diff --git a/.vscode/settings.json b/.vscode/settings.json
new file mode 100644
index 00000000..9ddf6b28
--- /dev/null
+++ b/.vscode/settings.json
@@ -0,0 +1,3 @@
+{
+    "cmake.ignoreCMakeListsMissing": true
+}
\ No newline at end of file
diff --git a/src/BLEAdvertisingData.cpp b/src/BLEAdvertisingData.cpp
index 80105916..4f21139c 100644
--- a/src/BLEAdvertisingData.cpp
+++ b/src/BLEAdvertisingData.cpp
@@ -20,6 +20,7 @@
 #include "BLEAdvertisingData.h"
 
 #define AD_FIELD_OVERHEAD (2)
+#define AD_NAME_LENGTH (19)
 
 BLEAdvertisingData::BLEAdvertisingData() :
   _dataLength(0),
@@ -29,6 +30,11 @@ BLEAdvertisingData::BLEAdvertisingData() :
   _flags(0),
   _hasFlags(false),
   _localName(NULL),
+  _minimumConnectionInterval(0),
+  _maximumConnectionInterval(0),
+  _hasConnectionInterval(false),
+  _TransmitPowerLevel(0),
+  _hasTransmitPowerLevel(false),
   _manufacturerData(NULL),
   _manufacturerDataLength(0),
   _manufacturerCompanyId(0),
@@ -73,6 +79,11 @@ void BLEAdvertisingData::clear()
   _rawDataLength = 0;
   _hasFlags = false;
   _localName = NULL;
+  _minimumConnectionInterval = 0;
+  _maximumConnectionInterval = 0;
+  _hasConnectionInterval = false;
+  _TransmitPowerLevel = 0;
+  _hasTransmitPowerLevel = false;
   _manufacturerData = NULL;
   _manufacturerDataLength = 0;
   _hasManufacturerCompanyId = false;
@@ -90,6 +101,11 @@ void BLEAdvertisingData::copy(const BLEAdvertisingData& adv)
   _flags = adv._flags;
   _hasFlags = adv._hasFlags;
   _localName = adv._localName;
+  _minimumConnectionInterval = adv._minimumConnectionInterval;
+  _maximumConnectionInterval = adv._maximumConnectionInterval;
+  _hasConnectionInterval = adv._hasConnectionInterval;
+  _TransmitPowerLevel = adv._TransmitPowerLevel;
+  _hasTransmitPowerLevel = adv._hasTransmitPowerLevel;
   _manufacturerData = adv._manufacturerData;
   _manufacturerDataLength = adv._manufacturerDataLength;
   _manufacturerCompanyId = adv._manufacturerCompanyId;
@@ -183,6 +199,29 @@ bool BLEAdvertisingData::setLocalName(const char *localName)
   return success;
 }
 
+bool BLEAdvertisingData::setAdvertisedConnectionInterval(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval)
+{
+  int previousLength = (_hasConnectionInterval) ? ( sizeof(_minimumConnectionInterval) + sizeof(_maximumConnectionInterval) + AD_FIELD_OVERHEAD) : 0;
+  bool success = updateRemainingLength(previousLength, (sizeof(minimumConnectionInterval) + sizeof(maximumConnectionInterval) + AD_FIELD_OVERHEAD));
+  if (success) {
+    _hasConnectionInterval = true;
+    _minimumConnectionInterval = minimumConnectionInterval;
+    _maximumConnectionInterval = maximumConnectionInterval;
+  }
+  return success;
+}
+
+bool BLEAdvertisingData::setAdvertisedTransmitPowerLevel(uint8_t TransmitPowerLevel)
+{
+  int previousLength = (_hasTransmitPowerLevel) ? ( sizeof(_TransmitPowerLevel) + AD_FIELD_OVERHEAD) : 0;
+  bool success = updateRemainingLength(previousLength, (sizeof(TransmitPowerLevel) + AD_FIELD_OVERHEAD));
+  if (success) {
+    _hasTransmitPowerLevel = true;
+    _TransmitPowerLevel = TransmitPowerLevel;
+  }
+  return success;
+}
+
 bool BLEAdvertisingData::setRawData(const uint8_t* data, int length)
 {
   if (length > MAX_AD_DATA_LENGTH) {
@@ -248,6 +287,14 @@ bool BLEAdvertisingData::updateData()
   if (_localName) {
     success &= addLocalName(_localName);
   }
+  // Try to add Slave Connection Interval into the current advertising packet
+  if (_hasConnectionInterval) {
+    success &= addAdvertisedConnectionInterval(_minimumConnectionInterval, _maximumConnectionInterval);
+  }
+  // Try to add Transmit Power Level into the current advertising packet
+  if (_hasTransmitPowerLevel) {
+    success &= addAdvertisedTransmitPowerLevel(_TransmitPowerLevel);
+  }
   return success;
 }
 
