diff --git a/js/ble/gatt.js b/js/ble/gatt.js
index 45ad39a..25282e9 100644
--- a/js/ble/gatt.js
+++ b/js/ble/gatt.js
@@ -105,19 +105,21 @@ export async function connectBle() {
 
     setBleStage(2, '已就绪', null);
     setConnectionState(true);
-    try { deviceLink.reportBle(true, device.name || ''); } catch (_) {}
     bleLog('BLE', 'GATT 服务与特征获取完成');
     await enableNotifications();
     // ★ 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);
diff --git a/js/common/connection.js b/js/common/connection.js
index 41899f9..5b7d2d5 100644
--- a/js/common/connection.js
+++ b/js/common/connection.js
@@ -61,8 +61,9 @@ export function updateConnectionUi(connected, text) {
   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;
-      text = connected ? '已连接' : '离线';
+      if (!text) text = connected ? '已连接' : '离线';
     }
   } catch (_) {}
   var label = text || (connected ? '已连接' : '未连接');
diff --git a/js/common/device-link.js b/js/common/device-link.js
index 9cdb3d8..c7ca260 100644
--- a/js/common/device-link.js
+++ b/js/common/device-link.js
@@ -68,8 +68,6 @@ function createOwner() {
     if (ch) {
       try { ch.postMessage({ type: "snapshot", snap: snap }); } catch (_) {}
     }
-    /* 同源 iframe 也可读 window 顶层缓存（BC 不可用时的弱备份） */
-    try { window.__dcuDeviceLinkSnap = snap; } catch (_) {}
   }
 
   function setEsp32(status, ok) {
@@ -133,15 +131,17 @@ function createOwner() {
       e.online = !!(st && st.ok && st.slave);
       e.busOpen = e.online;
       /* native status 不直接给 op/loop；用 load valid + slave state 粗判 */
-      e.op = !!(st && st.slave && (st.slave.state & 0x0F) === 8);
+      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;
       publish();
+    }).catch(function () {
+      /* 字段访问/异常不得让 ECAT 轮询永久停摆 */
     }).then(function () {
-      ecatTimer = setTimeout(pollEcat, ECAT_POLL_MS);
+      if (!stopped) ecatTimer = setTimeout(pollEcat, ECAT_POLL_MS);
     });
   }
 
@@ -190,7 +190,6 @@ function createClient() {
   try { ch = new BroadcastChannel(CH_NAME); } catch (_) { ch = null; }
   var listeners = [];
   var last = null;
-  try { last = window.__dcuDeviceLinkSnap || null; } catch (_) {}
 
   function emit() {
     for (var i = 0; i < listeners.length; i++) {
@@ -203,7 +202,6 @@ function createClient() {
       var m = ev && ev.data;
       if (!m || m.type !== "snapshot" || !m.snap) return;
       last = m.snap;
-      try { window.__dcuDeviceLinkSnap = last; } catch (_) {}
       emit();
     });
     try { ch.postMessage({ type: "hello" }); } catch (_) {}