dcu_ecat_adapter";
+var DEFAULT_ECAT_ADAPTER = "I210";
+
+function nowMs() { return Date.now(); }
+
+function readIp() {
+  return getDeviceIp();
+}
+
+function writeIp(ip) {
+  saveDeviceIp(ip);
+}
+
+function readAdapter() {
+  try {
+    var s = localStorage.getItem(LS_ECAT_ADAPTER);
+    if (s && s.trim()) return s.trim();
+  } catch (_) {}
+  return DEFAULT_ECAT_ADAPTER;
+}
+
+function writeAdapter(substr) {
+  if (!substr || !String(substr).trim()) return;
+  try { localStorage.setItem(LS_ECAT_ADAPTER, String(substr).trim()); } catch (_) {}
+}
+
+/**
+ * 统一 /ecat/api/* 代理请求（同源，esp32_server 转发到 ecat_native）。
+ * @param {string} path 相对路径，如 "status" / "app/load" / "open"
+ * @param {object} body JSON body，缺省 {}
+ * @param {number} timeoutMs 默认 5000
+ * @returns {Promise<object>} 解析后的 JSON
+ */
+async function ecatPost(path, body, timeoutMs) {
+  var p = String(path || "").replace(/^\/+/, "");
+  var resp = await fetch("/ecat/api/" + p, {
+    method: "POST",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify(body || {}),
+    cache: "no-store",
+    signal: AbortSignal.timeout(timeoutMs || 5000)
+  });
+  var text = await resp.text();
+  var json = {};
+  try { json = text ? JSON.parse(text) : {}; } catch (_) {
+    throw new Error("响应非合法 JSON");
+  }
+  if (!resp.ok) {
+    var err = new Error("HTTP " + resp.status);
+    err.status = resp.status;
+    err.json = json;
+    throw err;
+  }
+  return json;
+}
+
+function emptySnapshot() {
+  return {
+    ts: 0,
+    ip: readIp(),
+    links: {
+      esp32: { online: false, ageMs: -1, failStreak: 0 },
+      ecat:  { online: false, busOpen: false, op: false, loop: false,
+               loadValid: false, loadPerm: 0, ageMs: -1 },
+      ble:   { online: false, deviceName: "", owner: null }
+    },
+    esp32Status: null
+  };
+}
+
+/* ───────────────────────── Owner ───────────────────────── */
+
+function createOwner() {
+  var ch = null;
+  try { ch = new BroadcastChannel(CH_NAME); } catch (_) { ch = null; }
+  var snap = emptySnapshot();
+  var esp32Fails = 0;
+  var lastEsp32OkAt = 0;
+  var esp32Timer = null;
+  var ecatTimer = null;
+  var stopped = false;
+  /* 外壳启动即强制拉起总线（open + motor/start），不必等电机页切 EtherCAT。
+   * 成功后不再重复 motor/start；掉线后按 ECAT_BUS_RETRY_MS 退避重试。 */
+  var ecatBusReady = false;
+  var ecatBusBusy = false;
+  var ecatBusNextTryAt = 0;
+
+  function publish() {
+    snap.ts = nowMs();
+    snap.ip = readIp();
+    if (ch) {
+      try { ch.postMessage({ type: "snapshot", snap: snap }); } catch (_) {}
+    }
+  }
+
+  function setEsp32(status, ok) {
+    if (ok) {
+      esp32Fails = 0;
+      lastEsp32OkAt = nowMs();
+      snap.links.esp32.online = true;
+      snap.links.esp32.ageMs = 0;
+      snap.esp32Status = status || null;
+    } else {
+      esp32Fails++;
+      snap.links.esp32.failStreak = esp32Fails;
+      snap.links.esp32.ageMs = lastEsp32OkAt ? (nowMs() - lastEsp32OkAt) : -1;
