Reentrant Boolean Array Controlled stopwatch SubVI

[mhaque]

I am in the final stages of implementing my program.

Currently I have to overcome two obstacles .

#1 corresponds to the attached VI "My stopwatch"

The round LED starts counting the time and stops it. Problem is even if I turn it off it, the timer keeps counting the seconds when I turn it on again. I want it to accumulate only the time it spent in the on position. How do I do this?

#2 corresponds to the VI "array of time".

I want to use "My stopwatch" as a reentrant subVI in this VI. I want the round LED Boolean array as the control to switch the stopwatch on and off.

Thanks for all your help.

mhaque

[JÞB]

Check out the CLD exam example solutions.

One of them for the Car-Wash includes a modification of the "Elapsed timer function" that add a "Pause"

[altenbach]

On a sidenote, have you ever wondered what would happen if you would remove the "equals true?" and wire straight from the terminal to the rest of the code? 😄

(see also)

[mhaque]

aaaaaaaaaah so its pointless having the equals to sign.

I was just using someone elses code.

Thanks for clarfification.

mhaque

[JÞB]

We just call that WEC.   or Wire Equivalent Code

[mhaque]

I have managed to modify an existing VI to do what I want i.e. have one start/pause Boolean control for the stop watch.

Criticisms please. The block diagram looks simple enough.

Also I can't quite get it to reset.

Any suggestions.

Thanks

mhaque

[mhaque]

I have managed to make a Boolean Array controlled stopwatch.

It is within a while loop. My question is how do I use this VI as a SubVI? How do I overcome the while loop?

I found this thread

http://forums.ni.com/t5/LabVIEW/handling-while-loop-in-subvi/m-p/1117918

but since I am new to LabVIEW I do not understand how they got over the issue using the VI server reference and Value Change Property node.

They use references but I don't understand how the reference controls tie in with the coding.

Your help is much appreciated.

mhaque

[altenbach · Accepted solution]

To use it as a subVI, it is easiest to use globally initialized feedback nodes. Here's a quick example.

(Place both VIs in the same folder, then run CallTimerSubVI)

You are using way too much code. Please rethink what you did! Also study my example.

• Instead of 24 shift registers use three, containing arrays of 8 elements (or the number of timers you need).
• You need a resolution of one second, so place a wait inside the loop. There is no need to spin it 10 million times per second, you are just wasting cpu cycles and starving all other programs.
• One diagram constant of 1000 is sufficient (instead of 16!). You can branch the wire.
• Why divide both values by 1000, then add? Add first and divide once!
• Why invert the booleans, just swap the cases if needed?
• (Even if you really want to invert all booleans, do it once on the array side.)
• This is a small VI, why maximize to the screen?
• Note that my code scales well. A few minor changes would allow it to be used with 100 timers. To do the same with your program design would be impossible. 😄

[mhaque]

How long did it take you to get this good? Seriously?

It works perfectly! wow!

[mhaque]

Shoot I meant to reply to this post instead of

http://forums.ni.com/t5/LabVIEW/Can-LabVIEW-pickup-from-where-it-left-off/m-p/1334910#M542745

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Hey altenbach

Where does the VI initialize, i.e from where are the zero filled arrays created.

I want to place a read/write binary file and I am wondering where I should wire it to, to save the timers when I exit the program.

Otherwise the timer starts from 0 which is not what I want.

Thanks

mhaque

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Since you solved both problems I hope this is not too much of an inconvenience.