AD7616 SPI interface no response

Hi, Sir

  I want to use the AD7616 with SPI interface with Software mode.

  I try to check the SPI interface by write and read the registers.

  

  Are there any setting I need to check ?

  Below is my setting now

  1. CHSELx -> Not set, let it be default value

  2. DB0/1/2/3/4/5/6/7/8/9 -> GND

  3. DB13/14/15 -> GND

  4. CS -> SPI-CS

  5. SCLK/RDb -> SPI-SCK

  6. DB10/SDI -> SPI-MOSI

  7. DB12/SDOA -> SPI-MISO 

  Are these setting OK ?

  Thank you~