Hi,
This question appears related to the issue I am having where I'm unable to use a feedback mixer to mix down the internal VCO RF output back to the PFD input pin. I am setting R57 and R15 as follows:
R57 = 0x0000
R15 = 0x2601
These are the same settings that are generated in the TICs when the corresponding feedback paths are selected in the GUI. As far as I can tell, this sets the Single PFD.
When I disconnect the RF feedback, the synth does not lose lock.
Jon
