Robotiklubi

/*
 * USART main.c
 *
 */ 
 
#include <avr/io.h>
#include <util/delay.h>
 
void send_string(uint8_t *data)
{
	for (; *data != '\0'; data++)
	{
		while (!(UCSR0A & (1<<UDRE0)));
		UDR0 = *data;
	}
}
 
void send_char(uint8_t c)
{
	// Wait till data buffer empty
	while(!(UCSR0A & (1<<UDRE0)));
	// put data to buffer
	UDR0 = c;
}
 
void rec_string(uint8_t *arr, uint8_t len)
{
	uint8_t top = len - 1;
	uint8_t i;
 
	for (i = 0; i < top; i++)
	{
		while (!(UCSR0A & (1 << RXC0)));
		arr[i] = UDR0;
	}
 
	arr[i] = '\0';
}
 
uint8_t rec_char()
{
	// Wait data buffer
	while(!(UCSR0A & (1<<RXC0)));
	// get data from buffer
	return UDR0;
}
 
int main(void)
{
	UBRR0 = 103; // baud 9600
	/* Enable Tx and Rx */
	UCSR0B = (1<<RXEN0)|(1<<TXEN0);
	/* Set frame format: 8data, 2stop bit */
	UCSR0C = (1<<USBS0)|(3<<UCSZ00);
	DDRD = (1<<1); // Tx as output
 
	while(1)
	{
		/*tagastab saadud väärtuse*/
		send_char(rec_char());
	}
}