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create a square wave on a rt digital output

Hello,

 

I would like to use labview to generate a very long period square wave and place it on a digital output of a RT target. The output needs to be ON for the initial 30 seconds and then ON for 10 seconds out of every 30 minutes after that.

 

I am new to Labview and I realise that there is probably a simple and elegant solution to this, but I am having trouble finding the right and best function(s) to do the job.

 

Does anyone know how this can be accomplished?

 

Chris

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For those very long time periods, you could just use software timing and turn the digital output on and off when the clock time meets or exceeds the previous time +10 seconds, or +30 minutes, or whatever.  I wouldn't even call it a square wave.  It is just turning the DO on and off.

 

Search the labVIEW forums for message threads discussing long timing applications, perhaps with the word minutes in them.

Message Edited by Ravens Fan on 03-29-2009 10:58 PM
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Thank you.

 

However this does not help me much. I tried to find a discussion as you suggested but with no luck.

 

I understand that using software to turn the DO ON/OFF is what is needed. My question is how is this accomplished? Does anyone know of a link to a similar example? Can someone provided an example of what function(s) are needed and how to connect them?

 

Thanks,

Chris

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Attached is an example showing the code to determine when to turn on and off the digital output.  I am only basing it on the 10 seconds on, remainder of 30 minutes off.

 

You may want to add some preliminary code to intially turn it on, and whatever the special 30 second on condition is.

 

Are you asking how to actually turn on the DO?  It depends on what kind of RT system do you have.  Is it Fieldpoint or a PXI system?  It is generally pretty simple.  Just look in the Example finder to find the method that works with your particular hardware.

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