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Labview FGPA: DRAM / FIFO debugging

Hi,

 

I'm working on a data acquisition system with LV 2013 FGPA and PXIe7966R / NI5734. My program already works for block RAM,

now  I would like to use the DRAM for data storage. How can I probe / view the DRAM (or FIFO) contents in LV FPGA?

I know this might be non-trivial with a compiled VI running on the FPGA, but is it possible when running a simulation on the dev computer?

 

Regards

Michael

 

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You can simulate an FPGA VI that uses DRAM however you may run out of memory if you are trying to simulate 2GB of DRAM. The attached example is a bare bones demonstration of how to simulate a DRAM interface that writes and reads values.

 

Probing the DRAM interface can be done when running the FPGA VI in simulation, but in a compiled VI being run on hardware you would want some controls or indicators put down for debug purposes that can pipe information back up to the host VI.

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Hi David,

 

thank You for You quick reply and the example file. Unfortunately it is made with LV 2014, we have only LV 2013 yet. Would it

be possible to get it in LV 2013 format?

 

I am using an example from the NI course High-Throughput LabVIEW FPGA (Exercise 1-2 Acquire FAM Data (DRAM)) and I'm simulating just a small

amount of DRAM. I now discovered the source of the problem: If I add a constant as the DRAM memory selector, the LV program doesn't work anymore.

Is this a bug or some intended behaviour? How can this be solved?

I attach two pictures, one working example from the High-Throughput LabVIEW FPGA course and one with the modification in the red circle. Output waveform is on the right.

 

Regards,

Michael

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Thats really odd. It works fine for me when I use a constant to define which memory item to use. I'm not sure why that happens for you and not for me.

 

DRAM_simulation.png

 

 

 

 

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I just tried the code You posted with LV 2013. When using a constant, the code is not working.  Otherwise it works fine.

Could You please test Your code with LV 2013 and see, if it works?

 

 

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I tried it in 2013 and it doesn't work when the write method has the Memory In wried to a reference. I've filed a CAR on the behavior.

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