DDRB = 0xFF;           /*方向输出*/
PORTB = 0xFF;
   UCSR0A = (1 << U2X0);         /*倍速*/
UCSR0B = (1 << TXEN0) | (1 << RXEN0);     /*允许接收和发送*/
UCSR0C = (1 << UCSZ01) | (1 << UCSZ00);     /*8位数据、1 位停止、异步、无校验*/
UBRR0H = 0x00;
UBRR0L = 12;           /*波特率9600*/
}

/*数据发送，查询方式*/
void Printf(unsigned char *P) {
     do{       
while (!(UCSR0A & (1<<UDRE0)));       /* 等待发送缓冲器为空*/
UDR0 = *P;            /* 发送数据*/
        P++;
        }
      while(*P!='\0');
   
while (!(UCSR0A & (1<<UDRE0)));        /* 等待发送缓冲器为空*/
UDR0 = 0x0D;            /* 发送回车数据*/
    while (!(UCSR0A & (1<<UDRE0)));        /* 等待发送缓冲器为空*/
UDR0 = 0x0A;            /* 发送换行数据*/
}