PXI 5412 Triggering - Delay Error

[jhoodncl]

Good morning,

I'm trying to write a VI to trigger two AWGs, with a non-zero nµs delay between the waveforms. (5 < n < 500)
Both AWGs are model PXI 5412, running in arbitrary waveform output mode.

I export a marker event to the PXI backplane from the master AWG, and trigger the second AWG using this marker.
However, I am seeing the delay between the two waveforms vary, in no relation to the specified offset position of the marker event.

Please find attached my VI - written on LabVIEW 7.1 as the system is running on a PXI-1042 chassis with no other LV license installed.
I've also attached 3 photos of the output to an oscilloscope - it can be seen that the delay between the master (yellow, upper trace) and slave (blue, lower trace) is not constant, varying from 50 to >300µs with exactly the same parameters chosen. I expected a delay of ~500µs, i.e. 1kHz waveforms in antiphase.

I have also tried using TClk synchronisation, which works to synchronise the waveform initiation, but does not permit any delay, beyond the 10ns adjustment available with the Sample Clock Delay property.

Is it possible to combine triggers and TClk sync to achieve a delay between the master and slave waveform initiation?
Or is there a way simpler way to achieve a multiple-µs delay between two waveforms?

Any help would be much appreciated.
James

[jackstokley]

Hi James,

I've got a couple of pieces of information which may help you out. The first is a little information on timing and syncronisation within LabVIEW 7, and the second is that there is an example included in some versions of LabVIEW in the example finder which has the functionality you explain here.

http://www.ni.com/product-documentation/4322/en/

http://www.ni.com/example/27903/en/

Regards,

Jack