diff --git a/src/knx/bau07B0.cpp b/src/knx/bau07B0.cpp
index 87db8ce..6d5b464 100644
--- a/src/knx/bau07B0.cpp
+++ b/src/knx/bau07B0.cpp
@@ -15,6 +15,11 @@ Bau07B0::Bau07B0(Platform& platform)
     uint16_t maskVersion;
     popWord(maskVersion, _descriptor);
     _deviceObj.maskVersion(maskVersion);
+
+    // Set which interface objects are available in the device object
+    // This differs from BAU to BAU with different medium types.
+    // See PID_IO_LIST
+    _deviceObj.ifObj(_ifObjs);
 }
 
 InterfaceObject* Bau07B0::getInterfaceObject(uint8_t idx)
diff --git a/src/knx/bau07B0.h b/src/knx/bau07B0.h
index 84d8aba..5fe3f67 100644
--- a/src/knx/bau07B0.h
+++ b/src/knx/bau07B0.h
@@ -16,4 +16,6 @@ class Bau07B0 : public BauSystemB
   private:
     TpUartDataLinkLayer _dlLayer;
     uint8_t _descriptor[2] = {0x07, 0xb0};
+    const uint32_t _ifObjs[6] = { 5, // length
+                                  OT_DEVICE, OT_ADDR_TABLE, OT_ASSOC_TABLE, OT_GRP_OBJ_TABLE, OT_APPLICATION_PROG};
 };
\ No newline at end of file
diff --git a/src/knx/bau27B0.cpp b/src/knx/bau27B0.cpp
index 2b5365d..f704eb5 100644
--- a/src/knx/bau27B0.cpp
+++ b/src/knx/bau27B0.cpp
@@ -16,6 +16,18 @@ Bau27B0::Bau27B0(Platform& platform)
     uint16_t maskVersion;
     popWord(maskVersion, _descriptor);
     _deviceObj.maskVersion(maskVersion);
+
+    // Set the maximum APDU length
+    // ETS will consider this value while programming the device
+    // For KNX-RF we use a smallest allowed value for now,
+    // although long frame are also supported by the implementation.
+    // Needs some experimentation.
+    _deviceObj.maxApduLength(15);
+
+    // Set which interface objects are available in the device object
+    // This differs from BAU to BAU with different medium types.
+    // See PID_IO_LIST
+    _deviceObj.ifObj(_ifObjs);
 }
 
 // see KNX AN160 p.74 for mask 27B0
diff --git a/src/knx/bau27B0.h b/src/knx/bau27B0.h
index f1b30e6..b2c129e 100644
--- a/src/knx/bau27B0.h
+++ b/src/knx/bau27B0.h
@@ -20,6 +20,8 @@ class Bau27B0 : public BauSystemB
     RfMediumObject _rfMediumObj;
 
     uint8_t _descriptor[2] = {0x27, 0xB0};
+    const uint32_t _ifObjs[7] = { 6, // length
+                                  OT_DEVICE, OT_ADDR_TABLE, OT_ASSOC_TABLE, OT_GRP_OBJ_TABLE, OT_APPLICATION_PROG, OT_RF_MEDIUM};
 
     void domainAddressSerialNumberWriteIndication(Priority priority, HopCountType hopType, uint8_t* rfDoA,
                                                   uint8_t* knxSerialNumber);
diff --git a/src/knx/bau57B0.cpp b/src/knx/bau57B0.cpp
index 74373c9..648d777 100644
--- a/src/knx/bau57B0.cpp
+++ b/src/knx/bau57B0.cpp
@@ -17,6 +17,11 @@ Bau57B0::Bau57B0(Platform& platform)
     uint16_t maskVersion;
     popWord(maskVersion, _descriptor);
     _deviceObj.maskVersion(maskVersion);
+
+    // Set which interface objects are available in the device object
+    // This differs from BAU to BAU with different medium types.
+    // See PID_IO_LIST
+    _deviceObj.ifObj(_ifObjs);
 }
 
