diff --git a/ECTrainer2/BitalMonitor.cpp b/ECTrainer2/BitalMonitor.cpp
index 8eaf4df..f794815 100644
--- a/ECTrainer2/BitalMonitor.cpp
+++ b/ECTrainer2/BitalMonitor.cpp
@@ -41,7 +41,7 @@
 	char comBuf[256] = { '\0' };
 	char valueStr[10] = { '\0' };
 
-	int count = 0;
+	DWORD lastRR = 0;	// �O���RR�擾���ԁi�^�C���A�E�g�� 0�j
 	while (_pEct->IsAppRun()) {
 
 		// �o�C�^��
@@ -61,8 +61,9 @@
 						int RR = atoi(sp + 1);
 						if (RR > 0) {
 							_rrInterval.Put(RR);
+							lastRR = timeGetTime();
 						}
-						std::cout << "Read:" << RR << std::endl;
+						//std::cout << "Read:" << RR << std::endl;
 					}
 					sp = pt + 1;
 				}
@@ -72,8 +73,14 @@
 
 			//std::cout << "lastBuf2:" << lastBuf << std::endl;
 		}
+
+		// ���M�����o
+		if (lastRR > 0 && timeGetTime() - lastRR > NO_SIGNAL_TIMEOUT) {
+			_rrInterval.Put(0);
+			lastRR = 0;
+		}
+
 		Sleep(10);
-		//if (++count > 20) break;
 	}
 
 	return true;
diff --git a/ECTrainer2/BitalMonitor.h b/ECTrainer2/BitalMonitor.h
index c9507d4..842dbe9 100644
--- a/ECTrainer2/BitalMonitor.h
+++ b/ECTrainer2/BitalMonitor.h
@@ -9,6 +9,7 @@
 {
 	const int COM_PORT = 4;
 	const char LF = 10;
+	const int NO_SIGNAL_TIMEOUT = 5000; // ���M���Ɣ��肷�鎞�� (ms)
 
 	GComPort _Com;
 	RingBuffer<int> _rrInterval;