@@ -272,7 +319,11 @@ bool BLEAdvertisingData::addLocalName(const char *localName)
   if (strlen(localName) > (MAX_AD_DATA_LENGTH - AD_FIELD_OVERHEAD)) {
     success = addField(BLEFieldShortLocalName, (uint8_t*)localName, (MAX_AD_DATA_LENGTH - AD_FIELD_OVERHEAD));
   } else {
-    success = addField(BLEFieldCompleteLocalName, localName);
+    uint8_t tempData[AD_NAME_LENGTH];
+    uint8_t tempDataLength = strlen(localName);
+    memcpy(tempData, (uint8_t*)localName, tempDataLength + 1);
+    memset(&tempData[tempDataLength + 1], 0x20, AD_NAME_LENGTH - tempDataLength - 1);
+    success = addField(BLEFieldCompleteLocalName, tempData, AD_NAME_LENGTH);
   }
   return success;
 }
@@ -330,6 +381,19 @@ bool BLEAdvertisingData::addFlags(uint8_t flags)
   return addField(BLEFieldFlags, &flags, sizeof(flags));
 }
 
+bool BLEAdvertisingData::addAdvertisedConnectionInterval(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval)
+{
+  uint8_t tempData[sizeof(minimumConnectionInterval) + sizeof(maximumConnectionInterval)];
+  memcpy(tempData, &minimumConnectionInterval, sizeof(minimumConnectionInterval));
+  memcpy(&tempData[sizeof(minimumConnectionInterval)], &maximumConnectionInterval, sizeof(maximumConnectionInterval));
+  return addField(BLEFieldConnectionInterval, tempData, sizeof(minimumConnectionInterval) + sizeof(maximumConnectionInterval));
+}
+
+bool BLEAdvertisingData::addAdvertisedTransmitPowerLevel(uint8_t TransmitPowerLevel)
+{
+  return addField(BLEFieldTransmitPowerLevel, &TransmitPowerLevel, sizeof(TransmitPowerLevel));
+}
+
 bool BLEAdvertisingData::addField(BLEAdField field, const char* data)
 {
   int dataLength = strlen(data);
diff --git a/src/BLEAdvertisingData.h b/src/BLEAdvertisingData.h
index dc736053..9f11a85f 100644
--- a/src/BLEAdvertisingData.h
+++ b/src/BLEAdvertisingData.h
@@ -40,6 +40,8 @@ enum BLEAdField {
   BLEFieldCompleteAdvertisedService128 = 0x07,
   BLEFieldShortLocalName = 0x08,
   BLEFieldCompleteLocalName = 0x09,
+  BLEFieldTransmitPowerLevel = 0x0A,
+  BLEFieldConnectionInterval = 0x12,
   BLEFieldServiceData = 0x16,
   BLEFieldManufacturerData = 0xFF,
 
@@ -66,6 +68,8 @@ class BLEAdvertisingData {
   bool setManufacturerData(const uint8_t manufacturerData[], int manufacturerDataLength);
   bool setManufacturerData(const uint16_t companyId, const uint8_t manufacturerData[], int manufacturerDataLength);
   bool setLocalName(const char *localName);
+  bool setAdvertisedConnectionInterval(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval);
+  bool setAdvertisedTransmitPowerLevel(uint8_t TransmitPowerLevel);
   bool setAdvertisedServiceData(uint16_t uuid, const uint8_t data[], int length);
   bool setRawData(const uint8_t* data, int length);
   bool setRawData(const BLEAdvertisingRawData& data);
@@ -86,6 +90,8 @@ class BLEAdvertisingData {
   bool addManufacturerData(const uint8_t manufacturerData[], int manufacturerDataLength);
   bool addManufacturerData(const uint16_t companyId, const uint8_t manufacturerData[], int manufacturerDataLength);
   bool addLocalName(const char *localName);
+  bool addAdvertisedConnectionInterval(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval);
+  bool addAdvertisedTransmitPowerLevel(uint8_t TransmitPowerLevel);
   bool addAdvertisedServiceData(uint16_t uuid, const uint8_t data[], int length);
   bool addRawData(const uint8_t* data, int length);
   bool addFlags(uint8_t flags);
@@ -105,6 +111,12 @@ class BLEAdvertisingData {
   bool _hasFlags;
   const char* _localName;
 
