DAQ to FPGA

[atokad]

I am trying to convert an old VI from using DAQ to FPGA using user-defined variables and I have no idea how to go about it. I was hoping someone could help because I'm sure I am missing some sort of obvious solution

Attached is a picture of what the DAQ looks like and what the VI looks like

[GerdW]

Hi atokad,

I am trying to convert an old VI from using DAQ to FPGA using user-defined variables

I suggest those steps:

1. Analyze this "old VI using DAQ" and write (on a sheet of paper!), what the VI does and which way it does its work

2. Learn about RT and FPGA programming in LabVIEW

3. Write a NEW FPGA VI and RT VI doing the same stuff as your old VI…

Hints/remarks:

- You cannot use the DAQAssistent or any DAQmx function in a FPGA VI.

- What are "user-defined variables"? Why do you want to use them?

- Which hardware do you want to use?

[atokad]

So I've written a FPGA/RT program before using user defined variables... I know that I cannot use DAQmx functions on the FPGA VI that's why I am trying to switch over to something else, but I don't know what to do. I'm using a cRIO 9035

[GerdW]

Hi atokad,

you didn't answer my questions...

What are"user defined variables"?

Which modules are in your cRIO?

Do you use the ScanEngine or FPGA mode? Or do you use the hybrid mode?

What should your program do?

[atokad]

I don't see how any of those questions are relevant....

I'm just trying to convert what I posted in that DAQ function into something that I can run on a real time VI and send a voltage reading to my FPGA VI

[GerdW]

Hi atokad,

you want to read an analogue input at 12kHz for 5s? Then you need to read the input in the FPGA and stream the data to your RT vi. You will find examples in LabVIEW (create a new RT project)...

Why do you want to send a voltage reading to the FPGA? Usually you get the reading from the FPGA...

You still don't explain the "user defined variables"...

[crossrulz]

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GerdW wrote:

You still don't explain the "user defined variables"...

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Think of Network Published Shared Variables that are writen to OR read from the FPGA (yes, they are uni-directional).

[crossrulz]

I had two projects last year where is was basically "replace this old DAQ system with something modern since the computer died and cannot be replaced".  Both were talking to PLCs over DIO as well.  So I replaced both of them with cRIO-9064.

Reach your channels in a loop on the FPGA and use a DMA FIFO to send the data to the RT.  The RT can then do whatever FFT and spectral analysis from there.  Not sure what else you have in there since you only showed a very small part of the code.