diff --git a/src/knx/tpuart_data_link_layer.cpp b/src/knx/tpuart_data_link_layer.cpp
index 4c5c39b0..c7dffdd3 100644
--- a/src/knx/tpuart_data_link_layer.cpp
+++ b/src/knx/tpuart_data_link_layer.cpp
@@ -525,6 +525,7 @@ void TpUartDataLinkLayer::processRxFrameComplete(uint8_t debug)
         print(debug);
         print(" - ");
         print(_platform.uartAvailable());
+        print(" - ");
         printHex(" - Invalid frame: ", _rxFrame->data(), _rxFrame->size(), false);
         print("\x1B[");
         print(0);
diff --git a/src/rp2040_arduino_platform.cpp b/src/rp2040_arduino_platform.cpp
index 97d0be01..cb0eda5b 100644
--- a/src/rp2040_arduino_platform.cpp
+++ b/src/rp2040_arduino_platform.cpp
@@ -37,21 +37,24 @@ For usage of KNX-IP you have to define either
 #include <hardware/watchdog.h> // from Pico SDK
 #include <pico/unique_id.h>    // from Pico SDK
 
-#ifdef KNX_USE_DMA_UART0
+#ifdef USE_KNX_DMA_UART
 #include <hardware/dma.h>
-constexpr uint32_t uartDmaTransferCount = 0b1111111111;
-// constexpr uint32_t uartDmaTransferCount = UINT32_MAX;
+// constexpr uint32_t uartDmaTransferCount = 0b1111111111;
+constexpr uint32_t uartDmaTransferCount = UINT32_MAX;
 constexpr uint8_t uartDmaBufferExp = 8u; // 2**BufferExp
 constexpr uint16_t uartDmaBufferSize = (1u << uartDmaBufferExp);
 int8_t uartDmaChannel = -1;
 volatile uint8_t __attribute__((aligned(uartDmaBufferSize))) uartDmaBuffer[uartDmaBufferSize] = {};
 volatile uint32_t uartDmaReadCount = 0;
 volatile uint16_t uartDmaRestartCount = 0;
+volatile uint32_t uartDmaWriteCount2 = 0;
+volatile uint32_t uartDmaAvail = 0;
 
 // Liefert die Zahl der gelesenen Bytes seit dem DMA Transferstart
 inline uint32_t uartDmaWriteCount()
 {
-    return uartDmaTransferCount - dma_channel_hw_addr(uartDmaChannel)->transfer_count;
+    uartDmaWriteCount2 = uartDmaTransferCount - dma_channel_hw_addr(uartDmaChannel)->transfer_count;
+    return uartDmaWriteCount2;
 }
 
 // Liefert die aktuelle Schreibposition im DMA Buffer
@@ -111,18 +114,16 @@ extern Wiznet5500lwIP KNX_NETIF;
 #endif
 
 RP2040ArduinoPlatform::RP2040ArduinoPlatform()
-#if !defined(KNX_NO_DEFAULT_UART) && !defined(KNX_USE_DMA_UART0)
+#if !defined(KNX_NO_DEFAULT_UART) && !defined(USE_KNX_DMA_UART)
     : ArduinoPlatform(&KNX_SERIAL)
 #endif
 {
-#ifndef KNX_USE_DMA_UART0
 #ifdef KNX_UART_RX_PIN
     _rxPin = KNX_UART_RX_PIN;
 #endif
 #ifdef KNX_UART_TX_PIN
     _txPin = KNX_UART_TX_PIN;
 #endif
-#endif
 #ifndef USE_RP2040_EEPROM_EMULATION
     _memoryType = Flash;
 #endif
@@ -138,15 +139,13 @@ RP2040ArduinoPlatform::RP2040ArduinoPlatform(HardwareSerial* s)
 
 void RP2040ArduinoPlatform::knxUartPins(pin_size_t rxPin, pin_size_t txPin)
 {
-#ifdef KNX_USE_DMA_UART0
     _rxPin = rxPin;
     _txPin = txPin;
-#endif
 }
 
 bool RP2040ArduinoPlatform::overflowUart()
 {
-#ifdef KNX_USE_DMA_UART0
+#ifdef USE_KNX_DMA_UART
     // during dma restart
     bool ret;
     const uint32_t writeCount = uartDmaWriteCount();
@@ -176,16 +175,19 @@ bool RP2040ArduinoPlatform::overflowUart()
 
