I have browsed other posts and used the GPO pin to check the "clock ouputs phase status", while there is a problem.
The 0x0046 is programmed by 0x00 and 0x0050 is programmed by 0x0F, the GPO status received by FPGA is always high.That is just after power up.
After that, I tried to set 0x0050 with 0x2D, got same result.
The circuitment between HMC7043 and FPGA as show blew:
When 0 ohm resister is tested by oscilloscope, the voltage is around 180mV.
We're looking forward to your reply. Thanks