diff --git a/src/knx/platform.cpp b/src/knx/platform.cpp
index fa6906c..e71c35a 100644
--- a/src/knx/platform.cpp
+++ b/src/knx/platform.cpp
@@ -133,6 +133,12 @@ size_t Platform::getNonVolatileMemorySize()
 
 void Platform::commitNonVolatileMemory()
 {
+    if(_bufferedEraseblockNumber > -1 && _bufferedEraseblockDirty)
+    {
+        writeBufferedEraseBlock(_bufferedEraseblockNumber);
+        
+        // _bufferedEraseblockNumber = -1;  // does that make sense?
+    }
 }
 
 uint32_t Platform::writeNonVolatileMemory(uint32_t relativeAddress, uint8_t* buffer, size_t size)
@@ -172,26 +178,39 @@ void Platform::loadEraseblockContaining(uint32_t relativeAddress)
 
 uint32_t Platform::bufferedEraseBlockStart()
 {
-    return  _bufferedEraseblockNumber * flashEraseBlockSize();
+    return  _bufferedEraseblockNumber * (flashEraseBlockSize() * flashPageSize());
 }
 
 uint32_t Platform::bufferedEraseBlockEnd()
 {
-    return (_bufferedEraseblockNumber + 1) * flashEraseBlockSize() -1;
+    return (_bufferedEraseblockNumber + 1) * (flashEraseBlockSize() * flashPageSize()) -1;
 }
 
 
 int32_t Platform::getEraseBlockNumberOf(uint32_t relativeAddress)
 {
-    return -1;
+    return relativeAddress / (flashEraseBlockSize() * flashPageSize());
 }
 
 
 void Platform::writeBufferedEraseBlock()
 {
+    if(_bufferedEraseblockNumber > -1 && _bufferedEraseblockDirty)
+    {
+        flashErase(_bufferedEraseblockNumber);
+        for(int i = 0; i< ; i++)
+        {   // ToDo
+            flashWritePage();
+        }
+        _bufferedEraseblockDirty = false;
+    }
 }
 
 
 void Platform::bufferEraseBlock(uint32_t eraseBlockNumber)
 {
+    memcpy(_eraseblockBuffer, userFlashStart() + eraseBlockNumber * flashEraseBlockSize() * flashPageSize(), flashEraseBlockSize() * flashPageSize());
+
+    _bufferedEraseblockNumber = eraseBlockNumber;
+    _bufferedEraseblockDirty = false;
 }
diff --git a/src/knx/platform.h b/src/knx/platform.h
index e32e1f6..05616b6 100644
--- a/src/knx/platform.h
+++ b/src/knx/platform.h
@@ -59,9 +59,12 @@ class Platform
   protected:
         // Flash memory
     
-    virtual size_t flashEraseBlockSize(); // in pages
-    virtual size_t flashPageSize();       // in bytes
-    virtual uint8_t* userFlashStart();   // start of user flash aligned to start of an erase block
+    // size of one EraseBlock in pages
+    virtual size_t flashEraseBlockSize();
+    // size of one flash page in bytes
+    virtual size_t flashPageSize();
+    // start of user flash aligned to start of an erase block
+    virtual uint8_t* userFlashStart();
     virtual size_t userFlashSizeEraseBlocks(); // in eraseBlocks
     virtual void flashErase(uint16_t eraseBlockNum); //relativ to userFlashStart
     virtual void flashWritePage(uint16_t pageNumber, uint8_t* data); //write a single page to flash (pageNumber relative to userFashStart
@@ -73,7 +76,9 @@ class Platform
     uint32_t bufferedEraseBlockStart();
     uint32_t bufferedEraseBlockEnd();
     int32_t getEraseBlockNumberOf(uint32_t relativeAddress);
+    // writes _eraseblockBuffer to flash
     void writeBufferedEraseBlock();
+    // copies a EraseBlock into the _eraseblockBuffer
     void bufferEraseBlock(uint32_t eraseBlockNumber);
 