+  uint16_t _minimumConnectionInterval;
+  uint16_t _maximumConnectionInterval;
+  bool _hasConnectionInterval;
+  uint8_t _TransmitPowerLevel;
+  bool _hasTransmitPowerLevel;
+
   const uint8_t* _manufacturerData;
   int _manufacturerDataLength;
   uint16_t _manufacturerCompanyId;
diff --git a/src/BLEProperty.h b/src/BLEProperty.h
index b9238ba9..0735e6a9 100644
--- a/src/BLEProperty.h
+++ b/src/BLEProperty.h
@@ -75,5 +75,9 @@ enum BLE_GATT_PERM_ {
   WRITE_AUTHORIZATION = 1 << 10,
 };
 
+#define   GAP_PPCP_MIN_CONN_INTERVAL           (80)       /* 100 ms  */
+#define   GAP_PPCP_MAX_CONN_INTERVAL           (160)      /* 200 ms  */
+#define   GAP_PPCP_SLAVE_LATENCY               (0)        /* 0 ms    */
+#define   GAP_PPCP_SUPERVISION_TMO             (1000)     /* 1000 ms */
 
 #endif
diff --git a/src/local/BLELocalCharacteristic.cpp b/src/local/BLELocalCharacteristic.cpp
index dc8a819d..f7a7b732 100644
--- a/src/local/BLELocalCharacteristic.cpp
+++ b/src/local/BLELocalCharacteristic.cpp
@@ -221,7 +221,17 @@ void BLELocalCharacteristic::writeValue(BLEDevice device, const uint8_t value[],
 {
   _written = true;
 
+  if (_properties & BLEWriteWithoutResponse) {
+    _valueLength = min(length, _valueSize);
+    memcpy(_value, value, _valueLength);
+
+    if (_fixedLength) {
+      _valueLength = _valueSize;
+    }
+  } 
+  else {
   writeValue(value, length);
+  }
 
   if (_eventHandlers[BLEWritten]) {
     _eventHandlers[BLEWritten](device, BLECharacteristic(this));
diff --git a/src/local/BLELocalDevice.cpp b/src/local/BLELocalDevice.cpp
index 89c7a580..abac9b5a 100644
--- a/src/local/BLELocalDevice.cpp
+++ b/src/local/BLELocalDevice.cpp
@@ -354,6 +354,11 @@ void BLELocalDevice::setAppearance(uint16_t appearance)
   GATT.setAppearance(appearance);
 }
 
+void BLELocalDevice::setPreferredConnectionParameters(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval, uint16_t slaveLatency, uint16_t connectionSupervisionTimeout)
+{
+  GATT.setPreferredConnectionParameters(minimumConnectionInterval, maximumConnectionInterval, slaveLatency, connectionSupervisionTimeout);
+}
+
 void BLELocalDevice::addService(BLEService& service)
 {
   GATT.addService(service);
diff --git a/src/local/BLELocalDevice.h b/src/local/BLELocalDevice.h
index 6c45c063..2d880e28 100644
--- a/src/local/BLELocalDevice.h
+++ b/src/local/BLELocalDevice.h
@@ -60,6 +60,7 @@ class BLELocalDevice {
 
   virtual void setDeviceName(const char* deviceName);
   virtual void setAppearance(uint16_t appearance);
+  virtual void setPreferredConnectionParameters(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval, uint16_t slaveLatency, uint16_t connectionSupervisionTimeout);
 
   virtual void addService(BLEService& service);
 
diff --git a/src/utility/GATT.cpp b/src/utility/GATT.cpp
index 3550fd99..467b5b2e 100644
--- a/src/utility/GATT.cpp
+++ b/src/utility/GATT.cpp
@@ -31,8 +31,9 @@ GATTClass::GATTClass() :
   _genericAccessService(NULL),
   _deviceNameCharacteristic(NULL),
   _appearanceCharacteristic(NULL),
-  _genericAttributeService(NULL),
-  _servicesChangedCharacteristic(NULL)
+  _preferredConnectionParametersCharacteristic(NULL),
+  _genericAttributeService(NULL)
+//_servicesChangedCharacteristic(NULL)
 {
 }
 
