How to pause a vi programmatically (with many loops and cases)

[ASH2020]

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@jwscs wrote:

take what GerdW said to heart

and a queue and an event structure don't make it a producer-consumer-design-pattern, although it uses both of them.

you also have to decouple your measurements from your presentation

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I do take that on board.

I thought I was decoupling by having the plotting in a separate loop.

[jwscs]

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@ASH2020 wrote:

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I thought I was decoupling by having the plotting in a separate loop.

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it should be the other way around 😉 (because for displaying you consume)

[ASH2020]

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@cbutcher wrote:

Some quick comments along the lines of those already posted:

• You can use SubVIs even if you don't know if they're finished/going to be changed. You can always delete them later. If you really want, you can right click on a SubVI and choose to "Replace with SubVI Contents", which will basically copy-paste it out for you (this is almost the inverse of Create SubVI on the Edit menu).
• Reflex 1 and 2 are almost but not quite the same case. It seems to me that you're changing only the stimulus choice between two different wires. You can make one Event Structure case handle both by going to the edit window for the structure, choosing to Add Event, and selecting the second. Then you can use a Select node with the two inputs, and compare the CtrlRef available on the left edge of the Event Structure to get a boolean allowing you to choose between the two at the Select node (compare equality to a reference for one of the buttons).
• Here is the link for the Producer/Consumer design. This might be useful, but maybe you already read it.
• Here is the link for the State Machine tutorial. This might require too much overhauling to be the best way forward at present, I'd say once you modularise with some SubVIs it will be easier to see what you want to do.

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Thank you for the comments.

I had not tried to make sub vis of the main data collection loops because they have so many inputs, the icon pattern seemed to be very complicated, with about 6 inputs.

Not sure I really understand about combining Reflex1 and Reflex2 because they may have different inputs selected on the front panel, Reflex1 may be 105dB and Reflex2 may be 110dB

Thanks for the links, I will definitely look at the State Machine tutorial. It's unfortunately like jumping on a moving bike. When you're thrown in at the deep end, the job is so urgent that you can't stop long enough to learn the right way to do things, even though that is the most efficient way long term.

[jwscs]

regarding the too-many-terminals problem:

use clusters, bundle all the data and have the cluster-type as your input-/output-terminals

[ASH2020]

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@jwscs wrote:

regarding the too-many-terminals problem:

use clusters, bundle all the data and have the cluster-type as your input-/output-terminals

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I did try that but then often, just one of the cluster elements needs to be different according to front panel inputs.

[jwscs]

you could

- define the common properties in one cluster

- define other clusters/variables for the differing properties and create an extra terminal for them

or add a variant data holder in the 1st cluster, which you then have to cast to the correct type inside the subvi

[ASH2020]

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@jwscs wrote:

you could

- define the common properties in one cluster

- define other clusters/variables for the differing properties and create an extra terminal for them

or add a variant data holder in the 1st cluster, which you then have to cast to the correct type inside the subvi

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That's good, thanks. I didn't know about variant data holders.

[billko]

IMHO there is really no excuse for "messiness".  What messiness does in the beginning is make you hopelessly lost as the project grows.  I've had plenty of projects grow from engineering tool to full production applications, and neatness is the only thing that saves you from drowning in your own spittle.

What really helps here is to plan for scalability from the moment you place your first node on the block diagram.  Don't let anyone deter you from this.  If you allow for growth, you don't end up with an unmanageable mess later.

[cbutcher]

It might be worth noting that when you end up with a bunch of clusters and accessing one element here and one element there, a class object might be what you want.

With an object, you can place these data elements in the private data of the class and the method VIs can unbundle and bundle the class wire (use By Name) as needed.

This can really help to clear up busy block diagrams into manageable, 32x32 pixel blocks.

[ASH2020]

I wonder if anyone could explain this. I have taken all your advice and cleaned up my code considerably, also got rid of some of the redundancy.

However, I am at my wits end trying to work out why I can't stop my inner loop with a button. I have now removed my loop and put the simplest random number example in to try and debug it, but it still doesn't work. If I cut and paste the inner while loop into a new vi the button works and stops the loop. However, the stop button doesn't have any effect when the loop is running inside the event structure. Any ideas why?