AD9643 SPI Write Problem

[jason_bill]

Hi,

I want to write to the AD9643 Register through SPI interface by FPGA.
I have developed spi core. Read operation work correctly becuase when i read value of register
it returns the default values as same as is mentioned in the data sheet.

But the write operation not work. for example i want to set the 0x0B to 0X03 such as picture 1 but it returns default value again!

 

[FvM]

SPI clock phase doesn't seem to be right in the diagram, also the meaning of MISO and MOSi signals isn't clear because AD9643 has a bidirectional SDIO line.

 

[jason_bill]

Thanks,
I assigned SDIO as below:

assign sdio = (spi_dir)? 1'bz : mosi_sig; 
assign miso_sig = (spi_dir)? sdio : 1'b0;

when R/W bit equal '1' spi_dir is asserted by spi core.

 

[FvM]

when R/W bit equal '1' spi_dir is asserted by spi core

I presume, it's asserted in the data phase only.

More generally speaking, you have a Verilog design operating the interface, of course the timing diagram doesn't give the design details. Did you understand about the wrong clock phase that I mentioned?