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AD9633EBZ SPI communication with ZedBoard

Question asked by z00345up on Oct 28, 2014
Latest reply on Nov 3, 2014 by rejeesh

I am using the AD9633-125 EBZ, interfaced to the ZedBoard over FMC. I would like to be able to read and write the ADC's registers using SPI. I have been trying to use the PS7's SPI ports with no success. I used the reference design on github for the fmcomm2 to mimic the connections between the PS's SPI ports and the external ports. The block design and the SPI connections made in system_top.v with the underlying wrapper and PS are identical. I am using Vivado 2014.3.


In system_top (layer above wrapper of block design), the CS input is asserted as high, and the rest of the connections are as follows.

  .spi_csn_i (1'b1),

  .spi_csn_o (spi_csn),   

  .spi_miso_i (spi_miso),

  .spi_mosi_i (1'b0),

  .spi_mosi_o (spi_mosi),

  .spi_sclk_i (1'b0),

  .spi_sclk_o (spi_clk)


For the SW, I used the SW from no-OS-master repository on github for the AD9361 to include the basic read and write functions, as well as the initialize procedure which seems to work (reads the correct base address and control register). Still, all I can read is 0x0 on all registers.


In terms of physical pinouts:

SCLK_O is connected to G27 on the FMC (D22).

CS0_O is connected to D26 on the FMC (F18).

MOSI_O is connected to H29 on the FMC (A19).

MISO_I is connected to H28 on the FMC (A18).


By probing the pins on the FMC interposer coming from the P1001 connecter, I can see that the clock and chip select pins are being driven. There seems to be nothing on the SDI or SDO pins.


Does anyone have any ideas as to what may be the problem? Please let me know what other information, screenshots or code I can include. Thanks.