diff --git a/src/uart.c b/src/uart.c
index 00b903f..fc0143d 100644
--- a/src/uart.c
+++ b/src/uart.c
@@ -1,105 +1,109 @@
-#include <avr/io.h>
-#include <avr/interrupt.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <util/delay.h>
-
-#include "uart.h"
-#include "fifo.h"
-
-#define UART_BUFSIZE_IN      16
-#define UART_BUFSIZE_OUT     64
-
-uint8_t uart_inbuf[UART_BUFSIZE_IN];
-uint8_t uart_outbuf[UART_BUFSIZE_OUT];
-
-fifo_t uart_infifo;
-fifo_t uart_outfifo;
-
-void
-UART_Init (void)
-{
-  // Save Status Register and disable Interrupts
-  uint8_t sreg = SREG;
-  cli();
-  
-  // Set Baudrate according to datasheet (16MHz -> 9600 Baud -> 103)
-  UBRR0 = 103;
-  
-  // Enable RX, TX and RX Complete Interrupt
-  UCSR0B = (1 << RXEN0)|(1 << TXEN0)|(1 << RXCIE0);
-  
-  // Reset Complete-Flags
-  UCSR0A = (1 << RXC0)|(1 << TXC0);
-  
-  // Reset Status Register
-  SREG = sreg;
-  
-  // Initialize FIFO Buffers
-  fifo_init(&uart_infifo, uart_inbuf, UART_BUFSIZE_IN);
-  fifo_init(&uart_outfifo, uart_outbuf, UART_BUFSIZE_OUT);
-}
-
-int8_t
-UART_PutChar (const uint8_t c)
-{
-
-
-  
-  // Put char into TX Buffer
-  int8_t ret = fifo_put(&uart_outfifo, c);
-
-  // Enable DRE Interrupt
-  UCSR0B |= (1 << UDRIE0);
-   
-  return ret;
-}
-
-// Receive Interrupt Routine
-ISR(USART0_RX_vect)
-{
-  fifo_put(&uart_infifo, UDR0);
-}
-
-// Data Register Empty Interrupt
-ISR(USART0_UDRE_vect)
-{
-  if (uart_outfifo.count > 0)
-    UDR0 = fifo_get_nowait(&uart_outfifo);
-  else
-    UCSR0B &= ~(1 << UDRIE0);
-}
-
-int16_t
-UART_GetChar (void)
-{
-  return fifo_get_nowait(&uart_infifo);
-}
-
-uint8_t
-UART_GetChar_Wait (void)
-{
-  return fifo_get_wait(&uart_infifo);
-}
-
-void
-UART_PutString (const char *s)
-{
-  do
-    {
-      UART_PutChar(*s);
-    }
-  while (*(s++));
-}
-
-void
-UART_PutInteger (const int i)
-{
-  // Buffer for Output
-  char buffer[10];
-  
-  // Convert Integer to ASCII, Base 10
-  itoa(i, buffer, 10);
-  
-  UART_PutString(buffer);
-}
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <util/delay.h>
+
+#include "uart.h"
+#include "fifo.h"
+
+#define UART_BUFSIZE_IN      16
+#define UART_BUFSIZE_OUT     64
+
+uint8_t uart_inbuf[UART_BUFSIZE_IN];
+uint8_t uart_outbuf[UART_BUFSIZE_OUT];
+
+fifo_t uart_infifo;
+fifo_t uart_outfifo;
+
+void
+UART_Init (void)
+{
+  // Save Status Register and disable Interrupts
+  uint8_t sreg = SREG;
+  cli();
+  
+  // Set Baudrate according to datasheet (16MHz -> 9600 Baud -> 103)
+  UBRR0 = 103;
+  
+  // Enable RX, TX and RX Complete Interrupt
+  UCSR0B = (1 << RXEN0)|(1 << TXEN0)|(1 << RXCIE0);
+  
+  // Reset Complete-Flags
+  UCSR0A = (1 << RXC0)|(1 << TXC0);
+  
+  // Reset Status Register
+  SREG = sreg;
+  
+  // Initialize FIFO Buffers
+  fifo_init(&uart_infifo, uart_inbuf, UART_BUFSIZE_IN);
+  fifo_init(&uart_outfifo, uart_outbuf, UART_BUFSIZE_OUT);
+}
+
+int8_t
+UART_PutChar (const uint8_t c)
+{
+
+
+  
+  // Put char into TX Buffer
+  int8_t ret = fifo_put(&uart_outfifo, c);
+
+  // Enable DRE Interrupt
+  UCSR0B |= (1 << UDRIE0);
+   
+  return ret;
+}
+
+#ifndef GDBSTUB
+
+// Receive Interrupt Routine
+ISR(USART0_RX_vect)
+{
+  fifo_put(&uart_infifo, UDR0);
+}
+
+// Data Register Empty Interrupt
+ISR(USART0_UDRE_vect)
+{
+  if (uart_outfifo.count > 0)
+    UDR0 = fifo_get_nowait(&uart_outfifo);
+  else
+    UCSR0B &= ~(1 << UDRIE0);
+}
+
+#endif
+
+int16_t
+UART_GetChar (void)
+{
+  return fifo_get_nowait(&uart_infifo);
+}
+
+uint8_t
+UART_GetChar_Wait (void)
+{
+  return fifo_get_wait(&uart_infifo);
+}
+
+void
+UART_PutString (const char *s)
+{
+  do
+    {
+      UART_PutChar(*s);
+    }
+  while (*(s++));
+}
+
+void
+UART_PutInteger (const int i)
+{
+  // Buffer for Output
+  char buffer[10];
+  
+  // Convert Integer to ASCII, Base 10
+  itoa(i, buffer, 10);
+  
+  UART_PutString(buffer);
+}