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/* #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
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