where does retain wire values store its data

[Ray.R]

In LV8.x, where does "Retain Wire Values" store its data?

Nice new feature in LV8.x...

But has anyone tried it?  If so, where are the retained values?

From what I understand, by selecting this option, it will retain the probed values for a given probe, after the vi ran.  Which means that for a loop, you can see the historical data gathered by the probe... 

It is located to the right of the "Highlight Execution" on the block diagram toolbar.

Unless I misunderstood its purpose..

Thanks,

RayR

Message Edited by JoeLabView on 08-29-2006 04:46 PM

[Darren]

My understanding of the feature is that, when you have it enabled, you can go probe a wire after a VI has finished executing and see what the last value was to pass through that wire.  So to answer your question, the Retain Wire Values feature stores its data in memory.  🙂  I don't believe the feature enables you to see any value that has ever passed through a wire...only the last value.

-D

Message Edited by Darren on 08-29-2006 04:31 PM

[Ray.R]

Thanks Darren,

Let's see if I understood correctly.

You enable that feature, run the vi and it stops normally (for whatever trigger / event/ etc).

You place a probe on the wire after the vi has stopped, and you can see the last value on that wire.

So that means that there are memory locations assigned for practically all the wires within a given vi whose "Retain Wire Values" has been enabled.

Do I understand it correctly?

If that is the cas, it will help to keep probes clean instead of placing several of them while debugging.

My original understanding would be a nice feature for future releases 😉

Thanks Darren,

RayR

[devchander]

Darren,

If a VI is run again, Do its wires reinitialize their values to default at once??

Or will you still see the last value in its previous execution until a new value passes through that wire??

I do not have LabVIEW 8.x installed on my system and hence the query

[parthabe]

same doubt like Dev, sinceI'm using LV7.1

rgds,
Partha.

[TCPlomp]

It will keep the values from the previous run so be carefull about this and make sure the code has executed when you probe it afterwards.
I tested it with this:

Where in the first run the 'Boolean' was true and thus a probe befor 'OK Button 2' was true.
The second run 'Boolean' was false and the 'wire' stayed true. This is expected since 'OK Button 2' stays true as well. After some coding the value is resetted to false, while 'OK Button 2' stays true

Ton

Message Edited by TonP on 08-30-2006 12:28 PM

[devchander]

Oh, that can become a concern while probing!