+      if (esp32Fails >= ESP32_FAIL_ONLINE) snap.links.esp32.online = false;
+    }
+    snap.links.esp32.failStreak = esp32Fails;
+    publish();
+  }
+
+  function pollEsp32() {
+    if (stopped) return;
+    var ac = null;
+    try { ac = new AbortController(); } catch (_) {}
+    var tmo = null;
+    fetch(baseUrlFromIp() + "/system/status" + (window._memLayout ? "" : "?layout=1"), {
+      signal: ac ? ac.signal : undefined,
+      cache: "no-store"
+    }).then(function (r) {
+      if (!r.ok) throw new Error("HTTP " + r.status);
+      return r.json();
+    }).then(function (j) {
+      if (ac) { clearTimeout(tmo); }
+      setEsp32(j, true);
+    }).catch(function () {
+      if (ac) { clearTimeout(tmo); }
+      setEsp32(null, false);
+    }).then(function () {
+      esp32Timer = setTimeout(pollEsp32, ESP32_POLL_MS);
+    });
+    if (ac) {
+      tmo = setTimeout(function () { try { ac.abort(); } catch (_) {} }, 4000);
+    }
+  }
+
+  /**
+   * 开总线：status →（未开则）open 网卡 → motor/start 进 OP + 起 PDO 循环。
+   * 与 motor/transport-ecat ensureOpen/ensureStarted 同源，由外壳 Owner 在
+   * 控制台启动时强制执行，用户不必先去电机页把链路切到 EtherCAT。
+   */
+  function bootstrapEcatBus() {
+    if (stopped || ecatBusBusy) return;
+    var now = nowMs();
+    if (ecatBusReady) return;
+    if (now < ecatBusNextTryAt) return;
+    ecatBusBusy = true;
+    ecatBusNextTryAt = now + ECAT_BUS_RETRY_MS;
+
+    var adapter = readAdapter();
+    var body = {};
+    try {
+      var v = parseFloat(localStorage.getItem(LS_ECAT_PERIOD));
+      if (v > 0) body.period_ms = v;
+      var sp = localStorage.getItem(LS_ECAT_SPIN);
+      if (sp === "0") body.spin = false;
+      else if (sp === "1") body.spin = true;
+    } catch (_) {}
+
+    ecatPost("status", {}, 6000).then(function (st) {
+      var open = !!(st && st.ok);
+      return open ? Promise.resolve(st)
+        : ecatPost("open", { substr: adapter }, 20000);
+    }).then(function (r) {
+      if (r && r.ok === false) {
+        throw new Error((r.log && r.log.join(" / ")) || "open 失败");
+      }
+      return ecatPost("motor/start", body, 30000);
+    }).then(function (r) {
+      if (r && r.ok === false) {
+        throw new Error((r.log && r.log.join(" / ")) || "motor/start 失败");
+      }
+      ecatBusReady = true;
+    }).catch(function () {
+      /* 网线没插/从站未上电：退避后由 pollEcat 再触发 */
+    }).then(function () {
+      ecatBusBusy = false;
+    });
+  }
+
+  function pollEcat() {
+    if (stopped) return;
+    var stP = ecatPost("status", {}, 4000).catch(function () { return null; });
+    var ldP = ecatPost("app/load", {}, 4000).catch(function () { return null; });
+
+    Promise.all([stP, ldP]).then(function (arr) {
+      var st = arr[0], ld = arr[1];
+      var e = snap.links.ecat;
+      e.online = !!(st && st.ok && st.slave);
+      e.busOpen = !!(st && st.ok);
+      /* native status 不直接给 op/loop；用 load valid + slave state 粗判 */