@@ -46,21 +47,25 @@ void GATTClass::begin()
   _genericAccessService = new BLELocalService("1800");
   _deviceNameCharacteristic = new BLELocalCharacteristic("2a00", BLERead, 20);
   _appearanceCharacteristic = new BLELocalCharacteristic("2a01", BLERead, 2);
+  _preferredConnectionParametersCharacteristic = new BLELocalCharacteristic("2a04", BLERead, 8);
   _genericAttributeService = new BLELocalService("1801");
-  _servicesChangedCharacteristic = new BLELocalCharacteristic("2a05", BLEIndicate, 4);
+//_servicesChangedCharacteristic = new BLELocalCharacteristic("2a05", BLEIndicate, 4);
 
   _genericAccessService->retain();
   _deviceNameCharacteristic->retain();
   _appearanceCharacteristic->retain();
+  _preferredConnectionParametersCharacteristic->retain();
   _genericAttributeService->retain();
-  _servicesChangedCharacteristic->retain();
+//_servicesChangedCharacteristic->retain();
 
   _genericAccessService->addCharacteristic(_deviceNameCharacteristic);
   _genericAccessService->addCharacteristic(_appearanceCharacteristic);
-  _genericAttributeService->addCharacteristic(_servicesChangedCharacteristic);
+  _genericAccessService->addCharacteristic(_preferredConnectionParametersCharacteristic);
+//_genericAttributeService->addCharacteristic(_servicesChangedCharacteristic);
 
   setDeviceName("Arduino");
   setAppearance(0x000);
+  setPreferredConnectionParameters(GAP_PPCP_MIN_CONN_INTERVAL, GAP_PPCP_MAX_CONN_INTERVAL, GAP_PPCP_SLAVE_LATENCY, GAP_PPCP_SUPERVISION_TMO);
 
   clearAttributes();
 
@@ -85,16 +90,21 @@ void GATTClass::end()
     _appearanceCharacteristic = NULL;
   }
 
+  if (_preferredConnectionParametersCharacteristic &&_preferredConnectionParametersCharacteristic->release() == 0) {
+    delete(_preferredConnectionParametersCharacteristic);
+    _preferredConnectionParametersCharacteristic = NULL;
+  }
+  
   if (_genericAttributeService && _genericAttributeService->release() == 0) {
     delete(_genericAttributeService);
     _genericAttributeService = NULL;
   }
-
+/*
   if (_servicesChangedCharacteristic && _servicesChangedCharacteristic->release() == 0) {
-    delete(_servicesChangedCharacteristic);
-    _servicesChangedCharacteristic = NULL;
+     delete(_servicesChangedCharacteristic);
+     _servicesChangedCharacteristic = NULL;
   }
-
+*/
   clearAttributes();
 }
 
@@ -108,6 +118,12 @@ void GATTClass::setAppearance(uint16_t appearance)
   _appearanceCharacteristic->writeValue((uint8_t*)&appearance, sizeof(appearance));
 }
 
+void GATTClass::setPreferredConnectionParameters(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval, uint16_t slaveLatency, uint16_t connectionSupervisionTimeout)
+{
+  uint16_t PPCPData[] = {minimumConnectionInterval, maximumConnectionInterval, slaveLatency, connectionSupervisionTimeout};
+  _preferredConnectionParametersCharacteristic->writeValue((uint8_t*)&PPCPData, sizeof(PPCPData));
+}
+
 void GATTClass::addService(BLEService& service)
 {
   BLELocalService* localService = service.local();
diff --git a/src/utility/GATT.h b/src/utility/GATT.h
index 51d1537e..c8e2f86e 100644
--- a/src/utility/GATT.h
+++ b/src/utility/GATT.h
@@ -38,6 +38,7 @@ class GATTClass {
 
   virtual void setDeviceName(const char* deviceName);
   virtual void setAppearance(uint16_t appearance);
+  virtual void setPreferredConnectionParameters(uint16_t minimumConnectionInterval, uint16_t maximumConnectionInterval, uint16_t slaveLatency, uint16_t connectionSupervisionTimeout);
 
   virtual void addService(BLEService& service);
 
@@ -64,8 +65,9 @@ class GATTClass {
   BLELocalService*              _genericAccessService;
   BLELocalCharacteristic*       _deviceNameCharacteristic;
   BLELocalCharacteristic*       _appearanceCharacteristic;
+  BLELocalCharacteristic*       _preferredConnectionParametersCharacteristic;
   BLELocalService*              _genericAttributeService;
-  BLELocalCharacteristic*       _servicesChangedCharacteristic;
+//BLELocalCharacteristic*       _servicesChangedCharacteristic;
 };
 
 extern GATTClass& GATT;