10-13-2016 06:37 AM
I am trying to synchronize two PCIe boards, which are connected by a RTSI cable, an S-Series (PCI-6115) and an X-Series (PCIe-6363). I would like to run an AI task on the S-Series (10MHz acquisition) and a synchronous AO task on the X-Series. Among other things, I tried routing the 20 MHz timebase on the S-Series to RTSI7 and then into the refclk.src of the X-Series, but I got an error that the PLL could not lock to the source. It is not obvious to me what timing signal I can route between the two (it seems the S-Series can only export or input a 20MHz signal, and the X-Series a 10MHz). Am I missing something? Thanks in advance for any help!
Solved! Go to Solution.
10-13-2016 07:21 AM
I've done a lot of board & task sync'ing and have almost *never* done any reference clock routing. I generally just route sample clock (and maybe trigger) signals over the timing bus. RTSI on a desktop, backplane on a PXI chassis.
You should be able to define your AO task to use the S-series task's sample clock as its timebase and then define a timebase divisor to set an AO sample rate. Then start your AO task before the S-series task. There's a good chance that alone will get you close enough (with some nanosec of signal propagation time), without dealing with triggers or reference clocks.
-Kevin P
10-13-2016 05:13 PM
That worked perfectly for me - thanks for the advice!