Need solution for error VISA: (Hex 0xBFFF0072) The resource is valid, but VISA cannot currently access it.

[neteeshdon]

Hello I m using a USB device for my project. The connected device name appears in MAX device tree. when i started programming in labview7.1, error occurred as VISA: (Hex 0xBFFF0072) The resource is valid, but VISA cannot currently access it. Can anybody help me in removing this error.

[Dennis_Knutson]

Make sure nothing else is open that is accessing the port. That would include MAX.

[neteeshdon]

i succesfully removed previous error with your help but now facing other BFFF0030 timeout occured before operation. Can anybody plz help

[crossrulz]

That typically means either you have a configuration wrong or the device just isn't responding.  Need a lot more details if you want any more help than that.

[neteeshdon]

I am mentioning steps that i am following- 1. Connect my hardware device ADAM 4022T using a A-A cable here i also use RS 485 to USB converter. 2. Open MAX check in device tree and click on my device then set all attributes same as that shown in device manager. Next i click on validate. 3. Then open VISA INERACTIVE CONTROL and write command *IDN\n then click on execute now go to read and click on execute but in return status i got BFFF0030 which is error code. 4. I also try in labview7.1 where i write following attached program and select COM3 as resource where i have configured my device and click on run button again it gives same error i.e. timeout occurred before execution. Thank you for your help.

[Dennis_Knutson]

Did you actually find *IDN? in the Adam manual? You just can't make up commands to send and expect a response. The command is just a default string for MAX and is unique to instruments that complies with the IEEE-488.2 standard. The Adam is not even close to that.

Also, it does not make any sense to set the com parameters to match what is in device manager. You need to set the parameters to match the device you wish to communicate with. MAX and device manager just show the pc side of the link. Please take the time to take some basic tutorials on instrument communication.

[Dennis_Knutson]

From your previous post, I told you about the modbus driver. You did not mention you were using an obsolete version of LabVIEW. Since you are such a beginner, you will have some difficulty in implementing the modbus protocol on your own. I highly recommend that you upgrade LabVIEW and save yourself weeks of time.

[neteeshdon]

I go through some tutorials. Can anybody tell simple step to configure Adam 4022 T using visa interactive control

[nyc_(is_out_of_here)]

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@Dennis_Knutson wrote:
From your previous post, I told you about the modbus driver. You did not mention you were using an obsolete version of LabVIEW. Since you are such a beginner, you will have some difficulty in implementing the modbus protocol on your own. I highly recommend that you upgrade LabVIEW and save yourself weeks of time.

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Why would upgrading LabVIEW help him save "weeks of time"?

Is there something better with Modbus drivers in LabVIEW 2014 that isn't available in 7.1?

[Dennis_Knutson]

nyc,

I don't think the latest modbus drivers are available for such an old version. The op has not made a down convert request for them, either. I think the latest use lvoop so they may not be able to be converted. I couldn't find an a 7.1 version of the older modbus drivers, either.

neteeshdon,

Have you studied the modbus protocol?