I have a problem when I communicate with mfrc522 use Uart.

Hi,all;

These days , I am learnning rc522. Today , I did a simple test. I use Uart communicate with rc522. I want to read the value of the register 0x01.But I find the rc522 always returns the same number I send to it .

As the picture above. When I want to read the value of the register ,I should set MSB = 1;and I have set it .

I send 0x81, and the module returns 00, 81...........But I think it should returns 20h......?

How can I get 20h?!