diff --git a/usart.c b/usart.c
index c0f0687..b6aaf01 100644
--- a/usart.c
+++ b/usart.c
@@ -3,6 +3,7 @@
 #include "usart.h"
 #include "conf.h"
 #include "ringbuffer.h"
+#include <avr/interrupt.h>
 
 volatile ringbuffer_t usart_buffer;
 
@@ -11,16 +12,26 @@ void
 usart_init(void)
 {
 	usart_buffer = ringbuffer_new(USART_BUFFER_SIZE);
-	UBRRH = (unsigned char)(UBRR_VALUE >> 8);
-	UBRRL = (unsigned char)UBRR_VALUE;
-	UCSRB = _BV(TXEN) | _BV(TXCIE);
-	UCSRC = _BV(USBS) | _BV(UCSZ0) | _BV(UCSZ1);
+	UBRR0H = (unsigned char)(UBRR_VALUE >> 8);
+	UBRR0L = (unsigned char)UBRR_VALUE;
+	UCSR0B = _BV(TXEN0) | _BV(TXCIE0);
+	UCSR0C = _BV(UCSZ00) | _BV(UCSZ01);
+	sei();
 }
 
 int
 usart_putc(char c)
 {
-	return ringbuffer_put_char(usart_buffer, c);
+	int result = ringbuffer_put_char(usart_buffer, c);
+	// If the buffer is already emtpy there is no
+	// need to wait for the interrupt.
+	// Also it is likely that the interrupt will never happen.
+	// (For instance because this is the first byte sent)
+	if(UCSR0A & _BV(UDRE0))
+	{
+		UDR0 = ringbuffer_get_char(usart_buffer);
+	}
+	return result;
 }
 	
 
@@ -29,7 +40,7 @@ ISR(USART_TX_vect)
 {
 	if(ringbuffer_nonempty(usart_buffer))
 	{
-		while(!(UCSRA & UDRE));
-		UDR = ringbuffer_get_char(usart_buffer);
+		UDR0 = ringbuffer_get_char(usart_buffer);
+		UCSR0A |= _BV(TXC0);
 	}
 }