+      e.op = !!(st && st.slave && st.slave.state != null && (st.slave.state & 0x0F) === 8);
+      e.loadValid = !!(ld && ld.ok && ld.valid === true
+        && Number.isFinite(ld.age_ms) && ld.age_ms >= 0 && ld.age_ms <= 3000);
+      e.loop = e.loadValid || e.op;
+      e.loadPerm = (ld && Number.isFinite(ld.load_perm)) ? ld.load_perm : 0;
+      e.ageMs = (ld && Number.isFinite(ld.age_ms)) ? ld.age_ms : -1;
+      if (e.busOpen && e.loop) ecatBusReady = true;
+      else if (ecatBusReady && !e.busOpen) ecatBusReady = false;  /* 总线掉了 → 允许重开 */
+      publish();
+      bootstrapEcatBus();
+    }).catch(function () {
+      /* 字段访问/异常不得让 ECAT 轮询永久停摆 */
+    }).then(function () {
+      if (!stopped) ecatTimer = setTimeout(pollEcat, ECAT_POLL_MS);
+    });
+  }
+
+  function onMsg(ev) {
+    var m = ev && ev.data;
+    if (!m || !m.type) return;
+    if (m.type === "hello") { publish(); return; }
+    if (m.type === "set-ip") {
+      writeIp(m.ip);
+      try {
+        fetch(baseUrlFromIp() + "/system/status", {
+          cache: "no-store",
+          signal: AbortSignal.timeout(2000)
+        }).then(function (r) { return r.json(); })
+          .then(function (j) { setEsp32(j, true); })
+          .catch(function () { setEsp32(null, false); });
+      } catch (_) {}
+      return;
+    }
+    if (m.type === "ble-state") {
+      snap.links.ble.online = !!m.online;
+      snap.links.ble.deviceName = m.deviceName || "";
+      snap.links.ble.owner = m.owner || (m.online ? "page" : null);
+      publish();
+      return;
+    }
+  }
+
+  if (ch) ch.addEventListener("message", onMsg);
+  pollEsp32();
+  pollEcat();
+  bootstrapEcatBus();
+  publish();
+
+  return {
+    stop: function () {
+      stopped = true;
+      if (esp32Timer) clearTimeout(esp32Timer);
+      if (ecatTimer) clearTimeout(ecatTimer);
+      if (ch) { try { ch.close(); } catch (_) {} }
+    }
+  };
+}
+
+/* ───────────────────────── Client ───────────────────────── */
+
+function createClient() {
+  var ch = null;
+  try { ch = new BroadcastChannel(CH_NAME); } catch (_) { ch = null; }
+  var listeners = [];
+  var last = null;
+
+  function emit() {
+    for (var i = 0; i < listeners.length; i++) {
+      try { listeners[i](last); } catch (_) {}
+    }
+  }
+
+  if (ch) {
+    ch.addEventListener("message", function (ev) {
+      var m = ev && ev.data;
+      if (!m || m.type !== "snapshot" || !m.snap) return;
+      last = m.snap;
+      emit();
+    });
+    try { ch.postMessage({ type: "hello" }); } catch (_) {}
+  }
+
+  function applyLocalBle(online, deviceName) {
+    if (last) {
+      last.links.ble.online = !!online;
+      last.links.ble.deviceName = deviceName || "";
+      last.links.ble.owner = online ? "iframe" : null;
+      last.ts = nowMs();
+      emit();
+    }
+  }
+
+  return {
+    /* ── 快照 ── */
+    getSnapshot: function () { return last; },
+    subscribe: function (fn) {
