Mirror area of external address space xSPI0和External address space xSPI0的区别

如题,请问Mirror area of external address space xSPI0和External address space xSPI0在读写访问上有什么区别?

我尝试使用如图所示代码进行验证,发现对Mirror area of external address space xSPI0区域进行写操作后,从Mirror area of external address space xSPI0读出来的数据不对,但是从External address space xSPI0读出来的就是对的。