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Best way to implement confirm button in conjunction with menu ring selections

So basically I have a series of menu rings that implement different cases of a structure that adjusts PWMs and other timing signals.  I have received a request to add in a confirmation button/dialog that pops up to make sure the operator wants to perform the selected operation.  I'm doing this on a PXI 7831R FPGA board and have run into timing violations in the past, so the less timing critical, the better.  If there is some way to offload this onto the host VI, even better.  Thanks in advance for the help.
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Hi,

 

Ever thought about creating a VI containing a button with an Event Structure simply waiting for a value change event?

You can modify the VIs appearance under the VI Properties (Ctrl+I)

 

 

Christian

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If there is some way to offload this onto the host VI, even better.

 

Considering the FPGA does not support dialogue boxes or event structures, you will have to implement this into a host VI.

 

My suggestion? Have a case structure with a latch boolean control on it (ie. update config). Your host VI will have an Open FPGA VI reference and run the FPGA this way. When you want to update the config, you can change your items, then hit 'update'. Include the dialogue box for confirmation if you wish. When this is done, it will use a read/write control to update the boolean 'update config' on the FPGA. Your FPGA VI will then read that case structure with the config data in it once(since it is a latched boolean) and then continue on its merry way.

Rob K
Measurements Mechanical Engineer (C-Series, USB X-Series)
National Instruments
CompactRIO Developers Guide
CompactRIO Out of the Box Video
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For sure, the Event Structure hast to be in the Host.vi. I would never create an FPGA Application without a Host.vi.

 

If you need a UserInterface you will need Graphs and other Controls which wouldn't be necessary on a FPGA VIs Frontpanel for simple interfacing. And you would not place a Graph Control or something similar on a FPGA VIs FP, this is really the wrong place.

 

So if a User needs to change settings, you need a Host.vi and you can use a event-based design, whatever the communication in the background between FPGA and Host looks like then. Robobs suggestion would be one possible method to exchange the settings, though you can also think about interupts.

 

 

Christian

Message Edited by Christian_M on 11-24-2009 02:05 AM
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I do have a host VI and have had one.  All I needed to know was 1.) The best way to implement this one function and 2.)If it could be done on the host VI.

 

You guys have answered my questions and I simply need to play around with it for a bit to get it to work right.

 

In response to Rob, you're saying I put the Open FPGA reference in a case statement w/ a latching boolean control??  I'm not exactly sure how that would work.  If you could, please clarify.  Thanks!

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