+      if (typeof fn !== "function") return function () {};
+      listeners.push(fn);
+      if (last) { try { fn(last); } catch (_) {} }
+      return function () {
+        var i = listeners.indexOf(fn);
+        if (i >= 0) listeners.splice(i, 1);
+      };
+    },
+    /** 指定通道当前是否在线；无快照时回退 false（调用方自行降级） */
+    channelOnline: function (name) {
+      if (!last || !last.links) return false;
+      var L = last.links[name];
+      return !!(L && L.online);
+    },
+
+    /* ── WiFi 端点 ── */
+    setIp: function (ip) {
+      writeIp(ip);
+      if (ch) { try { ch.postMessage({ type: "set-ip", ip: readIp() }); } catch (_) {} }
+    },
+    getIp: function () { return readIp(); },
+    wifiBaseUrl: function () { return baseUrlFromIp(); },
+
+    /* ── EtherCAT 端点与请求 ── */
+    getEcatAdapter: function () { return readAdapter(); },
+    setEcatAdapter: function (substr) {
+      writeAdapter(substr);
+      return readAdapter();
+    },
+    ecatPost: ecatPost,
+
+    /* ── BLE 状态上报 ── */
+    reportBle: function (online, deviceName) {
+      var payload = {
+        type: "ble-state",
+        online: !!online,
+        deviceName: deviceName || "",
+        owner: "iframe"
+      };
+      if (ch) { try { ch.postMessage(payload); } catch (_) {} }
+      applyLocalBle(online, deviceName);
+    },
+
+    hasOwner: function () { return !!last; }
+  };
+}
+
+/* ───────────────────────── bootstrap ───────────────────────── */
+
+var deviceLink;
+try {
+  if (window.__dcuDeviceLinkOwner) {
+    window.__dcuDeviceLinkInstance = createOwner();
+  }
+} catch (_) {}
+
+deviceLink = createClient();
+export { deviceLink, ecatPost, readAdapter as getEcatAdapter, writeAdapter as setEcatAdapter };
+export default deviceLink;
diff --git a/js/motor/main.js b/js/motor/main.js
index 12ba0d9..04655d0 100644
--- a/js/motor/main.js
+++ b/js/motor/main.js
@@ -35,13 +35,14 @@
 
 /* IP 存取公共实现（localStorage dcu_esp_ip，与 OTA/CAN 页共用） */
 import {
-  DEFAULT_ESP_IP, getDeviceIp, saveDeviceIp
+  DEFAULT_ESP_IP, saveDeviceIp
 } from "../common/base-url.js";
 import { escapeHtml } from "../common/utils.js";
 /* 传输层：WiFi(HTTP) / EtherCAT(过程数据) 二选一，业务逻辑完全共用 */
 import {
   createTransport, loadTransportId, saveTransportId
 } from "./transport.js";
+import { deviceLink } from "../common/device-link.js";
 /* 刷新速度「每链路一份」的纯逻辑（默认值/钳制/旧数据迁移），
  * 抽出去是为了能脱离 DOM 自测，见 refresh-rate.js 头注释。 */
 import {
@@ -167,9 +168,9 @@ const $ = (s) => document.querySelector(s);
 const nodeListEl = $("#nodeList");
 
 /* ─── 工具函数 ─── */
-/** 读取主页写入的共享设备 IP（localStorage dcu_esp_ip） */
+/** 读取 ConnectionHub / base-url 共享设备 IP（dcu_esp_ip） */
 function getSharedDeviceIp() {
-  return getDeviceIp();
+  return deviceLink.getIp();
 }
 
 /* ─── 输入持久化：刷新/重开页面后恢复上次输入 ───
@@ -267,6 +268,7 @@ function setSharedDeviceIp(ip) {
   if (!ip || !String(ip).trim()) return;
   const v = String(ip).trim();
   state.ip = v;
+  try { deviceLink.setIp(v); } catch (_) {}
