USB devices block my Labview Program

[JuanPablodelvalle]

Dear All

I have a problem , I have and acquisition system working in a VXI frame connecting to a computer using USB , actually we update the operating system and install Windows 7 ( previous was xp ) with the new O.S we have in some cases that problem:

                 When I plug in some USB devices automatically my labview program is blocked.. , for example if I use some USB keyboards , USB modem etc..

                 I can understand that is a problem related with the O.S  , but I can't find any solution to overcame it , only avoid to plug in such device but the problem is that I can't test completely all the possibilities to avoid the problem...

I hope some of you have a smart idea about that..

Thank you very much.

[Norbert_B]

What do you do in your application? Do you communicate with USB devices? If so, what interface are you using (e.g. VISA)?

Can you pindown the effect to specific function(s)?

Norbert

[JuanPablodelvalle]

Yes I communicate with the VXI rack using USB . The complete application is block in the memory , the funny thing is that the same software version working in other computers don't have  such problems  , this is because I think could be related with the operating system installation .. I'm looking for is a way to give to the LabView program the highest priority in the memory ..

[Ranjeet_Singh]

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@JuanPablodelvalle wrote:

Dear All

I have a problem , I have and acquisition system working in a VXI frame connecting to a computer using USB , actually we update the operating system and install Windows 7 ( previous was xp ) with the new O.S we have in some cases that problem:

                 When I plug in some USB devices automatically my labview program is blocked.. , for example if I use some USB keyboards , USB modem etc..

                 I can understand that is a problem related with the O.S  , but I can't find any solution to overcame it , only avoid to plug in such device but the problem is that I can't test completely all the possibilities to avoid the problem...

I hope some of you have a smart idea about that..

Thank you very much.

---

I dont think because of USB it is posing problem. May be USB is frezzing the OS itself. If the LV program is not running then also is it happening?

[JuanPablodelvalle]

No , I don't think so , normally there is no problem apart of the frozen L.V app , and even I have a green Led that test the communication between the VXI rack and the computer and it is blinking ... but the L.V user interface is completely hanging up.. and is not possible to remove from the memory..

[Norbert_B]

First, you didn't really answer my question if the hang of the LV application is connected to actual USB communication.

It seems to me that you try to access USB hardware in your LV application, but if during that access USB devices change, LV hangs. Correct?

How long does it hang? What do you normally to "solve" the hang?

Norbert

[JuanPablodelvalle]

Ok.

The LV app is continuously communicating through USB with rack

There are two ways to block it(LV app):

1. If I conect my usb modem -----> LV app automatically is blocked.

2. if I have a USB keyboard under certain conditions ( more than 7% of the cpu load) if you push a key ---->L.V is blocked

To avoid any problem I do :

Use a PS/2 keyboard

Don't plug any USB device apart of mouse and the USB cable to the VXI rack..

But for me it is not acceptable because I can control what the user can do all the time , I need to make my system more reliable..

Thank you very much!!!

[billko]

I'm with Norbert on this one - how long is it blocked?  Have you tried just waiting?  I would expect that you might have an amount of unresponsiveness due to Windows installing drivers/enabling devices, but it should be all well and good after a few seconds.

And to speak to another issue.  Actually you should have complete control over your tester in that manner.  No one should be able to fool with hardware configs while you are running your tests!!!

[Ranjeet_Singh]

Close all other application and try to run only LV app.

[Norbert_B]

Do you use some kind of USB Hub? If so, does it change if you use generic USB IO from the computer directly?

Norbert