We connected a 8 MHz signal generator to the device in order to sync up the ADCs and DACs and hopefully get phase data. 

Some things to note:

• RF Manual (143)- Need to use XRFDC SYSREF for update event
• RF Manual (171)- Synchronization steps require us to first enable all clocks and sysref generators (via xrfdc package)
• RF Manual (173)- Sysref requirments, not clear if PL is syncing as needed.
• RF Manual (181)- XRFDC example code, see also https://github.com/Xilinx/embeddedsw/blob/master/XilinxProcessorIPLib/drivers/rfdc/examples/xrfdc_mts_example.c

Xilinx RF Manual: https://docs.xilinx.com/v/u/2.4-English/pg269-rf-data-converter