Hi all,
I'm using the DAQmx 2022 Q3 C API, but basically the issue should be the very same with LabVIEW etc.
My hardware platform is a cDAQ-9181 chassis (1 slot) with a 9402 digital module.
I'm using all 4 digital channels to measure tacho signals (via DAQmxCreateCICountEdgesChan), which works perfectly well.
The issue I have is: The tasks are not synchronized. Basically, the start times of the measurements depend on the start times of the specific counter tasks, which start one after the other with a certain delay.
What I'm trying to do now is to have all four counters receive the same arm-start trigger signal, so that they start at exactly the same time.
As far as I can see, I don't have a suitable trigger signal available. I don't have an analog task where I could export the start trigger. I did import the "/dev/Ctr0ArmStartTrigger" (DAQmxSetDigEdgeArmStartTrigSrc, no error returned) on all other counters 1-3, and started counter 0 last, but that does not trigger the counters 1-3 at all.
Does anyone know how my problem could be solved?
BTW: If I switch to a larger chassis, say the cDAQ-9185, add an analog channel and use its start trigger, everything works fine. I just don't have an analog channel on the cDAQ-9181 with the 9402 module.
Thank you very much!