   saveDeviceIp(v);
   const label = $("#ipLabel");
   if (label) label.textContent = "IP " + v;
@@ -4011,8 +4013,17 @@ const scopeSys = (() => {
 /* ═══════════════════════ 初始化 ═══════════════════════ */
 /* 传输必须最先建：updateConnUi / renderStatusPanel 等都会读 state.tp。 */
 useTransport(loadTransportId());
-/* 本页不提供连接配置：WiFi 链路读主页 localStorage dcu_esp_ip，进入后自动探测 */
+/* 本页不提供连接配置：WiFi 链路读 ConnectionHub 共享 IP，进入后自动探测 */
 state.ip = getSharedDeviceIp();
+/* 其它页改 IP 后同步本页缓存（外壳 Owner 会再广播 set-ip 后的快照） */
+deviceLink.subscribe(function (snap) {
+  if (!snap || !snap.ip) return;
+  if (snap.ip !== state.ip) {
+    state.ip = snap.ip;
+    const label = $("#ipLabel");
+    if (label) label.textContent = "IP " + state.ip;
+  }
+});
 /* 先恢复用户上次输入（modeSelect / 目标值 / PID / 通道 / 选中节点），
  * 再 applyModeVisibility 才能让保存的 mode 决定字段可见性。 */
 loadUiState();
diff --git a/js/motor/transport-ecat.js b/js/motor/transport-ecat.js
index 936a1ce..9917d3e 100644
--- a/js/motor/transport-ecat.js
+++ b/js/motor/transport-ecat.js
@@ -35,6 +35,7 @@
 /* 判活阈值纯逻辑（随实测 seq 间隔自适应）住在 refresh-rate.js 的
  * 「ECAT 槽判活阈值」一节，纯函数以便脱离 DOM 自测。 */
 import { staleLimitMs } from "./refresh-rate.js";
+import { deviceLink } from "../common/device-link.js";
 
 /** 单个 PDO 周期回传的状态槽数。
  *  固件 1.6.21 起段 2 密排整轮：一拍带齐总线电机（最多 9），空槽不占位。
@@ -94,14 +95,8 @@ function fmtPeriod(ms) {
 export function createEcatTransport(ctx) {
   const { recordSlow, isTransient } = ctx;
 
-  /* 网卡匹配子串。与 ecat.html 的输入框默认值一致（I210，2026-09 网卡 I226→I210）；
-   * 存 localStorage 以便换网卡后不用每次重设。 */
-  const LS_ADAPTER = "dcu_ecat_adapter";
-  let adapterSubstr = "I210";
-  try {
-    const saved = localStorage.getItem(LS_ADAPTER);
-    if (saved && saved.trim()) adapterSubstr = saved.trim();
-  } catch (_) {}
+  /* 网卡匹配子串：统一从 ConnectionHub 读写（dcu_ecat_adapter），与 OTA/lab 页共用。 */
+  let adapterSubstr = deviceLink.getEcatAdapter();
 
   /* ── 传输内部累积状态 ──
    * 这些都是"WiFi 侧由固件/GD32 代为缓存、EtherCAT 侧必须前端自己攒"的东西。 */
@@ -530,7 +525,7 @@ export function createEcatTransport(ctx) {
       const v = String(substr || "").trim();
       if (!v || v === adapterSubstr) return false;
       adapterSubstr = v;
-      try { localStorage.setItem(LS_ADAPTER, v); } catch (_) {}
+      try { deviceLink.setEcatAdapter(v); } catch (_) {}
       started = false;
       lastSnapshot = null;
       try { await api("close", {}, 8000); } catch (_) { /* 没连接时无所谓 */ }
diff --git a/js/ota/ecat_load.js b/js/ota/ecat_load.js
index 9a02518..62ffdc1 100644
--- a/js/ota/ecat_load.js
+++ b/js/ota/ecat_load.js
@@ -16,7 +16,10 @@
  *     自动停循环退回 INIT），负载值不再滚动，视为过期；
  *   - 代理 503 —— ecat_native 没在跑。退避轮询（1s→5s→30s），避免不用 EtherCAT
  *     的用户按 1Hz 反复触发 esp32_server 的自动拉起逻辑。
+ *
+ * 请求统一走 ConnectionHub（device-link.ecatPost），与 Owner 健康轮询同源。
  */
+import { deviceLink } from '../common/device-link.js';
 
 var POLL_MS = 1000;      /* 正常轮询节拍（负载窗口 1s 一滚，再快没意义） */
 var STALE_MS = 3000;     /* 超过 3 个窗口没刷新即视为过期 */