 InterfaceObject* Bau57B0::getInterfaceObject(uint8_t idx)
diff --git a/src/knx/bau57B0.h b/src/knx/bau57B0.h
index 297f4aa..8835150 100644
--- a/src/knx/bau57B0.h
+++ b/src/knx/bau57B0.h
@@ -18,4 +18,6 @@ class Bau57B0 : public BauSystemB
     IpParameterObject _ipParameters;
     IpDataLinkLayer _dlLayer;
     uint8_t _descriptor[2] = {0x57, 0xb0};
+    const uint32_t _ifObjs[7] = { 6, // length
+                                  OT_DEVICE, OT_ADDR_TABLE, OT_ASSOC_TABLE, OT_GRP_OBJ_TABLE, OT_APPLICATION_PROG, OT_IP_PARAMETER};
 };
\ No newline at end of file
diff --git a/src/knx/device_object.cpp b/src/knx/device_object.cpp
index f7a5f85..e9d0905 100644
--- a/src/knx/device_object.cpp
+++ b/src/knx/device_object.cpp
@@ -35,7 +35,7 @@ void DeviceObject::readProperty(PropertyID propertyId, uint32_t start, uint32_t&
             *data = _prgMode;
             break;
         case PID_MAX_APDU_LENGTH:
-            pushWord(254, data);
+            pushWord(_maxApduLength, data);
             break;
         case PID_SUBNET_ADDR:
             *data = ((_ownAddress >> 8) & 0xff);
@@ -45,13 +45,8 @@ void DeviceObject::readProperty(PropertyID propertyId, uint32_t start, uint32_t&
             break;
         case PID_IO_LIST:
         {
-            uint32_t ifObjs[] = {
-                6, // length
-                OT_DEVICE, OT_ADDR_TABLE, OT_ASSOC_TABLE, OT_GRP_OBJ_TABLE, OT_APPLICATION_PROG, OT_IP_PARAMETER};
-
-            for (uint32_t i = start; i < (ifObjs[0] + 1) && i < count; i++)
-                pushInt(ifObjs[i], data);
-
+            for (uint32_t i = start; i < (_ifObjs[0] + 1) && i < count; i++)
+                pushInt(_ifObjs[i], data);
             break;
         }
         case PID_DEVICE_DESCRIPTOR:
@@ -263,6 +258,26 @@ void DeviceObject::maskVersion(uint16_t value)
     _maskVersion = value;
 }
 
+void DeviceObject::maxApduLength(uint16_t value)
+{
+    _maxApduLength = value;
+}
+
+uint16_t DeviceObject::maxApduLength()
+{
+    return _maxApduLength;
+}
+
+const uint32_t* DeviceObject::ifObj()
+{
+    return _ifObjs;
+}
+
+void DeviceObject::ifObj(const uint32_t* value)
+{
+    _ifObjs = value;
+}
+
 static PropertyDescription _propertyDescriptions[] = 
 {
     { PID_OBJECT_TYPE, false, PDT_UNSIGNED_INT, 1, ReadLv3 | WriteLv0 },
diff --git a/src/knx/device_object.h b/src/knx/device_object.h
index de86bb5..2f01665 100644
--- a/src/knx/device_object.h
+++ b/src/knx/device_object.h
@@ -37,6 +37,10 @@ public:
     void version(uint16_t value);
     uint16_t maskVersion();
     void maskVersion(uint16_t value);
+    uint16_t maxApduLength();
+    void maxApduLength(uint16_t value);
+    const uint32_t* ifObj();
+    void ifObj(const uint32_t* value);
 protected:
     uint8_t propertyCount();
     PropertyDescription* propertyDescriptions();
@@ -51,4 +55,6 @@ private:
     uint8_t _hardwareType[6] = { 0, 0, 0, 0, 0, 0};
     uint16_t _version = 0;
     uint16_t _maskVersion = 0x0000;
+    uint16_t _maxApduLength = 254;
+    const uint32_t* _ifObjs;
 };
\ No newline at end of file