invalid input parameter when file is being closed

[Daron]

Hi!

I have a new problem !!

Actually, I am using the driver you advised me to use in my program... This works but I'd like to see (creating an indicator in my labview program) when the scanner is closing the channel 1 and when it is closing the channel 2 so that I can use it as a control for my program..

In fact i have already tried to create all the possibly indicators with booleans and so on, but nothing works...

Plz help me!!!

Plz find also enclosed (jpg file) the configuration i wanna use in my labview 8.0 program.

The keithley driver will be used as a sub-vi. I just need channels 1 and 2 for my program cause I use two differents channels for resistance measurement in 2 differents ways and I just wanna the scanner to switch channel when needed thanks to boolean or something like that and depending of the time interval of the closing channel (included in the keithley driver).

I really hope i have been clear enough to be helped, i'm almost finished!!!

Thank you in advance

Daron

[Daron]

Sorry I forgot the enclose to files

Daron

[Dennis_Knutson]

Can you save your VI in version 7.1?

[Daron]

Here is the File saved in previsous version 7.1

Hoping this helps...

Thanks

Daron

[Dennis_Knutson]

I didn't know that what you had posted was the downloaded driver. I could have gotten that myself and I wish I had looked at it before telling you to use it. This driver is very old and is pretty worthless, imho. It has all sorts of problems but the major problem is that it seems to written to only perform a scan. Relay scans are fine if you have a means to determine when a specific relay is open or closed so that you can synchronize your measurements. There may very well be some hardware output of the scanner that can be used but I don't have the instrument nor a manual for one. You would be much better off if you could just issue a command to open or close an individual relay and not perform a scan. What I would recomend you do is to read to manual to see if this is possible. You could then write a simple VI with two inputs. One would be a Boolean to determine whether to open or close a relay and the other input would specify the relay number. Then your main program would be something like Close 1, Measure Inst 1, Open 1, Close 2, Measure Inst 2, Open 2. You might want to look at some other drivers written for relay switches to get an idea. I have used the HP34970 scanner/mux quite a bit and there is a fucntion in that driver called HP34970A Switch that does something like I am describing. If you have an electronic copy of the programming manual or can provide a link to one, I can help you get started.

[Daron]

Thank you Dennis,

I might have missed something,

So f I have well understood, you don't want me to use my scanner to run my program! Is that it? I hope my boss will agree with that!!

Outpout of the scanner there is a HP34401 multimeter, that is all.

My aim is to make voltage and resistance measurement, and exporting them in an Excel file.

But, I wanna have the choice to get either voltage measurement, or resistance one, or both.

And if the case of getting resistance measurement, I wanna have at any moment the choice to get it in 2 different ways :

Either by channel 1 so that the current goes through the scanner card and then can be put in a direction in my sample, or by channel 2, then the current is sent in another direction to my sample (it is just to make some better measurement as for the capacity of my sample which might keep some elecrons during the measurement). And if i choose the both i wanna make and average of the 2 different ways' resistance measurement. That's why I don't see how you want me not to use the scanner. Then how is it possible to send the current in 2 different directions just with the multimeter?

If you can give me an example of what you said about the boolean and the relay number it would be nice.

Anyway, if you need my program which runs not so bad, or if you want just to take a look at it for a better understanding, i can send it to you.

Really THANKS for your Help, you are my only Hope

Daron

[Dennis_Knutson]

No, I want you to use the relay scanner but I think it would be easier if you don't use it in automatic scan mode. What the driver appears to do is set up an automatic scan where one relay is closed, then opened, then the next relay is closed, opened, then next. etc. at some fixed interval. The problem with this approach is that there has to be some mechanism between the relay scanner and the 34401 to tell the 34401 to take a measurement. Without this mechanism, when you command the 34401 to take a reading, you do not know which relay is closed. Lacking this synchronization, you might even be taking a reading when relays are open. It's very possible that the scanner does provide some sort of synchronization method but as I said, I don't have the manual to read. If you have the manual, you might be able to determine how this might be done. Instead, what would be easier is if you can command a specific relay to open or close without setting up an automatic scan. Most relay scanners that I have used do have this capability. See if you can command a single relay closure from the scanner's front panel. If you can, then you can do this programatically and synchronization is a non-issue.

The best example that I have used is for the Agilent 34970A which you can download. It too has an automatic scan mode. With this box, it is simple to use because it has an internal DMM and the synchronization is automatic. It also has a manual mode that I use whith external instruments. It has the VI I mentioned that you can look at. The actual commands it sends to the instrument are going to be different of course.

[Daron]

Hi Dennis!!

I finally succeded to run my program

Actually, as no driver was really working concerning the scanner Keithley K-705, I have created two sub-VIs so as to ask the scanner either to open or to close each asked channel. Then I have put those VI's in Flat sequence structures

Thanks for your help

Daron

[Albert.Geven]

Hi Daron

Please use the error in/out connection instead of the flat sequence structure.
It gives you excatly the same sequence only now without those frames.
This is called sequence by wiring and is the preferred method in LabVIEW.

The error cluster gives you the added value that you can decide what to do in case of an error.

[Daron]

Thank you albert,

I didn't expect I could use this technique, it is not too bad

Have fun!!

Daron