usb-6008 crashes

[floresma]

Hello,

My USB-6008 OEM card crashes after approximately 6 runs of my test.  In order for it to work again I have to unplug the USB cable...  I have it connected to a USB hub that has a seperate power supply.  This seems to help a bit.

Does anyone know what can be done to correct this from happening?

Thanks,

[crossrulz]

Care to share your code?  One of the things that could possibly be causing this is not cleaning up your DAQmx tasks.

[GerdW]

Hi floresma,

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I have it connected to a USB hub that has a seperate power supply.  This seems to help a bit.

---

I had a similar problem with an "in-box" NI6008: when you draw too much current over some of the in/out pins the 6008 needs a cold start (aka USB unplug/re-plug) to work properly again. (It didn't report an error as long as the DAQmx task is running, but on restart of the DAQmx task the 6008 isn't available anymore.)

Could you check all your I/O pins for shortcuts or low impedance shunts?

[floresma]

Here's my code.

[crossrulz]

You really should clear out your tasks in your cleanup state.  But I think GerdW is on the right track.  You likely have a condition where you are drawing too much current.  The DIO can only drive 8.5mA, 102mA total.  I know the current ratings are a little higher using the external power supply than using the USB power.  So you really should make sure you are not on the edge of how much current you are drawing.  Adding buffer circuits to the DIO should help.

[floresma]

I checked my circuit.  There are no shorts, or low impedance shunts...

[wilburwu]

Hi 

This is a known problem with the NI USB devices. I don't understand why there is till today not a official solution from NI !?

What do you mean by "crashes"? The problem I have is the USB device does not exist any more in the system hardware list. As a result, you have to unplug the USB cable and plug in again... And this is really annoying!

You may restart the USB device programmatically: https://decibel.ni.com/content/docs/DOC-22660 And also I wrote in the command that you may use another way to make it more smoothly (devcon64 restart *PID_729B*).

I remember that the problem because of the bad USB structure of the computer. Most of the laptops don't do this well. So the solution with devcon is the one I have. 

[fgrootent]

I had same problem for me this solution worked, in the initialization fase I added the following DAQmx channel property: Analog Input ->General Properties->Advanced->Data transfer and memory->USB Transfer Request count and set the property to 1

[floresma]

Hi,

I tried this method, but it only seems to run on XP.  Do you know what the command lines would be for windows 7?

Thanks,

[floresma]

Hi,

How did you configure your DAQmx chanels?

Thanks,