using keithley 2400 to measure I-V curve but can not output the data

[echhoo]

Hi,

I found the keithley 2400 driver for measuring the I-V curve, and I hope I can display and record the data. In the driver, I can add a "graph chart" to display the curren after the "setup DCV" finishing, and I can also record the data in PC, but the problem is in the file(like data.txt) only record one data. I try to use the For loop, it can record many data, but these data are the same. The attachments are the original driver and modified driver by myself. Would someone help me? Thank you very much.

[Dennis_Knutson]

That for loop is just silly. All that is does is create an array with 100 identical elements so of course that is what you see in the file. I think your problem is that you just need to set the file position before doing the write.

For portability, you should be using the VISA functions. I'm also curious why you felt you had to write the instrument code from scratch when there was a driver available.

Message Edited by Dennis Knutson on 10-05-2009 09:14 AM

[echhoo]

Hello, Dennis,

Thanks a lot for answering my question. I don't know how to use the VISA function. I had found some Keithley 24xx driver, but I don't know why these driver cannot work?(when I open the driver, the grogram show a yellow !). I'm totally a freshman of Labview and this is also my first experience to use Keithley device. I remodified the IV measurement program. and this time, it can record the all the data. But still has a problem, when I click " turn off", grogram does not stop, unless I click the stop item in the main menu. I think this is because I did not connect the "output error". Though this remodified program can work, it not very good.

Can you help me again? About how to use the Keithley 24xx driver I download. I attach the remodified program and the Keithley 24xx driver.

[Dennis_Knutson]

Neither the first VI or the second has a control called "turn off".

As far as the project style driver, you should install it to the correct location - under linstr.lib. Example programs wiil be found in Help>Find Examples>Hardware Input and Output>Instrument Drivers>LabVIEW Plug and Play. Links on the Instrument Driver Network explain what a driver is and how to use one.

[echhoo]

Hi, Dennis,

Sorry, the "turn off" icon, actually is "Outp ON" or "Outp Off".

I try to learn something in the website address you give me.

Thanks again.

[Dennis_Knutson]

Why would you think the Outp On/Off button would stop the VI? Look at the event for it. It turns the output of the Keithley on or off.

p.s. The event for the button has some Rube goldberg code. Wiring the NewVal to a comparator instead of directly to the case statement is silly. For that matter, wiring from the NewVal instead of the terminal is just as silly.

Message Edited by Dennis Knutson on 10-06-2009 10:55 AM

[billko]

---

Dennis Knutson wrote:

Why would you think the Outp On/Off button would stop the VI? Look at the event for it. It turns the output of the Keithley on or off.

p.s. The event for the button has some Rube goldberg code. Wiring the NewVal to a comparator instead of directly to the case statement is silly. For that matter, wiring from the NewVal instead of the terminal is just as silly.

Message Edited by Dennis Knutson on 10-06-2009 10:55 AM

---

It's just a silly kind of day, huh?  😄