Converting old VI's to work with new cRIO's

[BenCox]

So, I've been trying to convert old, working VI's using cRIO 9012's, to work with replacement cRIO 9056's.

Everything is going well, I've managed to get control over most of the variables (many of the variables control pneumatic valves for the process we are doing, and they all receive signal and react appropriately).

My issue falls with an aspect of the 9012's that I don't think is available on the 9056's.

As a safety measure, in case the computer loses connection somehow with the cRIO and therefore the process, the VI is set to run a subroutine which turns various numbers of the aforementioned pneumatic valves, failing the system to a safe position.

The previous person (who is unavailable for comment, unfortunately) who designed this function hinged this safety on actuation of the LED variable on the 9012's, if it pinged the cRIO and saw that the LED hadn't changed, it indicated a failure to communicate, and after a set amount of time it went into the failsafe mode.

I've upgraded the cRIO and got it communicating, but this LED variable has been a pain to sidestep. It is deeply entrenched in the existing VI's, simply removing it breaks most of the project. Is there a way to replicate this on the 9056 that I'm just not seeing? Or is there some other way that I might be able to accomplish something similar without reworking a ~30 VI deep project?

[GerdW]

Hi Ben,

when you have problems with your code then you should attach that code!

How should we know about your VIs and "variables" (whatever they might be)? How does a variable "ping" a cRIO? How does a variable "see" it doesn't change?

[BenCox]

Hi!

I guess the problem isn't necessarily with the code, per se. I'm asking about the available variables within the cRIO itself. The 9012 allowed manipulation of the LED from the code. Is this available on the 9056? If not, is there a similar function available for use on the 9056?

I'll see if I can't screenshot the wiring diagram for the 'safety watchdog' as it was labelled (I apologize I don't have one currently, it's been a long day), but in a nutshell it inquires about the status of the LED, toggles the LED on the cRIO on/off, waits for a set amount of ms, and then inquires about the status of the LED again. If they mismatch, then it deems a connection issue. Multiple failures and it enters the failsafe mode. This code works on the other 9012's we have, it's identical.

Since the code attempted to modify the LED and was unable to, it enters the error state immediately. If I could swap that out with some other boolean variable on the 9056, that would solve my problems right away. If I could search the cRIO for available variables, that wouldn't be the shortcut I was looking for but it would be a step on the road to solving the problem.

[BenCox]

A screenshot of the aforementioned 'watchdog' VI.

[GerdW]

Hi Ben,

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@BenCox wrote:

in a nutshell it inquires about the status of the LED, toggles the LED on the cRIO on/off, waits for a set amount of ms, and then inquires about the status of the LED again. If they mismatch, then it deems a connection issue. 

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Where does that code inquire the LED state? All it does is to set the value of a shared variable...

On which target is that code executed?

[rolfk]

Your issue is that your program writes to a shared variable that does in itself nothing. There needs to be some shared variable server that will respond to this. Most likely on your Windows machine. But with the information you have provided so far it is fairly difficult to know what your setup really does. We would need to have a look at the actual code and project to say more about it.