diff --git a/Resources.cpp b/Resources.cpp
index 73dd304..68aec5f 100644
--- a/Resources.cpp
+++ b/Resources.cpp
@@ -80,6 +80,8 @@ const String TEXT_RESOURCES[] = {
     "invalid frames:   ",
     "invalid checksum: ",
     "mbus address:     ",
+    "collisions:       ",
+    "r: ",
 
 };
 
diff --git a/Resources.h b/Resources.h
index 7f40f94..cb026e9 100644
--- a/Resources.h
+++ b/Resources.h
@@ -79,6 +79,8 @@ const uint8_t MBC_MYFRAMES_KEY = 63;
 const uint8_t MBC_INVALID_FRAMES_KEY = 64;
 const uint8_t MBC_INVALID_CHECKSUM_CNT_KEY = 65;
 const uint8_t MBC_ADDRESS_LONG_KEY = 66;
+const uint8_t MBC_COLLISION_CNT_KEY = 67;
+const uint8_t R_KEY = 68;
 
 
 const String& getResource(uint8_t key);
diff --git a/ThermometerPro.cpp b/ThermometerPro.cpp
index 5bf8866..b08c53a 100644
--- a/ThermometerPro.cpp
+++ b/ThermometerPro.cpp
@@ -8,6 +8,7 @@
 #include "meterBusClient.h"
 
 
+const unsigned char OK_LED_PIN = 2;
 
 static CmdServer cmdServer(&Serial);
 static ConfigInvalidateCmd configInvalidateCmd;
@@ -16,6 +17,9 @@ static Thermometer thermometer;
 static MeterBusClient meterBusClient;
 
 void setup() {
+  pinMode(OK_LED_PIN, OUTPUT);
+  digitalWrite(OK_LED_PIN, LOW);
+
   Serial.begin(9600);
 
   Config::initialize();
@@ -28,6 +32,8 @@ void setup() {
   uptime.begin(&cmdServer);
   thermometer.begin(&cmdServer);
   meterBusClient.begin(&cmdServer, &thermometer);
+
+  digitalWrite(OK_LED_PIN, HIGH);
 }
 
 
diff --git a/meterBusClient.cpp b/meterBusClient.cpp
index cca01f2..883f8a4 100644
--- a/meterBusClient.cpp
+++ b/meterBusClient.cpp
@@ -37,6 +37,7 @@ String MeterBusClientConfig::exec(String params) {
     Serial.print(getResource(MBC_MYFRAMES_KEY)); Serial.print(m_meterBusClient->m_myFrameCnt); Serial.println();
     Serial.print(getResource(MBC_INVALID_FRAMES_KEY)); Serial.print(m_meterBusClient->m_invalidFrameCnt); Serial.println();
     Serial.print(getResource(MBC_INVALID_CHECKSUM_CNT_KEY)); Serial.print(m_meterBusClient->m_invalidChecksum); Serial.println();
+    Serial.print(getResource(MBC_COLLISION_CNT_KEY)); Serial.print(m_meterBusClient->m_collisionCnt); Serial.println();
     Serial.print(getResource(MBC_ADDRESS_LONG_KEY)); Serial.print(m_meterBusClient->getAddress()); Serial.println();
   } else {
     res = "subcommand not found";
@@ -49,7 +50,8 @@ String MeterBusClientConfig::exec(String params) {
 
 
 MeterBusClient::MeterBusClient() : m_meterBusClientConfig(this), m_address(0),
-    m_frameCnt(0), m_myFrameCnt(0), m_invalidFrameCnt(0), m_invalidChecksum(0) {
+    m_frameCnt(0), m_myFrameCnt(0), m_invalidFrameCnt(0), m_invalidChecksum(0),
+    m_collisionCnt(0) {
 
 }
 
@@ -59,7 +61,11 @@ void MeterBusClient::begin(CmdServer *cmdServer, Thermometer *thermometer) {
   m_meterBusClientConfig.registerYourself(cmdServer);
   m_thermometer = thermometer;
 
-  Serial3.begin(1200);
+  //Serial3.begin(1200);
+  //Serial3.begin(2400, SERIAL_8E1);
+  Serial3.begin(2400);
+  UART2_C1 |= UART_C1_PE | UART_C1_M;
+
 
 
   setAddress(Config::getUChar(Config::METERBUSCLIENT_ADDRESS));
@@ -147,7 +153,8 @@ bool isChecksumValid(MeterBusFrame frame) {
 
