2001 TCSCAN

[nitad54448]

Hello,
I am a newbie so please be gentle I am looking for a VI (with VISA) to close a specific channel in a TCSCAN-2001 card which is connected with a KE2000 DMM (or 2001 DMM) and then measure the DC signal.
Now I am doing this by ROUT:CLOS etc then read the signal but I get,  now and then, an Error 6 in labview. I am using Labview 7.1.
Thanks a lot,
 

[Dennis_Knutson]

The command is correct. Are you using this driver or did you write everything yourself? Error 6 can be either a LabVIEW generic file I/O error or GPIB I/O operation aborted. Assuming you get the error when doing GPIB, then it could be caused by dataflow problems. If you start a read from the instrument and then do a write to it before the read finishes, that could cause the error. If you are not using the driver, I would recomend that you try that and make sure you are connecting the error in/error out clusters to enforce dataflow. You could also post your program for someone to look at.

[nitad54448]

hi,
thanks for the message. the error message is something like "6 : Labview file error" and it takes place from time to time (i figure that either I am trying to read too fast or some initialisation is wrong). but I will use the IVI drivers and I hope it will be better. I will let you know.
thanks a lot, best regards
N

PS. I forgot to mention : I wrote all commands by myself with GPIB send and Keithley scpi book (that's why it doesnt work 🙂

Message Edité par nitad54448 le 06-19-2007 03:51 PM

[Dennis_Knutson]

The exact message should be:

Possible reason(s):

LabVIEW:  Generic file I/O error.
=========================
NI-488:  I/O operation aborted.

You have two possible reasons and the second one would apply. Also, the driver I mentioned is not IVI but a native LabVIEW driver. The driver also uses VISA instead of the lower level GPIB functions (this is a good thing) and if you get an error from VISA, it won't have two possible reasons.

[nitad54448]

yes, you are correct (that's the message); now I am at home and I forgot the exact words but that's it. Sorry for bothering but I don't understand your remark : is it good to use GPIB or is better with VISA ?
N

[Dennis_Knutson]

VISA is a higher level api than GPIB. VISA supports GPIB, serial, Ethernet, USB, VXI, PCI, and PXI. Some instruments are available with different communication options. When you write a driver with VISA, the same driver can be used for all options with little or no modification. A person writing with VISA only has to learn a single api instead of different low level functions such as GPIB, TCP/IP, etc. Also, VISA is more portable to different hardware. When you use the GPIB functions in LabVIEW, you have to use an NI GPIB controller. While I'm not sure why you would want to, with VISA, you can use a GPIB board from any vendor that provides a VISA driver for their board. Instead of a string control for a GPIB address, with VISA you use a VISA Resource Name control. You can click on this control and pick from a list of available resources. You can assign an alias to a VISA resource. For example, if you have a meter at address 5, instead of GPIB0::5::INSTR as the resource name, you can give it an alias of 'DMM'. I find this very handy in systems with a lot of instruments and I can't keep track of the different addresses assigned.

There are a few functions that are not available with VISA and are with the GPIB functions but these are seldom used. I haven't used the GPIB functions in many years except for some really old instruments.

[nitad54448]

hi, sorry to bother you again. I downloaded the drivers and I still have problems with my Ke2000 DMM.
I get Error -213 (Init ignored) and the DMM list SRQ and hangs. any clues ?
thanks a lot

[Dennis_Knutson]

Well, except for the error query, you aren't using the functions in the driver. I would recomend that you first try one of the shipping examples like ke2000 Read Single Example and see if that runs without error. If that does, add the function ke2000 Configure Route Single to it. I no longer have a ke2000 or manual. Is this code the only thing you are running for the meter? A Read? doesn't usually initiate a measurement. How are you triggering the meter? You might also want ot look at the shipping examples to see how the service request is being setup and handled.

[nitad54448]

hi
I tried again as you suggested, with the Ke2000ReadSingleExample.vi from NI website. It works fine when I run this. However, when I change the number of power line cycles to a higher value (2 or 5) there is a -410 ERROR and the DMM hangs with a SRQ signal displayed. I figure that the trigger is taking place to soon so I need to add a time delay somewhere. The point is how big is the time delay related to the number of power line cycles integration. I want to control the integration time at the run time. Are there any other exemples than this one ?
thanks a lot,
N
I attached the vi here just in case

[nitad54448]

hi again
I have, finally managed to make it work... Thanks for the advice. I have now another problem : I got a Keithley 2001 DMM and I would like to replace the 2000 DMM; however for the Keithley 2001 I can not find proper (VISA) drivers. Do you know -or any other gurus around here- where can I find them ? I am using the LV7.1 and on the Keithley's webpage, the drivers for the 7.1 are with GPIB address.
thanks again
regards