ADS4226EVM: SPI Issues when accessing through a FPGA

For the 4226 EVM, I have interfaced that to a FPGA.

Therefore, I have swapped the zero-ohm links from the USB SPI with the  FPGA SPI.

The signals, SCLK, SS_N, and SDATA, into the ADC are working (As SDOUT is replying). However if I read back the configuration from the ADC via the SPI, the following occurs:

* Write Address: x00, Data: x01

* Read Addresses: x01 to xF2 inclusive

* When reading back the first non-zero register,  SDOUT  correctly outputs the value e.g. Read Address: x25, Read data: x05

* But, SDOUT goes high-impedance for the rest of the reads.    

I'm sure I'm missed something?

Thanks