 void RP2040ArduinoPlatform::setupUart()
 {
-#ifdef KNX_USE_DMA_UART0
+#ifdef USE_KNX_DMA_UART
     if (uartDmaChannel == -1)
     {
         // configure uart0
-        gpio_set_function(0, GPIO_FUNC_UART);
-        gpio_set_function(1, GPIO_FUNC_UART);
-        uart_init(uart0, 19200);
-        uart_set_hw_flow(uart0, false, false);
-        uart_set_format(uart0, 8, 1, UART_PARITY_EVEN);
-        uart_set_fifo_enabled(uart0, false);
+        println("----------------");
+        println(_rxPin);
+        println(_txPin);
+        gpio_set_function(_rxPin, GPIO_FUNC_UART);
+        gpio_set_function(_txPin, GPIO_FUNC_UART);
+        uart_init(KNX_DMA_UART, 19200);
+        uart_set_hw_flow(KNX_DMA_UART, false, false);
+        uart_set_format(KNX_DMA_UART, 8, 1, UART_PARITY_EVEN);
+        uart_set_fifo_enabled(KNX_DMA_UART, false);
 
         // configure uart0
         uartDmaChannel = dma_claim_unused_channel(true); // get free channel for dma
@@ -195,7 +197,7 @@ void RP2040ArduinoPlatform::setupUart()
         channel_config_set_write_increment(&dmaConfig, true);
         channel_config_set_high_priority(&dmaConfig, true);
         channel_config_set_ring(&dmaConfig, true, uartDmaBufferExp);
-        channel_config_set_dreq(&dmaConfig, DREQ_UART0_RX);
+        channel_config_set_dreq(&dmaConfig, KNX_DMA_UART_DREQ);
         dma_channel_set_read_addr(uartDmaChannel, &uart_get_hw(uart0)->dr, false);
         dma_channel_set_write_addr(uartDmaChannel, uartDmaBuffer, false);
         dma_channel_set_trans_count(uartDmaChannel, uartDmaTransferCount, false);
@@ -222,7 +224,7 @@ void RP2040ArduinoPlatform::setupUart()
 #endif
 }
 
-#ifdef KNX_USE_DMA_UART0
+#ifdef USE_KNX_DMA_UART
 int RP2040ArduinoPlatform::uartAvailable()
 {
     if (uartDmaChannel == -1)
@@ -235,7 +237,8 @@ int RP2040ArduinoPlatform::uartAvailable()
     else
     {
         uint32_t tc = dma_channel_hw_addr(uartDmaChannel)->transfer_count;
-        int test = uartDmaTransferCount - (tc)-uartDmaReadCount;
+        uartDmaAvail = tc;
+        int test = uartDmaTransferCount - tc - uartDmaReadCount;
         if (test < -1)
         {
             println("FATAL");
diff --git a/src/rp2040_arduino_platform.h b/src/rp2040_arduino_platform.h
index 27b4695a..264d1b80 100644
--- a/src/rp2040_arduino_platform.h
+++ b/src/rp2040_arduino_platform.h
@@ -58,6 +58,16 @@
 
 #endif
 
+#if USE_KNX_DMA_UART == 0
+#define KNX_DMA_UART uart0
+#define KNX_DMA_UART_IRQ UART0_IRQ
+#define KNX_DMA_UART_DREQ DREQ_UART0_RX
+#elif USE_KNX_DMA_UART == 1
+#define KNX_DMA_UART uart1
+#define KNX_DMA_UART_IRQ UART1_IRQ
+#define KNX_DMA_UART_DREQ DREQ_UART1_RX
+#endif
+
 
 class RP2040ArduinoPlatform : public ArduinoPlatform
 {
@@ -69,7 +79,7 @@ class RP2040ArduinoPlatform : public ArduinoPlatform
     void knxUartPins(pin_size_t rxPin, pin_size_t txPin);
     void setupUart() override;
     bool overflowUart() override;
-    #ifdef KNX_USE_DMA_UART0
+    #ifdef USE_KNX_DMA_UART
     int uartAvailable() override;
     void closeUart() override;
     void knxUart( HardwareSerial* serial) override {};