@@ -38,8 +41,8 @@ function setTitle(node, title) {
 }
 
 var TIP_BASE = 'DCU_APP CPU 负载率：中断+非延迟处理(任务派发/OTA中继)占墙钟比，不含常开轮询与空转；EtherCAT 输入 PDO 段5，1s 窗口';
-var TIP_OFF = TIP_BASE + '；当前不可用：需要 ECAT 总线已打开且过程数据循环在跑'
-            + '（如打开电机控制页选 EtherCAT 传输），且 DCU_APP 固件 >= 1.5.61。';
+var TIP_OFF = TIP_BASE + '；当前不可用：控制台外壳启动时会自动 open+motor/start；'
+            + '若仍为 --，检查网线/从站供电，或手动打开电机控制页选 EtherCAT。';
 
 /** @description 把 /api/app/load 的 JSON 渲染到 #mGd32Load。返回值是否有效（驱动退避）。 */
 function render(d) {
@@ -73,8 +76,7 @@ async function tick() {
   if (!node) return;                 /* 页面上没有该指标就不再调度 */
   var ok = false;
   try {
-    var resp = await fetch('/ecat/api/app/load', { method: 'POST', body: '{}' });
-    if (resp.ok) ok = render(await resp.json());
+    ok = render(await deviceLink.ecatPost('app/load', {}, 3000));
   } catch (_) { /* 代理/后端离线，走退避 */ }
   if (!ok) {
     failCount++;
diff --git a/lab/lan9252_pm.html b/lab/lan9252_pm.html
index 29c3689..90039cb 100644
--- a/lab/lan9252_pm.html
+++ b/lab/lan9252_pm.html
@@ -186,6 +186,31 @@
   var $ = function (id) { return document.getElementById(id); };
   var logBox = $("log");
 
+  /* DeviceLink 统一健康态（外壳 Owner 经 BroadcastChannel 广播）。
+     SPI 0xA2 失败 ≠ 设备离线：灯只认共享层；命令错误单独文案。 */
+  window.__pmSetConn = null;
+
+  function setConn(ok, text) {
+    var p = $("pillConn");
+    p.className = "pill " + (ok ? "online" : "offline");
+    $("pillConnTxt").textContent = text;
+  }
+  window.__pmSetConn = setConn;
+
+  /** SPI/业务失败：不得把「设备离线」打红（除非共享层已判离线）。 */
+  function setSpiFail(msg) {
+    log(msg, "err");
+    var dl = window.__pmDeviceLink;
+    var s = dl && dl.getSnapshot ? dl.getSnapshot() : null;
+    if (s && s.links && s.links.esp32 && s.links.esp32.online) {
+      setConn(true, "设备在线 · SPI 失败");
+    } else if (!s) {
+      /* 无外壳/尚未收到快照：退回旧语义 */
+      setConn(false, "连接失败 · 5s 后重试");
+    }
+    /* 有快照且 offline：留给 DeviceLink subscribe 刷新灯 */
+  }
+
   /* 与 js/common/base-url.js 同 key 同默认值：全局唯一设备 IP，不设独立连接区 */
   var LS_IP = "dcu_esp_ip", DEFAULT_IP = "192.168.31.127";
   function deviceIp() {
@@ -302,16 +327,15 @@
    * 事务本身会唤醒睡眠中的芯片，轮询等于不停叫醒它）；连败 3 次标红停轮。
    * pollGen：丢弃 enterMode/唤醒 之后仍在途的过期 1E 响应，避免竞态覆盖 UI。 ---- */
   var pollFail = 0, pollTimer = null, pollPaused = false, pollGen = 0;
-  function setConn(ok, text) {
-    var p = $("pillConn");
-    p.className = "pill " + (ok ? "online" : "offline");
-    $("pillConnTxt").textContent = text;
-  }
+  /** 主站看门狗豁免是否已置位（pmHold 幂等，防 2s 轮询刷屏） */
+  var pmHoldOn = false;
   function bumpPollGen() { return ++pollGen; }
   /* 仅在确认芯片已离开睡眠（唤醒成功 / 读到 SLEEP_EN=0 / NRST）时清 flag */
   function markAwake() {
     clearSleepFlag();
-    pmHold(0);   /* 芯片已醒：解除主站看门狗豁免，恢复正常自愈 */
+    /* 只在「之前置过豁免」时才解除：pollOnce 每 2s 调本函数，
+     * 无脑 pmHold(0) 会把「主站看门狗豁免解除」刷屏。 */
+    if (pmHoldOn) pmHold(0);
     $("sleepBanner").textContent =
       "🌙 芯片处于低功耗档 —— EtherCAT 通信已中断，点「手动唤醒」恢复";
