UART位，奇偶校验和停止位设置

问候语！你能给我解释几件事吗？我做了一些测试，我注意到RCSTA和TXSTA寄存器没有区别，如果我使用7位数据或8位带有N奇偶校验。只有当我尝试使用E或O奇偶校验的8位数据（TX9和RX9位）时，差异才会出现。一个00774表示如果我设置相同的位（RX9和TX9），我可以2位停止。那么控制器是如何找到如果我使用O/E或2个停止位？为什么两个停止位和O/E之间没有差异，那么这些选项是2个停止位？我读过有错误检测，但是这两种方法都可以用来检测错误……你能给我更多的信息吗？谢谢！



      以下为原文

    Greetings! Can you explain to me a few thing? I ran a few test and I`ve notice there is no difference in RCSTA and TXSTA registers if I`m using 7bit data or 8bit with N parity. The difference comes only when I try to use 8bit data with E or O parity(The TX9 and RX9 bits are set).
So how the controller makes difference between O or E parity? AN 00774 says I can you 2 stop bits if I set the same bits(RX9 and TX9). So how the controller is going to find if I`m using O/E or 2 stop bits? And why these is such options as 2 stop bits if there is no difference between 2stop bits and O/E?!
I read there are used for error detection, but both of these could be used are error detection...
Can you give me any more info about these thing?
Thanks!