call external application for electrode impedance measurements

[Kabanga]

Hello everyone

I got stuck with that problem for weeks and I hope somebody will help here.
I'm using Labview (8.2) to call an application named ZPlot.

The node "StartSweep"  starts the application and it runs just one time (I mean one sweep of about 61 points) and the measurement data are saved one file.

What I'm trying to achieve is:  the user should be able to set (from Front Panel) how many sweeps the application have to do. I've tried to use the node "GetPointsRemaining" (it returns "0" after one sweep is finished) to restart the application but it's not working. What can I do so that the application runs as many sweeps as set (from the Front Panel) by the user ?

I attached the VI that call the application and I would be very greatful if somebody can help me solve that problem

Best regards
Kabanga 

[MikeS81]

Hi Kabanga,

if the function "GetPointsRemaining" returns 0 then it is ok that the while loop ends. Because 0=0 -> true, not true = false -> and your loop condition is set to run if true.

Mike

[Kabanga]

Hi Mike,

thanks for your answer.
Your are right: the while loop ends when one sweep is finished (means, 61 points has been measured).

Now how to restart it again so that it does another sweep automatically? 

So what I want to do is:

1)- Start Labview
2)-Set the number of sweeps 
3)-Call the external application
4)-Do all sweeps
5)-After all sweeps is finished,stop the measurements

Thanks for your help
Kabanga

 I set  the number of sweeps on the Front Panel

[MikeS81]

Hi Kabanga,

do you want something like this? See the attachment with the additional while loop.

Mike

[Kabanga]

Hi Mike,

thank you very much. It's exactly what I want !!!

I tried to put a Case Stucture, so that the application starts when the user hit a button on the Front Panel, but it's not working.
Any other idea how I can start the application by hitting a button on the Front Panel?

Best regards
Kabanga

[MikeS81]

Hi Kabanga,

you could use an Event Structure for that.

Mike

[Kabanga]

Hi Mike

I used an event structure but it's just calling my application once and  I'm having problem  to stop LV by hitting "stop"
What should I change in my code so that my external application is called as many times as the user set it?

Best regards
Kabanga

[MikeS81]

Hi Kabanga,

can you attache your vi?

Mike

[Kabanga]

Hi Mike

here are my VI and a demo version of the application I'm calling using LV.
I cleaned up the VI so that you find it user friendly....there is still a lot to do, but I'm trying first to make it run before care about user interface

Best regards
Kabanga

[MikeS81]

Hi Kabanga,

create an Event for the Stop Button. It helps.

Mike