Execute commands at particular frequency

4 posts / 0 new

Thu, 11/23/2017 - 07:43

BR_Innes

Hi,

I'm using the Labjack U3-LV with the Matlab UD to trigger a device. I basically use code from the u3_simple demo to set output FIO4 high and low.
I was wondering if there was a way to set up the LabJack so that these two requests were repeated at a particular frequency (e.g. 50Hz) for a specific number of times (e.g. 100 repeats). Is there a way to set up a timer to do this?

Thanks

Sat, 11/25/2017 - 16:47

LabJack Support

Consider using a PWM16 timer

Consider using a PWM16 timer and another timer in STOP mode:

https://labjack.com/support/app-notes/waveform-generation

Tue, 11/28/2017 - 07:54

BR_Innes

Thanks for your answer, I

Thanks for your answer, I followed example code on setting up a timer in stop mode and this solution works for me.

I was wondering is it possible to extend this to deliver more complex pulse patterns e.g. if I want to deliver 10 pulses at 50Hz every 0.5s (2Hz) for a total of 100 pulses, would I need to set up additional timers to control this?

Tue, 11/28/2017 - 10:12

LabJack Support

There is no way to do that in

There is no way to do that in hardware on the U3. I suggest you use a software timer in Matlab to make a loop iterate every 500ms. Each time the loop iterates you have it configure the timers to do 10 pulses at 50 Hz.