How can I get a smooth (distortions) PWM signal from NI 9476 using FPGA in cRIO?

[auree123]

Can you please look into the first attachment and suggest how can I bind a sub VI which is made as typedef, in host VI? I wanted to implement few sub VIs (built in) to acquire waveform in real time VI.

By searching, what I found is that labview 2010 does not support this feature. Then, how can I utilize those sub VIs in my program?

Also,

My implementation of FIFO in the ways (attached) in FPGA and REal time VI is not giving data in real time when I run it.

Can you suggest me more?

Thank You.

[auree123]

This attachment is aboput typedef file. I am clueless how to hook it for FPGA reference in host VI using labview 2010.

[smithd]

Hey Auree,

That broken arrow is due to the fact that you do not have an FPGA bitfile in your open fpga vi reference. You seem to be using the example, in which case you may want to open the PDF located both in your project view and here:

\Program Files\National Instruments\LabVIEW 2010\user.lib\cRIO Wfm\_exampleProjects

One extremely key point is that you must have a Stop button in your FPGA vi. Not a "stop" button, but a "Stop" button. Capitalization matters. If you are using the example, this will not effect you, but it is worth pointing out.

By the way, are you using this example set for your code?

http://zone.ni.com/devzone/cda/tut/p/id/5963

A colleague sent me the link and I thought I would forward it along. It looks good.

Thanks,

[auree123]

Hi D. Smith,

I am concerned, for now, mostly about those typedef sub VIs like one I posted before. How to bind/show FPGA VI refernce in host side. Because the two Dynamic references for the FPGA and sub VI are different (One is used in the type-def sub VI, which is used only in real time VI, and the other for my FPGA VI).

I found in NI webpage that, Labview 2010 does not support using this typedef sub-VIs in host. Is it true?

For your conveniences I am attaching two relevant links: 

http://zone.ni.com/devzone/cda/epd/p/id/6206---> This is from where I got the idea to use waveform acquisition VI in host VI for data acquisition purposes.

http://digital.ni.com/public.nsf/allkb/43D6024A5307137D862576B1007C20FD?OpenDocument

--> This is one NI link for solution to get around the problem I was facing using the waveform acquision VIs, which are typedef VIs.

[smithd]

Hi Auree,

I'm not sure I understand your concern. That KB you linked is only for versions of labview PRIOR to 2010. 2010 introduced the dynamic mode for FPGA VI references, so you no longer need to bind a reference to a typedef as described there. All you have to do is make sure that the VI reference has the same controls and indicators as what the subVI is expecting. This is why I mentioned that the FPGA VI you open a reference to must have a button titled "Stop", rather than "stop".

Let me know if this does not address your concerns.

Thanks,