ni-visa tektronix tds3054b via tcpip

[sclge]

Its been a battle trying to communicate with this scope. A year ago I was communicating with it fine through Agilent's VISA package. I have not used it since then until about three weeks ago and could not get it working. The only thing that has changed since then was an upgrade to windows 7 from vista. I began troubleshooting by switching to tek visa, trying a vista machine again, trying another scope, verifying the subnet, turning off the firewall and removing possible network issues by connecting the scope directly to the pc through a switch. All of this has failed. My intentions are to use the visa resource with Matlab. I've contacted matlab support and tek support who have both failed to help as well. The tek guy recommended NI-VISA. After installing it, I was amazed to find that it worked perfectly for a day than randomly stopped working. I've gone through everything over and over and can not figure out what is wrong. I heard the VXI11 server in the 3000 series scopes are a bit buggy but I have a tds3012c on my bench that wont work either. I'm getting desperate to network to this scope. If anyone has any suggestions I'd greatly appreciate it.

Robert  

[Elizabeth_K.]

Robert,

I do not think that there is enough information here to really draw a conclusion. You said that you were able to use it with NI-VISA. I am assuming that means you could get information using serial commands from the scope through Matlab. But now it does not work, did anything change in the system? Generally only one version of 488.2 drivers can be installed on one system at a time, how many different VISA drivers do you have on this one machine?

You might also want to check out these links - VXI-11 and NI-VISA Support and Communicating with Instruments from MATLAB using VISA

Regards,

Elizabeth K. 

National Instruments | Applications Engineer | www.ni.com/support 

[sclge]

Thank you Elizabeth for the reply. There is only ni-visa currently installed on the machine. I used NI MAX to connect to the scope. I then used Matlab's instrument tool box with a Matlab driver for the tds3054b to control the scope. I was just calling functions as I have done over and over and then all of a sudden it stops working, after say hours of successful use. I go into NI MAX to verify the connection but it now fails to create the visa resource.

What I don't understand is that I have used multple scopes, multiple computers and multiple visa packages trying to get something to work. The setup is very straight forword with any of the software I have tried so I can't figure out what is possibly going wrong. If there is any information I can supply you with to possibly resolve this issue please let me know.

[Elizabeth_K.]

I can definitely help you get your scope recognized in MAX. You may find this KnowledgeBase useful - "Scan for Instruments" Fails in Measurement & Automation Explorer. If none of the recommendations apply, or if I am misunderstanding what you mean when MAX fails to create the VISA resource, please reply with more information. How is the scope connected to the computer? What steps are you taking to get this error? What is the wording of the error?

Regards,

Elizabeth K.

National Instruments | Applications Engineer | www.ni.com/support 

[sclge]

I didn't find the KnowledgeBase solution helpful. Here are the steps and details of the setup I'm working with. 

- the scope and computer are connected by ethernet to the campus network, both are on the same subnet

- i can connect the scope and pc directly through a switch but i don't believe the network is an issue

- i can succesful ping the device as well as access the scope homepage via internet explorer

- windows firewall is off

- open MAX, Create new VISA TCP/IP Resource, Manual Entry of LAN Instrument

- I enter the IP address of the scope and then Click Validate which responds with the following Error

Could not open a VISA session to "TCPIP0::xxx.xxx.x.xxx::INSTR".

VISA error code 0xBFFF0079

The protocol specified is invalid. 

I hope this helps. Thanks again.

Robert

[Elizabeth_K.]

Robert,

That is all very useful information. I have not been able to find something specific that may solve your problem, but I have a few suggestions for you.

- Since we know that NI-VISA did work at one time, you may consider doing a repair of NI-VISA to make sure that the driver is currently installed correctly. You can find more information on doing that here (How Do I Uninstall or Repair National Instruments Software?). You will want to make sure you select NI-VISA, and that you have the files/disk you installed it from available. If you do not have the files available currently, you may can download them from ni.com/drivers and searching, or by going here.

- Since this is a TCP/IP resource, you could look into creating a wireshark capture to see exactly what messages are being sent from your computer to your scope. This will provide more insight into why the VISA session could not be opened. Wireshark is free network analyzer tool, and can be downloaded here. 

- This may be a long shot, but ther could be something wrong with MAX. You could try repairing MAX, or going through the MAX Database Corruption process. (How Do I Uninstall or Repair National Instruments Software?). I do not think that this is the issue, but if you are looking for things to try, you may want to try that.

Please let me know if any of these suggestions work.

Regards,

Elizabeth K. 

National Instruments | Applications Engineer | www.ni.com/support 

[sclge]

Both NI-VISA have been repaired which has failed to resolve the issue.

I have limited experience working with wireshark or even being able to tell what I'm looking at. I beleive I can get as far as capturing the stream traffic. Would it be helpful if I email the captured files to you? I can capture a file when I try to validate the IP address in MAX and also capture a file when I ping the IP address at the cammand line. It appears that there are constant Header Checksum errors.

Robert  

[smithd]

Hey Robert,

I was only able to locate this NI doc on wireshark, which does not explain errors:

http://zone.ni.com/devzone/cda/tut/p/id/6746

However, on the web I managed to find this: http://www.wireshark.org/faq.html#q11.1 which says you don't need to worry too much about the checksum errors. If you are sure you have the TCP address configured properly, I think we should ignore those errors for now.

To confirm, you are able to communicate with and ping the device normally? Are you able to browse for the device when adding a visa tcp/ip resource, or are you only able to add it manually? Now that you have NI VISA installed, try connecting the device directly to your computer and make sure to check all of your networking settings: http://zone.ni.com/devzone/cda/tut/p/id/3971 and http://zone.ni.com/devzone/cda/tut/p/id/3325 are both decent tutorials for different knowledge levels. If we can communicate with the device when it is hooked up directly, we can at least eliminate networking as a source of problems and move on from there.

Thanks

[sclge]

D Smith,

Thanks for your reply. I don't believe there are any network issues. I can sucessfully ping the device through the command prompt. The device also serves a homepage which I can access through internet explorer. Because I can communicate with the device in this manor I assumed there shouldn't be any problems communicating to the device through its VXI-11 server using MAX. I can't browser for the device nor manually add it in MAX. When I first starting using MAX, the setup worked perfectly. The same day while I was communicating with the device in Matlab it randomly stops working. I then try to add the device manually through MAX again which now continually fails and hasn't worked since. I looked at the tutorials you suggested, the one with the cross over cable I tried several times even before posting to this forum. I didn't use a cross over cable but a standalone switch instead. I can go back to this setup if you suggest but as of now the PC and scope both remain on the school's network.

This is becoming very frustrating. I'm desperately trying to avoid collecting data by hand when I rather run a script through Matlab and have all the processing done automatically. I believe its a rather simple setup which I'm sure others have no problem with which is also why I'm shocked I can't get it working with everything I have tried. I truely appreciate the help though.

Robert 

[slele]

Hello,

I have a very similar problem with a difference that I am trying to connect my PC with the DSA70404B Tektronix Oscilloscope.

I am using a ethernet cross cable between the 2 and I get the error 0xBFFF0011. VI_ERROR_RSRC_NFOUND when I try to open the VISA session.

Were you able to solve your problem? I am really stuck and would appreciate any suggestion.

Thanks.

Sneha