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Can I put a READ function in a TRUE/FALSE case structure?

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Hi,

 

I have a vi that operates as controller for a mechanical system of motors.  There are several sensors of various types, that provide input to the vi, including encoders, whose period is being measured.  The attached vi is the encoder period measuring part. It measures 15 periods and tells me the average of the 15 with each loop iteration.

 

In my application, the encoder period measurement is not needed unless the vi knows that ALL THE OTHER sensors in the hardware configuration are measuring values within the desired range.  For example, Sensors A, B and C should all measure between 5-10.  If they are all showing values between 5-10, then, we want the encoder value to read and display.  If only one of the sensors, say A, is measuring 12, then, we don't want the period value to READ or be subsequently processed.  So, it is easy to set up the sensors A, B, C, to give a TRUE or FALSE based on whether they are within range or not, and if all 3 are TRUE, then, that value can easily be passed to the case structure that holds my READ function for the period.  Is this a good way to do this?  The goal is to eliminate unnecessary execution time that the period READ function would consume, as well as all subsequent calculations that are performed on the period value collected.  The period data is of no use if any one of the other sensors is not in the correct range.

 

If any one of the other sensors is out of range, we want to skip the encoder READ step altogether.  So, it is easy to structure a BOOLEAN in my vi as shown in the attachment.  If I do it this way, will it throw an error, or just skip the READ until the BOOLEAN is true again?  Is there a better way to prevent the READ from happening if one of my other sensor values is not within the correct range?

 

Thanks,

Dave

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Solution
Accepted by topic author dav2010

Sure, you can put a Read inside a case structure. For your application, just check that your sensors are all within range (Comparisons palette), then AND the T/F's and use the result of that for your case structure. (If you are already doing the in-range check, I can't see it here because you have 5 subVIs that I cannot open here.

 

Cameron

 

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