/* #define F_CPU 16000000UL <= defined in Makefile */
#define BAUD 9600

/* This file is *highly* inspired from:
 * http://www.appelsiini.net/2011/simple-usart-with-avr-libc
 */

#include <util/setbaud.h>

#if 0
static inline void uart_init()
{
    UCSRB |= (1 << RXEN)  | (1 << TXEN);
    UCSRC |= (1 << UCSZ0) | (1 << UCSZ1);
#define BAUD 115200
#include <util/setbaud.h>
    UBRRH = UBRRH_VALUE;
    UBRRL = UBRRL_VALUE;
#if USE_2X
    UCSRA |= (1 << U2X);
#else
    UCSRA &= ~(1 << U2X);
#endif
}
#endif

void uart_init(void)
{
    UBRR0H = UBRRH_VALUE;
    UBRR0L = UBRRL_VALUE;

#if USE_2X
    UCSR0A |= _BV(U2X0);
#else
    UCSR0A &= ~(_BV(U2X0));
#endif

    UCSR0C = _BV(UCSZ01) | _BV(UCSZ00); /* 8-bit data */
    UCSR0B = _BV(RXEN0) | _BV(TXEN0);   /* Enable RX and TX */
}

void uart_putchar(char c)
{
    UDR0 = c;
    loop_until_bit_is_set(UCSR0A, TXC0); /* Wait until transmission ready. */
}

char uart_getchar(void)
{
    loop_until_bit_is_set(UCSR0A, RXC0); /* Wait until data exists. */
    return UDR0;
}

#if 0
/* alternatives for stream uses */
void uart_putchar(char c, FILE *stream)
{
    if (c == '\n') {
        uart_putchar('\r', stream);
    }
    loop_until_bit_is_set(UCSR0A, UDRE0);
    UDR0 = c;
}

char uart_getchar(FILE *stream)
{
    loop_until_bit_is_set(UCSR0A, RXC0); /* Wait until data exists. */
    return UDR0;
}
#endif

#if 0
FILE uart_output = FDEV_SETUP_STREAM(uart_putchar, NULL, _FDEV_SETUP_WRITE);
FILE uart_input = FDEV_SETUP_STREAM(NULL, uart_getchar, _FDEV_SETUP_READ);
FILE uart_io FDEV_SETUP_STREAM(uart_putchar, uart_getchar, _FDEV_SETUP_RW);
#endif