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Read HMC1197's registers but only get Reg 00h's value


I'm trying to communicate with HMC1197. I can read Reg00h's value(C7701A). But when I tried to read any other READ ONLY register, like Reg 07h, I got always C7701A.

Following ,is my scope screen-captures when i want to read Reg 07h

I think my SPI waveform is right. In the first cycle, SDI write 0111b(Reg 07h) at r3:r0. But SDO still C7701A.

And I have read 

and .

But unfortunately, there are little help for me.

Could anybody help me? Thank you!FormerMember