Serial communication, USART, LUFA Library, AVR

Communication.c

#include <stdio.h>
#include <avr/interrupt.h>
#include <LUFA/Drivers/Peripheral/Serial.h>

#define MAX_BUFFER 32
char b[MAX_BUFFER];
uint8_t l = 0;
ISR(USART1_RX_vect) {
  char c = fgetc(stdin);
  printf("%c", c);
  if (c == '\r') {
    printf("\r\n<< %s\r\n>> ", b);
    l = 0;
    memset(b, 0, sizeof(b));
  } else if (c != '\n' && l < MAX_BUFFER) {
    b[l++] = c;
  }
}

int main(void) {
  Serial_Init(9600, false);
  Serial_CreateStream(NULL);

  sei();
  UCSR1B |= (1 << RXCIE1);

  printf("{{ Ready }}\r\n>> ");

  for(;;);

  return 0;
}