I wanted to connect the AD9739A FMC Card with an Atlys Spartan-6 FPGA Development Board (http://www.digilentinc.com/Products/Detail.cfm?NavPath=2,400,836&Prod=ATLYS).
I made an adaptor cable that connects the FPGA board (VHDC connector) with the AD9739 FMC board.
Following the reference design from the analog devices wiki (http://wiki.analog.com/resources/fpga/xilinx/fmc/ad9739a) I made a design that configure the DAC, generates the data and clock for DAC and send the data to the DAC's ports.
The problem is that the MOSI signal (FMC_MOSI G36) is tied to 0 by the AD9739A FMC Card. (It is always 0).
I have done osciloscope tests and I have viewed the SPI signals from the ADF4350 chip input. The spi_clk and spi_select signals are ok, but the spi_mosi is always 0.(The microblaze processor runs a C program that continuosly send the 0x00058005 from the FPGA to the DAC through SPI interface). Without the ADF9739A FMC Card connected to the adaptor cable the MOSI signal is ok. (Measured with an oscilloscope on G36 pin).
The jumper on the board is set to FMC position. (we also tried it on the other position, and with no jumper but we got the same results).
Can anyone help me with an idea on where the problem is?