 
 
-void MeterBusClient::handleFrame() {
+bool MeterBusClient::handleFrame() {
+  bool res = false;
   m_frameCnt++;
   if (! isChecksumValid(m_frame)) {
     Serial.println(getResource(MBC_INVALID_CHECKSUM_KEY));
@@ -176,19 +183,22 @@ void MeterBusClient::handleFrame() {
     if (m_frame.startDelimiter == 0x10) {
       if (m_frame.cField == 0x40)  {
         SND_NKE();
+        res = true;
       } else if (m_frame.cField == 0x5b) {
         REQ_UD2();
+        res = true;
       } else {
         Serial.println(getResource(MBC_UNHANDLED_FRAME_KEY));
       }
     }
   }
+  return res;
 }
 
 
 typedef enum {
   STATE_START, STATE_IDLE, STATE_SHORT_FRAME, STATE_LONG_CTRL_FRAME, STATE_HANDLE, STATE_INVALID, STATE_DONE,
-  STATE_DELAYED_HANDLE, STATE_DELAY
+  STATE_DELAYED_RESPONSE, STATE_DELAY, STATE_RESPONSE, STATE_RECEIVE_ECHO
 } e_meterBusClientState;
 
 typedef enum {
@@ -201,9 +211,13 @@ void MeterBusClient::exec() {
   static e_meterBusClientState state = STATE_IDLE;
   static e_meterBusClientSubState subState = SUBSTATE_LENGTH;
   static unsigned char userDataCnt = 0;
+  static unsigned int echoReceiveCnt = 0;
   static unsigned long receivedDoneTimestamp;
 
   int chi = Serial3.read();
+  if (chi != -1) {
+    Serial.print("Received: "); Serial.println(chi, 16);
+  }
   char ch = (char) chi;
 
   switch (state) {
@@ -312,28 +326,48 @@ void MeterBusClient::exec() {
     break;
 
   case STATE_INVALID:
+    Serial.println("INVALID FRAME");
     m_invalidFrameCnt++;
     state = STATE_START;
     break;
 
   case STATE_HANDLE:
-    state = STATE_DELAY;
-    receivedDoneTimestamp = millis();
+    state = STATE_DONE;
+    if (m_frame.valid) {
+      receivedDoneTimestamp = millis();
+      if (handleFrame()) {
+        state = STATE_DELAY;
+      }
+    }
     break;
 
   case STATE_DELAY:
     if ((receivedDoneTimestamp + RESPONSE_DELAY) < millis()) {
-      state = STATE_DELAYED_HANDLE;
+      state = STATE_DELAYED_RESPONSE;
     }
     break;
 
-  case STATE_DELAYED_HANDLE:
-    if (m_frame.valid) {
-      handleFrame();
-    } else {
-      Serial.println(getResource(MBC_NO_VALID_FRAME_KEY));
+  case STATE_DELAYED_RESPONSE:
+    for (unsigned int i = 0; i < sendBufferLen; i++) {
+      Serial3.write(sendBuffer[i]);
+    }
+    echoReceiveCnt = 0;
+    state = STATE_RECEIVE_ECHO;
+    break;
+
+  case STATE_RECEIVE_ECHO:
+    if (chi != -1) {
+      Serial.println("echo character");
+      if (ch == sendBuffer[echoReceiveCnt]) {
+        echoReceiveCnt++;
+        if (echoReceiveCnt == sendBufferLen) {
+          state = STATE_DONE;
+        }
+      } else {
+        m_collisionCnt++;
+        state = STATE_DONE;
+      }
     }
-    state = STATE_DONE;
     break;
 
   case STATE_DONE:
diff --git a/meterBusClient.h b/meterBusClient.h
index 2e092a6..1ad2b22 100644
--- a/meterBusClient.h
+++ b/meterBusClient.h
@@ -80,13 +80,19 @@ private:
   unsigned char m_address;
   void setAddress(unsigned char address);
   unsigned char getAddress();
-  void handleFrame();
+  bool handleFrame();
   MeterBusFrame m_frame;
 
