I used 4 line SPI interface . I can respectively sucess use Dout and Din to send and receive data in different project. So it prove 4 lines SPI subscription success . If i want to use PC send one byte to 2686 , the Din of SPI will Receive data . After SPI Read Bus Received data , then i will use Dout of SPI to send data which 2686 get . But it cant work . Finially i saw oscilloscope , Din of SPI will get data . But why 2686 still use Din
of SPI to send data , not Dout of SPI ? Is it a bug of 2686 to use bidirectional SPI Interface?