diff --git a/LD2453Parser.cpp b/LD2453Parser.cpp
index 177f87b..250b518 100644
--- a/LD2453Parser.cpp
+++ b/LD2453Parser.cpp
@@ -153,6 +153,21 @@ bool LD2453Parser::tryParseFrame() {
     // Frame hợp lệ! Parse data
     uint8_t *data = _ringBuffer + headerPos + HEADER_SIZE;
     
+    // Debug: dump toàn bộ data section nếu có byte nào khác 0
+    bool hasData = false;
+    for (size_t i = 0; i < DATA_SIZE; i++) {
+        if (data[i] != 0) { hasData = true; break; }
+    }
+    if (hasData && _rawDebug) {
+        Serial.print(F("[DATA SECTION] "));
+        for (size_t i = 0; i < DATA_SIZE; i++) {
+            if (data[i] < 0x10) Serial.print('0');
+            Serial.print(data[i], HEX);
+            Serial.print(' ');
+        }
+        Serial.println();
+    }
+    
     // Reset frame
     _lastFrame.timestamp_ms = millis();
     _lastFrame.sequence_number = ++_sequenceCounter;
@@ -163,18 +178,37 @@ bool LD2453Parser::tryParseFrame() {
     for (uint8_t t = 0; t < MAX_TARGETS; t++) {
         uint8_t *targetData = data + (t * TARGET_RECORD_SIZE);
         
-        // Byte layout (giả định, cần verify với manual):
+        if (hasData && _rawDebug) {
+            Serial.print(F("[SLOT "));
+            Serial.print(t + 1);
+            Serial.print(F("] "));
+            for (size_t i = 0; i < TARGET_RECORD_SIZE; i++) {
+                if (targetData[i] < 0x10) Serial.print('0');
+                Serial.print(targetData[i], HEX);
+                Serial.print(' ');
+            }
+            Serial.println();
+        }
+        
+        // Byte layout (v1 - giả định LD2450 style):
         // [0-1]: X (little endian, signed 16-bit, mm)
         // [2-3]: Y (little endian, signed 16-bit, mm)
         // [4-5]: Speed (little endian, signed 16-bit, cm/s)
-        // [6-7]: Reserved hoặc distance
+        // [6]:   Valid flag / target ID
+        // [7]:   Reserved
         
+        uint8_t validByte = targetData[6];
         int16_t x = (int16_t)(targetData[0] | (targetData[1] << 8));
         int16_t y = (int16_t)(targetData[2] | (targetData[3] << 8));
         int16_t speed = (int16_t)(targetData[4] | (targetData[5] << 8));
         
-        // Target valid nếu không phải tất cả đều 0
-        bool valid = (x != 0 || y != 0 || speed != 0);
+        // Target valid: có valid byte != 0 HOẶC có tọa độ/speed != 0
+        bool valid = (validByte != 0) || (x != 0 || y != 0 || speed != 0);
+        
+        // Nếu valid byte khác 0 nhưng tọa độ 0 thì vẫn valid (target đứng yên)
+        if (validByte != 0 && (x == 0 && y == 0 && speed == 0)) {
+            valid = false; // Không valid nếu có flag nhưng tọa độ 0
+        }
         
         _lastFrame.targets[t].valid = valid;
         _lastFrame.targets[t].x_mm = x;
@@ -182,10 +216,25 @@ bool LD2453Parser::tryParseFrame() {
         _lastFrame.targets[t].speed = speed;
         
         if (valid) {
-            // Tính distance và angle từ x, y
-            _lastFrame.targets[t].distance_mm = sqrt(x*x + y*y);
-            _lastFrame.targets[t].angle_deg = atan2(x, y) * 180.0 / PI;
+            if (x != 0 || y != 0) {
+                _lastFrame.targets[t].distance_mm = sqrt((float)x*x + (float)y*y);
+                _lastFrame.targets[t].angle_deg = atan2((float)x, (float)y) * 180.0 / PI;
+            } else {
+                _lastFrame.targets[t].distance_mm = 0;
+                _lastFrame.targets[t].angle_deg = 0;
+            }
             _lastFrame.targetCount++;
+            
+            if (_rawDebug) {
+                Serial.print(F("  -> Valid! X="));
+                Serial.print(x);
+                Serial.print(F(" Y="));
+                Serial.print(y);
+                Serial.print(F(" Speed="));
+                Serial.print(speed);
+                Serial.print(F(" ValidByte=0x"));
+                Serial.println(validByte, HEX);
+            }
         } else {
             _lastFrame.targets[t].distance_mm = 0;
             _lastFrame.targets[t].angle_deg = 0;
diff --git a/WebServerManager.cpp b/WebServerManager.cpp
index ef053ea..c744fb9 100644
--- a/WebServerManager.cpp
+++ b/WebServerManager.cpp
@@ -101,9 +101,12 @@ void WebServerManager::broadcastFrame(const RadarFrame &frame) {
     doc["node_id"] = frame.node_id;
     doc["sequence"] = frame.sequence_number;
     doc["timestamp"] = frame.timestamp_ms;
+    doc["target_count"] = frame.targetCount;
 
     JsonArray targets = doc["targets"].to<JsonArray>();
-    for (uint8_t i = 0; i < frame.targetCount && i < 3; i++) {
+    // Loop qua TẤT CẢ 3 slot, không chỉ dựa vào targetCount
+    // Đảm bảo target ở slot 2 vẫn được gửi ngay cả khi slot 1 trống
+    for (uint8_t i = 0; i < 3; i++) {
         const RadarTarget &t = frame.targets[i];
         JsonObject jt = targets.add<JsonObject>();
         jt["id"] = i + 1; // radar slot index, NOT a persistent person ID
@@ -111,6 +114,10 @@ void WebServerManager::broadcastFrame(const RadarFrame &frame) {
         jt["x"] = t.x_mm;
         jt["y"] = t.y_mm;
         jt["speed"] = t.speed;
+        if (t.valid) {
+            jt["distance"] = (int)t.distance_mm;
+            jt["angle"] = (int)t.angle_deg;
+        }
     }
 
     String out;