   }
@@ -336,7 +360,7 @@
       if (gen !== pollGen || pollPaused) return;
       pollFail++;
       if (pollFail >= 3) {
-        setConn(false, "连接失败 · 5s 后重试");
+        setSpiFail("SPI 轮询失败 ×3（IP " + deviceIp() + "）· 5s 后重试");
         pollTimer = setTimeout(probe, 5000);
       } else {
         pollTimer = setTimeout(pollOnce, 2000);
@@ -359,8 +383,7 @@
         log("ESP32 可达: " + deviceIp() + "（未读 LAN9252，保持睡眠）", "ok");
       })
       .catch(function (e) {
-        setConn(false, "连接失败 · 5s 后重试");
-        log("连接失败: " + e.message + "（IP 取自 OTA 页的设备地址 " + deviceIp() + "）", "err");
+        setSpiFail("ESP32 探测失败: " + e.message + "（IP " + deviceIp() + "）");
         pollTimer = setTimeout(probeEspOnly, 5000);
       });
   }
@@ -374,8 +397,7 @@
         pollOnce();
       })
       .catch(function (e) {
-        setConn(false, "连接失败 · 5s 后重试");
-        log("连接失败: " + e.message + "（IP 取自 OTA 页的设备地址 " + deviceIp() + "）", "err");
+        setSpiFail("ESP32 探测失败: " + e.message + "（IP " + deviceIp() + "）");
         pollTimer = setTimeout(probe, 5000);
       });
   }
@@ -413,11 +435,14 @@
    * 即被偷偷拉回 OP——2026-09-12 实测休眠 ~20s 自动"复活"）。解除时主站
    * 自带 60s 冷却，让本页唤醒流程先走完。best-effort：native 未起只记日志。 */
   function pmHold(on) {
-    return ecatPost("pm/hold", { on: on }, 5000).then(function (r) {
-      log("主站看门狗豁免" + (on ? "置位" : "解除") +
+    var want = !!on;
+    if (pmHoldOn === want) return Promise.resolve();
+    return ecatPost("pm/hold", { on: want }, 5000).then(function (r) {
+      if (r.ok) pmHoldOn = want;
+      log("主站看门狗豁免" + (want ? "置位" : "解除") +
           (r.ok ? "" : "失败: " + r.log.join("；")), r.ok ? "ok" : "warn");
     }).catch(function (e) {
-      log("主站看门狗豁免" + (on ? "置位" : "解除") + "失败: " + e.message, "warn");
+      log("主站看门狗豁免" + (want ? "置位" : "解除") + "失败: " + e.message, "warn");
     });
   }
   function ecatEnsureOpen() {
@@ -425,8 +450,8 @@
     return ecatPost("native/health", {}, 6000).then(function (h) {
       var open = h.json && h.json.bus_open;
       if (open) return { ok: true, log: ["总线已 open"], json: h.json };
-      var adapter = "I210";
-      try { adapter = localStorage.getItem("dcu_ecat_adapter") || "I210"; } catch (e) {}
+      var adapter = (window.__pmDeviceLink && window.__pmDeviceLink.getEcatAdapter)
+        ? window.__pmDeviceLink.getEcatAdapter() : "I210";
       log("总线未 open，调用 /api/open (" + adapter + ") …");
       return ecatPost("open", { substr: adapter }, 20000);
     });
@@ -604,5 +629,14 @@
   }
 })();
 </script>
+<script type="module">
+  import { deviceLink } from '../js/common/device-link.js?v=20260916a';
+  window.__pmDeviceLink = deviceLink;
+  deviceLink.subscribe(function (s) {
+    if (!s || !s.links || !window.__pmSetConn) return;
+    var e = s.links.esp32;
+    window.__pmSetConn(!!e.online, e.online ? '已连接' : '离线');
+  });
+</script>
 </body>
 </html>
diff --git a/lab/spi_test.html b/lab/spi_test.html
