in my project, i use NI PXI-1024Q chassis, NI PXI-8109 controller, and one PXI-6682H as timing module and one PXI-4461 as DAQ module.
i hope to:
A. use 6682H as a 1588(ptp) client( or to which connect a GPS ant.), to get high accuracy time, synchronized with GPS time.
--this step is done. i used "niSync Create Clock" vi etc., and such clock is available on PFI 1.
B. share this clock via PXI bus, so that it's available for 4461.
--i've got some difficulties now. in "DAQmx timing" vi, the only choice for 'sample clock source' is 'onBoardClock', according to the error 200077 report, when i tried to connect this attribute with PXI-CLK10, 6682/PFI0 and so on.
C. if step B is done, i'll be able to make AO or AI with high time accuracy.
--with a high accuracy clock synchronized with GPS, there would be a good sample clock and a trigger source, both synchronized with GPS.
btw, i've found that 6682/PFI0 is a valid trigger source for DAQmx vis. so the bottleneck for my questions should be Step B.
what's more, i found in this forum the following idea, not mentioning how to discipline GPS with 6682's clock:
...PXI6682 is not able to generate a 10MHz clock that is discipline to GPS. what you can do is have PXI-clk10 driven by PXI-6682's higher stability 10MHz TCXO, but this 10MHz signal will be free-running, not disciplined to GPS.