     // in theory we would have to use this buffer for memory reads too,
diff --git a/src/rp2040_arduino_platform.cpp b/src/rp2040_arduino_platform.cpp
index 72341f5..392a9de 100644
--- a/src/rp2040_arduino_platform.cpp
+++ b/src/rp2040_arduino_platform.cpp
@@ -16,7 +16,7 @@ For more, use or own emulation (maybe with littlefs)
 #include "rp2040_arduino_platform.h"
 
 #ifdef ARDUINO_ARCH_RP2040
-#include <knx/bits.h>
+#include "knx/bits.h"
 
 #include <Arduino.h>
 
@@ -24,6 +24,7 @@ For more, use or own emulation (maybe with littlefs)
 #include <EEPROM.h>             // EEPROM emulation in flash, part of Earl E Philhowers Pi Pico Arduino support 
 #include <pico/unique_id.h>     // from Pico SDK
 #include <hardware/watchdog.h>  // from Pico SDK
+#include <hardware/flash.h>     // from Pico SDK
 
 
 RP2040ArduinoPlatform::RP2040ArduinoPlatform()
@@ -77,6 +78,56 @@ void RP2040ArduinoPlatform::commitToEeprom()
 {
     EEPROM.commit();
 }
+
+
+size_t RP2040ArduinoPlatform::flashEraseBlockSize()
+{
+    return 16; // 16 pages x 256byte/page = 4096byte
+}
+
+size_t RP2040ArduinoPlatform::flashPageSize()
+{
+    return 256;
+}
+
+uint8_t* RP2040ArduinoPlatform::userFlashStart()
+{
+    // TODO
+    // XIP_BASE + KNX_FLASH_OFFSET
+    return nullptr;
+}
+
+size_t RP2040ArduinoPlatform::userFlashSizeEraseBlocks()
+{
+    if(KNX_FLASH_SIZE <= 0)
+        return 0;
+    else
+        return ( (KNX_FLASH_SIZE - 1) / (flashPageSize() * flashEraseBlockSize())) + 1;
+}
+
+void RP2040ArduinoPlatform::flashErase(uint16_t eraseBlockNum)
+{
+    noInterrupts();
+    rp2040.idleOtherCore();
+
+    // TODO: calculate position in flash
+    flash_range_erase (0x100, flashPageSize() * flashEraseBlockSize());
+
+    rp2040.resumeOtherCore();
+    interrupts();
+}
+
+void RP2040ArduinoPlatform::flashWritePage(uint16_t pageNumber, uint8_t* data)
+{
+    noInterrupts();
+    rp2040.idleOtherCore();
+
+    // TODO: calculate position in flash
+    flash_range_program(0x100, data, flashPageSize());
+
+    rp2040.resumeOtherCore();
+    interrupts();
+}
 #endif
 
 
diff --git a/src/rp2040_arduino_platform.h b/src/rp2040_arduino_platform.h
index 3077b21..1b19451 100644
--- a/src/rp2040_arduino_platform.h
+++ b/src/rp2040_arduino_platform.h
@@ -4,6 +4,14 @@
 
 #ifdef ARDUINO_ARCH_RP2040
 
+#ifndef KNX_FLASH_OFFSET
+#define KNX_FLASH_OFFSET 0x180000   // 1.5MiB
+#endif
+
+#ifndef KNX_FLASH_SIZE
+#define KNX_FLASH_SIZE 1024
+#endif
+
 class RP2040ArduinoPlatform : public ArduinoPlatform
 {
 public:
@@ -11,11 +19,20 @@ public:
     RP2040ArduinoPlatform( HardwareSerial* s);
 
     // unique serial number
-    uint32_t uniqueSerialNumber() override;
+    uint32_t uniqueSerialNumber(); //override; 
 
     void restart();
     uint8_t* getEepromBuffer(uint16_t size);
     void commitToEeprom();
+
+
+
+    size_t flashEraseBlockSize(); // in bytes
+    size_t flashPageSize();       // in bytes
+    uint8_t* userFlashStart();   // start of user flash aligned to start of an erase block
+    size_t userFlashSizeEraseBlocks(); // in eraseBlocks
+    void flashErase(uint16_t eraseBlockNum); //relativ to userFlashStart
+    void flashWritePage(uint16_t pageNumber, uint8_t* data); //write a single page to flash (pageNumber relative to userFashStart
 };
 
 #endif