myuart.c

atmega128单片机串口调试程序

#include"includes.h"

/*USART initiate*/
U8 rx_flag;   //接收数据标志
U8 rx_buff;   //接收数据缓存区

void uart0_init(void)
{
    UBRR0H = BAUD_H;     
    UBRR0L = BAUD_L;            //Set baud rate 
    UCSR0C = 0x0E;            //Set frame format: 8data, 2stop bit 
    UCSR0B = ((1<<RXCIE0)|(1<<RXEN0)|(1<<TXEN0));   //Enable Receiver and Transmitter 
		   	 	//1：接受中断
				//0：关闭中断
}

//接收中断
#pragma interrupt_handler uart0_rx_isr:19
void uart0_rx_isr(void)
{
    //uart has received a character in UDR
    PORTA=UDR0; //接收数据并输出到PA
}

//发送中断
#pragma interrupt_handler uart0_tx_isr:21
void uart0_tx_isr(void)
{
}

//USART0 数据寄存器空中断
#pragma interrupt_handler uart0_data_isr:20
void uart0_data_isr(void)
{
}

//call this routine to initialize all peripherals



//从RS232发送一个字节 
void uart0_putchar(char c)
{ 
    while(!(UCSR0A & 0x20)); 
    UDR0 = c; 
} 

//输出一个字符串
void uart0_putstr(char* str)
{
	while(*str)
	{
		uart0_putchar(*str);
		str++;
	}
}

//从RS232接收一个字节 
int uart0_getchar(void) 
{ 
    unsigned char status,res; 
    if(!(UCSR0A & 0x80)) return -1;        //no data to be received 
    status = UCSR0A; 
    res = UDR0; 
    if (status & 0x1c) return -1;        // If error, return -1 
    return res; 
} 

char uart0_waitchar(void) 
{ 
    int c; 
    while((c=uart0_getchar())==-1); 
    return (char)c; 
}