#define F_CPU 8000000UL
#include<avr/io.h>
#include<avr/interrupt.h>
#include<util/delay.h>
#define INT8U unsigned char
#define INT16U unsigned int
#define BAUDRATE  9600
struct
 {
 INT8U Buf_Array[100];
 INT8U Buf_Len;  }
Receive_Buffer;
INT8U Clear_Buffer_Flag=0;
const INT8U SEG_CODE[16]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x00};//数码管断码表显示0123456789
char*s="只是AVR向PC机发送的字符串！ ",*p;  
 
 void Init_USART()
  {
  UCSRC=(1<<URSEL)|0x60;
 UBRRL=(F_CPU/BAUDRATE/16-1)%256;
 UBRRH=(F_CPU/BAUDRATE/16-1)/256;
 UCSRA=0X00;
 UCSRB=(1<<RXCIE)|(1<<RXEN)|(1<<TXEN); 
 
 }
void PutChar(char c)
 {  if(c==' ')PutChar(' ');
 UDR=c;
 while(!(UCSRA &_BV(UDRE)));
 }
void show_Received_Digits()
 {
 
 INT8U i;
 for(i=0;i<Receive_Buffer.Buf_Len;i++)
  {
  PORTC=SEG_CODE[Receive_Buffer.Buf_Array];
  _delay_ms(400);   } int main()
 {
 Receive_Buffer.Buf_Len=0;
 DDRB=0X00;  PORTB=0XFF;
 DDRC=0XFF;  PORTC=0X00;
 DDRD=0X02;  PORTD=0XFF;
 MCUCR=0X08;
 GICR =_BV(INT1);
 Init_USART();
 sei();
 while(1)show_Received_Digits();
 }
 
  ISR (USART_RXC_vect)
{
 INT8U c=UDR;
 if(c==' '||c==' ')Clear_Buffer_Flag=1;
 if(c>='0'&&c<='9')
 {
 if(Clear_Buffer_Flag==1)
  {
  Receive_Buffer.Buf_Len=0;
  Clear_Buffer_Flag=0;
  }
  Receive_Buffer.Buf_Array[Receive_Buffer.Buf_Len]=c-'0';
  if(Receive_Buffer.Buf_Len<100)
  {
  Receive_Buffer.Buf_Len++;
  }
 }
}
   ISR (INT1_vect)
 {
  INT8U i=0;
 while(s!='')
 {
 PutChar(s[i++]);
 }
 }
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