diff --git a/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt b/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
index 53e1865..1d71c6c 100644
--- a/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
+++ b/app/src/main/java/com/example/medilightv2android/ble/BleManager.kt
@@ -1199,10 +1199,6 @@ class BleManager private constructor(private val context: Context) {
                 val state = if (data.size >= 5) data[4].toInt() and 0xFF else -1
                 debugLogger.rx("rls", data.size, "led_state=$state")
             }
-            "rxs:" -> {
-                val echoCmd = if (data.size > 4) String(data, 4, minOf(data.size - 4, 10), Charsets.US_ASCII).trim() else "?"
-                debugLogger.rx("rxs", data.size, "cmd_not_supported: $echoCmd")
-            }
             "rbb:" -> {
                 debugLogger.rx("rbb", data.size, "full measurement header (battery+IMU+temp)")
                 onMbbHeaderReceived?.invoke(data)
@@ -1212,9 +1208,15 @@ class BleManager private constructor(private val context: Context) {
                 // msp 명령 응답 — IMU 데이터. format 불명확이라 defensive parsing.
                 val hex = data.take(kotlin.math.min(data.size, 24)).joinToString(" ") { "%02X".format(it) }
                 debugLogger.rx("rsp", data.size, "IMU data hex=$hex")
+                android.util.Log.d("ImuDbg", "rsp RX len=${data.size} hex=$hex")
                 imuCollector.parseRsp(data)
                 onImuReceived?.invoke(data)
             }
+            "rxs:" -> {
+                val echoCmd = if (data.size > 4) String(data, 4, minOf(data.size - 4, 10), Charsets.US_ASCII).trim() else "?"
+                android.util.Log.w("ImuDbg", "rxs cmd_not_supported: $echoCmd")
+                debugLogger.rx("rxs", data.size, "cmd_not_supported: $echoCmd")
+            }
             "rim:" -> {
                 val num = if (data.size >= 6) ((data[4].toInt() and 0xFF) shl 8) or (data[5].toInt() and 0xFF) else 0
                 debugLogger.rx("rim", data.size, "IMU ${num} samples")
diff --git a/app/src/main/java/com/example/medilightv2android/ui/views/monitoring/PiezoMonitoringView.kt b/app/src/main/java/com/example/medilightv2android/ui/views/monitoring/PiezoMonitoringView.kt
index 90afb32..c54118c 100644
--- a/app/src/main/java/com/example/medilightv2android/ui/views/monitoring/PiezoMonitoringView.kt
+++ b/app/src/main/java/com/example/medilightv2android/ui/views/monitoring/PiezoMonitoringView.kt
@@ -591,24 +591,29 @@ fun PiezoMonitoringView(appState: AppState) {
         }
     }
 
-    // IMU polling + 자세 분류 (Phase 1) — 5초 주기로 msp 명령 → rim: 응답 받아 분류.
-    // monitoring 페이지 머무는 동안만 작동. demo 모드는 fake 자세 (toggle 없이 SUPINE).
+    // IMU polling + 자세 분류 (Phase 1) — 5초 주기로 msp 명령 → rsp: 응답 받아 분류.
     LaunchedEffect(isConnected, isDemoMode) {
+        Log.d("ImuDbg", "LaunchedEffect start isConnected=$isConnected isDemoMode=$isDemoMode")
         if (isDemoMode) {
             currentPosture = com.example.medilightv2android.managers.Posture.SUPINE
             return@LaunchedEffect
         }
         bleManager.imuCollector.onComplete = { samples ->
             val r = com.example.medilightv2android.managers.ImuPostureClassifier.classify(samples)
-            // UNKNOWN 이면 직전 posture 유지 (motion artifact 시 잠깐 흔들림 방지)
             if (r.posture != com.example.medilightv2android.managers.Posture.UNKNOWN) {
                 currentPosture = r.posture
             }
-            Log.d("PiezoMonitor", "POSTURE ${r.posture} pitch=${"%.1f".format(r.pitchDeg)}° accMag=${"%.2f".format(r.accMag)}g gyro=${"%.1f".format(r.gyroMagDps)}dps (${r.reason})")
+            Log.d("ImuDbg", "POSTURE ${r.posture} pitch=${"%.1f".format(r.pitchDeg)}° accMag=${"%.2f".format(r.accMag)}g gyro=${"%.1f".format(r.gyroMagDps)}dps (${r.reason}) samples=${samples.size}")
+        }
+        bleManager.imuCollector.onLog = { msg ->
+            Log.d("ImuDbg", "imuCollector log: $msg")
         }
         while (isActive) {
             if (isConnected) {
+                Log.d("ImuDbg", "→ sendImuQuery (msp)")
                 bleManager.sendImuQuery()
+            } else {
+                Log.d("ImuDbg", "skip (not connected)")
             }
             kotlinx.coroutines.delay(5000)
         }