I'm working on a system that uses the analog output of my USB-6001 DAQ to drive scanning mirrors very quickly. This system has to be synchronized with my niScope (PXIe-5122) which I'm using to acquire data. The external trigger signal that I'm trying to use to time both devices is 4kHz (period of 250us). I'd like to be able to be able to update the analog output of my DAQ every 1 or 2 or 4 trigger edges to a new, but predetermined value. I need 2 analog outputs, doing x and y scanning respectively.
Can anyone shed light on how to do this?
1. I need to be able to read the trigger signal
2. I need to use the trigger to update the analog outputs on two channels
3. I need flexibility on when the change happens relative to the edge (maybe a trigger delay or holdoff).
Anything helps. If you can think of a different scheme to synchronize these devices, that'd also be appreciated.
so you want:
To have an external signal at 4kHz that triggers the outputs of the 6001 and the inputs of the 5122, and
To have the analog outputs of the 6001 to be updated every 1,2 or 4 trigger edges.
I got lost when you said the analog outputs were going to do scanning, I guess you meant to update the values, by definition an output does not scan.
As a reference for the synchronization, this is a guide for synchronization using DAQmx*
*NOTE: the 5122 uses a different driver (NI SCOPE)
I would start triggering one device, make sure that it works, then triggering the other, make sure it works, and then, put everything together
by the way, what are scanning mirrors?
Yes the 6001 just updates voltages via analog outputs (what those voltages do is unimportant, i was just trying to give some context). Ideally, I wouldn't have to change anything about how the 5122 is implemented.
So how do I use a 4kHz trigger signal to update analog output values as quickly as possible with as little overhead as possible.
Trigger the analog output with the external source
Check on this
Tips and Techniques in Data Acquisition Triggering - NI-DAQmx
You can use the DAQmx analog output examples, look for one that fits your the output you want to have and use an external trigger on the triggering VI