#include <avr/io.h> 
#include <inttypes.h> 
#include <util/delay.h> 
#include <avr/interrupt.h> 
#include <string.h>
#include "RS485.h" 
#define TAKT 8000000UL 	// Frequenz
#define TEILER  (TAKT/(16UL*BAUD))-1

void Uart_Init()
{	
   	// Baudrate Einstellung
	//UBRR0L = (TAKT/(16UL*BAUD))-1;	//Baudrate
	UBRR0H = (unsigned char) (TEILER>>8); 
    	UBRR0L = (unsigned char) TEILER; 
	
	//Sender und Empfänger ein
	UCSR0B |= (1<<TXEN0)|(1<<RXEN0);

    	// Datenformats: 8 Datenbits, 1 Stoppbit 
    	UCSR0C |= (1<<UCSZ01)|(1<<UCSZ00); 

}



void USART_Transmit( unsigned char data )
{
/* Wait for empty transmit buffer */
while ( !( UCSR0A & (1<<UDRE0)) );
/* Put data into buffer, sends the data */
UDR0 = data;
}


unsigned char res(void)
{
	unsigned char x;
	while ( !(UCSR0A & (1<<RXC0)));
	x=UDR0;
	while ( !(UCSR0A & (1<<TXC0)));
	UDR0=x;
	
	return x;


}



int main() 
{ 

    Uart_Init(); 

    
   while(1)                        //Reaktion in Schleife 
   { 
		
		res();		// echo zurück senden
	
   }
}