Losing trigger to camera with FPGA 8254R

[Dreamer]

Hi to everybody,

I'm getting a very serious problem I don't now how to overcome...

We collect images to be analyze using NI PCI-8254R board and LBV8.5 with Vision Dev 8.5.  I have 2 AVT 1394 Guppy cameras running in Mode 1 trigger. Our process get 3 images/sec and we run geometric match on it.

The system works in this way:  I have two inductive sensors looking for the parts coming, when the parts arrive a high signal is forward on the IsoInput 5 or IsoInput 8 of the FPGA and the FPGA should send a pulse signal over TTL Pulse 1 or Pulse 4 to the correct cameras for the trigger and getting the image.  The procedure is clearly shown also on NI documentation..

Everything works well for 97% of the time (hundreds of images)...but sometime randomly the FPGA receive the trigger but will not send the pulse...and I miss the image...

Useless to say I check everything already...the sensors, the cables, the cameras, the power...everything works well, without noise.

I tried to skip also all image process and later on also grap process...just the simple routing..and sometime we miss it..  WHY?

We checked if it was a point of pulse width and delay that maybe it was to long for the frequency of signal routing, but even with loo frequency (3 parts/sec) sometime we miss the signal..

It could be 8254 FPGA has a problem running two process in parallel? Maybe FPGS sleep sometime??

Using an oscilloscope, we saw a ratio between width and missing signal with high frequency (over 6-7 parts/sec), but we can't understand why we miss also the first image, sometime and not running 1-3 parts/sec....

I attached a simple test I did to check the routing...I also change two 8254 cards, and the problem still appear...

I thank you very much for any comment and suggestion... My brain is gone on that....

I need to solve this issue and I cannot miss one image in this process.

Marco

[Chuck_81]

Hi Marco,

here at NI-Italy we are facing a similar issue with one of our customers. We're performing some tests to verify if this could be an HW issue related to the board itself or if we can provide a workaround for this.

I'll reply to you as soon as possible with new informations,

Best regards,

Fabio

[Vladimir_Drzik]

Hi Fabio

Is there any progress on this issue?

Vladimir

[Chuck_81]

Hi Vladimir,

i have to speak with the guy here who dealt with this issue. I'll reply to you as soon as possible,

Best Regards,

Fabio