/** Functions for serial port **/
  
  #include <avr/io.h>
  #include <stdio.h>
  
  #include "serial.h"
  
  static int send_serial_printf(char c,FILE *stream);
  static FILE mystdout=FDEV_SETUP_STREAM(send_serial_printf,NULL,_FDEV_SETUP_WRITE);
  
  void init_serial(int speed){
  /* Set baud rate */
  UBRR0 = F_CPU/(((unsigned long int)speed)<<4)-1;
  
  /* Enable transmitter & receiver */
  UCSR0B = (1<<TXEN0 | 1<<RXEN0);
  
  /* Set 8 bits character and 1 stop bit */
  UCSR0C = (1<<UCSZ01 | 1<<UCSZ00);
  
  /* Set off UART baud doubler */
  UCSR0A &= ~(1 << U2X0);
  }
  
  void send_serial(char c){
  loop_until_bit_is_set(UCSR0A, UDRE0);
  UDR0 = c;
  }
  
  char get_serial(void){
  loop_until_bit_is_set(UCSR0A, RXC0);
  return UDR0;
  }
  
  void init_printf(void){
  init_serial(9600);
  stdout=&mystdout;
  }
  
  static int send_serial_printf(char c,FILE *stream){
  if(c=='\n') send_serial('\r');
  send_serial(c);
  return 0;
  }