Square wave generator with a NI4351

[IOT Projekt]

Hi, my name is Gestur...
I am trying to generate a variable square wave generator using one of the digital output lines on a PCI-NI4351 digital multimeter card. My signal is unstabel unless the frequency measures 5Hz or lower!! I am using a while loop with a shift register and a Case with boolean True and False states. Furthermore I have been using a variable timer/delay to change the frequency. I need comments and/or alternatives

[Jack_A.]

I tested your program here and I am able to get a fairly stable square wave at 50 Hz (time delay of 10ms). This square wave is software timed and any other processes which occur on your PC will slow down your loop rate and make you waveform less stable. So this VI is very PC specific. The PCI-4351 does not have a counter on it so it is not geared towards performing as a stable waveform generator. If you do need that, I would recommend one of our low cost E-Series boards.

This is really the only way to create a square wave with this board since the DIO is static. You can increase it's stability by trying to reduce the amount of other programs running at the same time as well as user interaction with the PC. You could also try it on a faster PC.

Hop
e this helps.

Jack Arnold
Application Engineer
National Instruments

[IOT Projekt]

Thank you Jack, this is just what I thought. Now I'm sure and can proceed with my project.
Again thanks... and maybe we'll talk later 🐵