11-05-2015 10:12 AM
Dear NI members,
we are working on a microscope driving application, written in C by using the NIDAQmx driver. We create a digital input task and we asign a Change Detection event for it. From the microscope a 8kHz signal will arrive every time the scanner starts acquisition and that signal will stop after acquisition is done. To detect the start point we are looking for the first change in signal from low to high. We are having issue of detecting the end point, as the number of 8kHz pulses sent by the scanner can be different. What is the best way to detect that the signal is not arriving anymore?
The card we are using is NI PCIe-6321.
Thank you in advance for any ideas.
Best,
Georgi
11-16-2015 05:01 AM - last edited on 01-08-2024 02:36 PM by migration-bot
Hi Georgi,
if I understand correctly, what you need is to implement a start and a stop trigger for your aquisition.
Have a look at this Knowledgebase Article, it might answer your question:
How Do I Use a Digital Trigger in LabVIEW to Start and Stop Acquiring Data? - National Instruments
https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019MiHSAU&l=en-US
Also, possibilities are listed in following WhitePaper:
Tips and Techniques in Data Acquisition Triggering - NI-DAQmx - National Instruments
https://www.ni.com/en/support/documentation/supplemental/21/ni-daqmx-data-acquisition-triggering-tec...
I hope this helps!
Best wishes,
Monika