07-24-2017 10:44 AM
Hello,
I have made a sort of step sequencer which will be used to trigger lasers on and off in different sequences which can be preconfigured. The vi will run each segment for as long as the user wants through a numeric control. This is used as part of an experiment where the lasers when fired will excite a material which is then captured by a camera. The camera can output ttl pulses for each frame it takes. at the moment this VI is used through inputing the time in ms that is equivalent to each frame taken but due to different internal clocks of the camera and pc this gets out of syncrhonisation after a while so I am thinking of controlling the sequence with number of frames rather than time passed. I will attach my VI and would like to know if anyone have any ideas how I can use a TTL input from a camera to control my step sequencer. If this doesn't make much sense please ask and I'll clarify whatever you need.
Regards,
Jaafar Harari
PS. the force quit button isn't working as its supposed to atm so ignore it please
07-25-2017 10:57 AM
Hello Jaafar,
I will look more into this, but as a general advice, could you upload a version that is a few years older than the current version. This way users with older LV Versions can also see your code.
Kind regards,
Abdullah AL-Zibdeh
07-26-2017 09:01 AM
Hi Abdullah,
Thank you for your consideration. I will upload a labview 2012 version of the vi and if anyone wants an older version just ask and i shall provide 🙂
Regards,
Jaafar Harari
07-27-2017 05:11 AM
Hello Jaafar,
Have you considered to programmatically control the time of the loop? basically modifying the wait ms to read the timing from your hardware.
If you want to use a different timing/tick counter to control the execution, you can add a loop and use some logic (based on ttl) to stop that loop (create some sort of a timer VI) and then continue executing your top-level VI and so on.
Also something that you should keep in mind is that this is all software timing and you might have jitter and some delays...etc due to your processor getting busy working on other applications.
Best regards,
Abdullah
07-27-2017 08:53 AM
Hello Abullah,
I will try to do that. But about the Wait(ms), how can i set it up to read from my hardwares since as far as I know it only takes in numeric constants or have I missed something?
Thank you,
Jaafar
07-27-2017 09:12 AM
Hello Jaafar,
I meant that you can programmatically utilize the output of your hardware to manipulate the wait time. What is the output from your hardware?
Thanks,
Abdullah
07-27-2017 10:07 AM
Hello Abdullah,
The output form the camera is strictly a ttl pulse.
Regards,
Jaafar