尽量不要用delay。。。这不是RTOS

想要好的实时性，所有时基都应该由中断实现

这种东西要用状态机写的，你也没有判断是否存在数据，也没有做校验，都是不可靠的，有一个获取缓冲区有多少byte的函数

然后取一个数据，调用状态机去处理，类似下面我写的寄代码

          while (Serial.available() > 0)  //循环串口是否有数据
          {

void Data_chuli(uint8_t readbit){
  static uint16_t data_len=0,data_readlen=0,data_crc=0;
    switch(uart_ztj){
      case 0:
        if(readbit==0xBE){
          read_data[0]=readbit;
          uart_ztj=1;
        }
        break;
      case 1:
        if(readbit==0xAA){
          read_data[1]=readbit;
          uart_ztj=2;
        }else{
          uart_ztj=0;
        }
        break;
      case 2:
        data_len=readbit;
        read_data[2]=readbit;
        uart_ztj=3;
        break;
      case 3:
        data_len+=readbit<<8;
        read_data[3]=readbit;
        if(data_len<=DATA_BUF+1){
          uart_ztj=4;
        }else{
          uart_ztj=0;
        }
        break;
      case 4:
        data_status=readbit;
        read_data[4]=readbit;
        if(data_len==1){
          uart_ztj=6;
        }else{
          uart_ztj=5;
        }
        data_readlen=1;
        break;
      case 5:
        read_data[data_readlen+4]=readbit;
        data_readlen++;
        if(data_readlen>=data_len){
          uart_ztj=6;
        }
        break;
      case 6:
        data_crc=readbit;
        uart_ztj=7;
        break;
      case 7:
        data_crc+=readbit<<8;
        uart_ztj=8;
        break;
      case 8:
        if(readbit==0xEB){
          uart_ztj=9;
        }else{
          uart_ztj=0;
        }
        break;
      case 9:
        if(readbit==0xAA){
          uart_ztj=0;
          if(CRC16_XMODEN(read_data,data_len+4)==data_crc){//成功接收
            read_en=0;
          }
        }else{
          uart_ztj=0;
        }
        break;
    }
}