I found api in iio.h, such as iio_device_reg_read & iio_device_reg_write.
But I don't know how to use them via Matlab.
Would you give me some advice please?
The "MATLAB/Simulink Examples" section of this wiki page: AD-FMCOMMS2-EBZ User Guide [Analog Devices Wiki] contains examples on how to use libiio via Matlab.
If you are trying to do low level register access on the AD9361 - that means something isn't working. Maybe you can describe what you are trying to do, and why you think you need to program the registers directly?
Retrieving data ...