+  unsigned char sendBuffer[265];
+  unsigned int sendBufferLen;
+  void aSB(unsigned char c); // append to send buffer
+  unsigned char calcSendChecksum();
+
   unsigned long m_frameCnt;
   unsigned long m_myFrameCnt;
   unsigned long m_invalidFrameCnt;
   unsigned long m_invalidChecksum;
+  unsigned long m_collisionCnt;
 
   bool m_debug;
   bool getDebug();
diff --git a/meterBusClientFrames.cpp b/meterBusClientFrames.cpp
index e1f021c..90dc0c1 100644
--- a/meterBusClientFrames.cpp
+++ b/meterBusClientFrames.cpp
@@ -7,13 +7,34 @@
 
 #include "meterBusClient.h"
 
+inline void MeterBusClient::aSB(unsigned char c) {
+  sendBuffer[sendBufferLen++] = c;
+}
+
+unsigned char MeterBusClient::calcSendChecksum() {
+  unsigned char checksum = 0;
+  for (unsigned int i = 4; i < sendBufferLen; i++) {
+    checksum += sendBuffer[i];
+  }
+  return checksum;
+}
 
 void MeterBusClient::SND_NKE() {
-  Serial3.write(0xE5);
+  sendBufferLen = 0;
+  aSB(0xE5);
 }
 
 void MeterBusClient::REQ_UD2() {
-
+  sendBufferLen = 0;
+  aSB(0x68);
+  aSB(0x03);
+  aSB(0x03);
+  aSB(0x68);
+  aSB(0x01);
+  aSB(getAddress());
+  aSB(0x03);
+  aSB(calcSendChecksum());
+  aSB(0x16);
 }
 
 
diff --git a/thermometer.cpp b/thermometer.cpp
index 4b77571..7f6c538 100644
--- a/thermometer.cpp
+++ b/thermometer.cpp
@@ -63,6 +63,7 @@ String ThermValues::exec(String params) {
   for (unsigned int i = 0; i < NUM_OF_CHANNELS; i++) {
     m_stream->print(getResource(INDEX_KEY)); m_stream->print(i); m_stream->print(getResource(COMMA_SPACE_KEY));
     m_stream->print(getResource(CAL_KEY)); m_stream->print(m_thermometer->getCalibrateFactor(i), 6); m_stream->print(getResource(COMMA_SPACE_KEY));
+    m_stream->print(getResource(R_KEY)); m_stream->print(m_thermometer->m_r[i], 6); m_stream->print(getResource(COMMA_SPACE_KEY));
     m_stream->print(getResource(T_KEY)); m_stream->print(m_thermometer->m_temperature[i], 6); m_stream->print(getResource(COMMA_SPACE_KEY));
     m_stream->print(getResource(TS_KEY)); m_stream->print(m_thermometer->m_smoothedTemperature[i], 6);
     m_stream->println();
@@ -354,6 +355,7 @@ void Thermometer::exec() {
         if (COMPILE_TIME_DEBUG && getDebug()) { Serial.print("calibrateFactor="); Serial.print(getCalibrateFactor(i), 6); Serial.print(getResource(COMMA_SPACE_KEY)); }
         float r = (((float)(m_n[i] - ((i == 3) ? 0 : m_n[i + 1]))) / ((float)N_MAX)) * R_REF * getCalibrateFactor(i);
         if (COMPILE_TIME_DEBUG && getDebug()) { Serial.print("r="); Serial.print(r); Serial.print(getResource(COMMA_SPACE_KEY)); }
+        m_r[i] = r;
         float t = pt1000(r);
         if (COMPILE_TIME_DEBUG && getDebug()) { Serial.print("t="); Serial.print(t); Serial.print(getResource(COMMA_SPACE_KEY)); }
         if (COMPILE_TIME_DEBUG && getDebug()) { Serial.println(); }
diff --git a/thermometer.h b/thermometer.h
index 3878e8c..f551afd 100644
--- a/thermometer.h
+++ b/thermometer.h
@@ -85,6 +85,7 @@ private:
 
   unsigned long m_n[NUM_OF_CHANNELS];
   float m_calibrateFactor[NUM_OF_CHANNELS];
+  float m_r[NUM_OF_CHANNELS];
   float m_temperature[NUM_OF_CHANNELS];
   float m_lastSmoothedTemperature[NUM_OF_CHANNELS];
   float m_smoothedTemperature[NUM_OF_CHANNELS];