uart.c

来自「手持式GPS导航系统－源码」· C语言 代码 · 共 37 行

#include"UART.h"

//#include<stdio.h>



int USART_putchar(char CH)
{
	/* Wait for empty transmit buffer */
	while ( !( UCSRA & (1<<UDRE)) );
	/* Put data into buffer, sends the data */
	UDR=CH;
	return 0;
}


int USART_getchar(void)
{
 	/* Wait for data to be received */
	while ( !(UCSRA & (1<<RXC)) );
	/* Get and return received data from buffer */
	return UDR;
}


void COM_Initial(unsigned int UBRR_val)
{
	/* Set baud rate */
	UBRRH = (unsigned char)(UBRR_val>>8);
	UBRRL = (unsigned char)UBRR_val;
	/* Enable receiver and transmitter */
	UCSRB = (1<<RXEN)|(1<<TXEN);
	/* Set frame format: 8data, 2stop bit */
	//UCSRC = (1<<URSEL)|(1<<USBS)|(3<<UCSZ0);
	fdevopen(USART_putchar,USART_getchar);//
}