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PXIe-5413 No output on PFI connectors

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I have a 5413 in a PXIe-1075 chassis.  I'm having a problem getting signals out the PFI 0 an PFI 1 connectors.  I want to use those outputs to trigger other 5413 cards. 

 

I get the intended signals out of Ch 0 and Ch 1 so I can communicate with the card and have no reason to think there's a hardware issue.  I've verified no pulse/trigger out on the PFI connectors with an oscilloscope.  A screen grab of my code is attached (sorry, can't send actual code).

 

See any problems with the code?

 

 

John

"Praise the Lord and pass the ammunition."- Lt. (j.g.) Howell Forgy, Sky Pilot, USS New Orleans, 12/7/41
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It's unclear which PFI line you configure first in the screenshot of the code. But what is happening is that the second call re-configures and overwrites the first one.

 

Try making the configuration call once with value "PFI0,PFI1" if you want to export the signal to both destinations, rather than overwrite the configuration by calling twice.

Marcos Kirsch
Chief Software Engineer
Core Modular Instruments Software
National Instruments
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Hi Marcos, thanks for the reply.

 

Sorry about the overlap of constants in the screen shot.  It was one of those things you see after you hit send.

 

Changing the configuration call as you suggested didn't change the performance, and actually caused an error further down the line. 

 

I did find/learn two things:

  • I was expecting the "trigger" out of the PFI0 and PFI1 ports to be a continuous pulse train (one for every pulse out of Ch0 and Ch1).  That was an assumption on my part, which was wrong as a colleague pointed out to me.  I equate the word "enable" to single events, not "trigger".  My bad.  Something in the documentation explicitly saying this would be nice.  Setting the o'scope trigger appropriately showed that the PFI0,1 pulses were there, sometimes.
  • The real fix was to set the first NI FGEN VI (far left on image) Reset to TRUE.  That made everything behave as expected, consistently.  Problem solved. 

 

Thanks!

John

"Praise the Lord and pass the ammunition."- Lt. (j.g.) Howell Forgy, Sky Pilot, USS New Orleans, 12/7/41
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