index d784f75..96254e5 100644
--- a/lab/spi_test.html
+++ b/lab/spi_test.html
@@ -631,7 +631,7 @@ const spiOut = $("#out"), spiHist = $("#hist"), btnAbort = $("#btnAbort");
 const spiBtns = [$("#btnRun"), $("#btnRtt"), $("#btnStress")];
 let spiCtl = null;
 try { const saved = ls("spi_test_ip"); if (saved) $("#ip").value = saved; } catch (_) {}
-/* 设备 IP 与控制台其它页共用 dcu_esp_ip：其它页改过 IP，这里不必再手敲一遍 */
+/* 设备 IP 与 ConnectionHub / 其它页共用 dcu_esp_ip：其它页改过 IP，这里不必再手敲一遍 */
 if (!ls("spi_test_ip")) { const shared = ls("dcu_esp_ip"); if (shared) $("#ip").value = shared; }
 
 function spiBusy(busy, cls, text) {
diff --git a/scripts/test_ecat_dir_worktree.mjs b/scripts/test_ecat_dir_worktree.mjs
new file mode 100644
index 0000000..a4b5e1f
--- /dev/null
+++ b/scripts/test_ecat_dir_worktree.mjs
@@ -0,0 +1,57 @@
+/**
+ * 从 git worktree 启动 esp32_server 时，ECAT_DIR 必须指回主检出的
+ * tools/ecat，而不是 .../ESP32/.worktrees/ecat。
+ * 复刻 _resolve_ecat_dir 的纯路径逻辑（无 DOM/无网络）。
+ */
+import assert from "node:assert/strict";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+/** 与 esp32_server._resolve_ecat_dir 同构（JS 侧只测路径形状）。 */
+function resolveEcatDir(baseDir) {
+  let d = path.resolve(baseDir);
+  const parent = path.dirname(d);
+  if (path.basename(parent) === ".worktrees") {
+    d = path.dirname(parent);
+  }
+  return path.normalize(path.join(d, "..", "ecat"));
+}
+
+let failed = 0;
+function check(name, fn) {
+  try {
+    fn();
+    console.log("  ✓", name);
+  } catch (e) {
+    failed++;
+    console.log("  ✗", name, "—", e.message);
+  }
+}
+
+console.log("[worktree ECAT_DIR]");
+
+check("主检出 BASE_DIR → 兄弟 tools/ecat", () => {
+  const base = path.resolve("G:/Robot_v2/DCU/tools/ESP32");
+  const got = resolveEcatDir(base);
+  assert.equal(got, path.resolve("G:/Robot_v2/DCU/tools/ecat"), got);
+});
+
+check("worktree BASE_DIR → 仍指主检出的 tools/ecat", () => {
+  const base = path.resolve("G:/Robot_v2/DCU/tools/ESP32/.worktrees/device-link");
+  const got = resolveEcatDir(base);
+  assert.equal(got, path.resolve("G:/Robot_v2/DCU/tools/ecat"), got);
+});
+
+check("嵌套 slug 也走 .worktrees 父级", () => {
+  const base = path.resolve("G:/x/tools/ESP32/.worktrees/foo-bar");
+  const got = resolveEcatDir(base);
+  assert.equal(got, path.resolve("G:/x/tools/ecat"), got);
+});
+
+/* BASE_DIR 恒为 esp32_server.py 所在目录；普通主检出已在第一项覆盖。 */
+
+if (failed) {
+  console.log(`失败 ${failed} 项`);
+  process.exit(1);
+}
+console.log("通过 3 项，失败 0 项");
diff --git a/tabs.html b/tabs.html
index 254b5f3..bfb840e 100644
--- a/tabs.html
+++ b/tabs.html
@@ -179,5 +179,8 @@
 <!-- app 窗口租约: 本外壳窗口活着期间保持与本地服务的连接,
      全部窗口关闭后服务端自动停 EtherCAT PDO 循环(见 js/common/app-lease.js) -->
 <script src="js/common/app-lease.js"></script>
+<!-- DeviceLink Owner：全链路健康轮询只在本外壳跑一次，各 iframe 订阅 -->
+<script>window.__dcuDeviceLinkOwner = true;</script>
+<script type="module" src="js/common/device-link.js?v=20260916c"></script>
 </body>
 </html>