USB-6501 error -50405

[rlepard]

I have an application in which I'm using NI-DAQmx to control 6 USB-6501 devices through a DLink DUB-H7 USB 2.0 hub.  The application has run for approximately 24 hours, during which 4 of the 6 devices worked properly the entire time.  The two devices that I have observed problems with have both returned error number -50405, "No transfer is in progress because the transfer was aborted by the client.  The operation could not be completed as specified."

Of the two devices that exhibit the error, one device errored for several hours, worked for several hours, then errored again without any intervention.  The second device appears to have latched in this error mode and did require intervention to reset it.

I've read other posts and will try to address some of the items others have mentioned:
* my machine is not low on RAM or virtual RAM
* there are no related events in the windows event log

Other symptoms:
1.  The problem device's LED remains off
2.  The problem device is visible in MAX under the NI-DAQmx Devices
3.  The problem device is visible under the Windows Device Manager
3.  The problem device failed self-test (Error -50405)
4.  The problem device failed the Reset Device command (Error -50405)
5.  The problem device did respond correctly after unplugging the device from the hub then plugging it back in

NOTE:  I'm using NI-DAQmx 8.9.0.

What can I do to troubleshoot the problem?

Thanks!

[ColeTrain]

A few things to try would be isolating the problem modules/ports.  Can you open a test panel to them individually?  Can you open a test panel while running the other 4/5 that work?  If you change the ports around is it always the same device/port that fails?  As each of these is bus powered, are the devices getting enough power? 

After all of those, another step would be to install DAQmx 9.0 and see if that alone fixes the issue (doubt it, but maybe) and if it doesn't, DAQmx 9.0 supports Spy captures.  This is a log of all communication going from the computer to your device and that might tell us something from there (and when I say all communication, I mean all. This captures everything from test panels, to LabVIEW code to C calls.)  

[Tom__Sedlack]

You may be having a power supply issue with having all 6 modules connected to the same hub.  Have you run this configuration before or is it new?  Each 6501 "typically" draws 80mA but this can increase if there is external circuitry, such as pull-ups, added to the module.  One thing to try is to monitor the 5V output pin on the 2 trouble modules.  You should use a strip recorder or some other measurement device that will hold the minimum voltage so you don't have to watch it for 24 hours.  The other thing to try is to add another powered hub and split the modules 3-3 to see if that keeps them alive.  I am suspecting it is a voltage problem and the 2 modules are less tolerent then the remaining 4 but they may be right on the edge of failing as well.

Tom

[rlepard]

Thanks for the responses ColeTrain and Tom.  I've been running for 20+ hours without an error, but also without any changes.

Do either of you have any quality USB hubs you would recommend?  Just about everything I see is designed for low cost, consumer applications.

ColeTrain: 

* It is not always the same USB port that is erroring.  I may try swapping ports at some point.

* When I have the error condition, I'll try a test panel

* I've downloaded DAQmx 9.0, but want to make one change at a time to convince myself that I've identified the root cause.

Tom:

* I'm using a scope to monitor the 5V output pin and it looks good so far.

* Under what conditions would the device draw the maximum power (500mA)?  Currently, I have 3 lines configured as output with a total current output of appx 20mA.

Thanks,

Rob

[ColeTrain]

Hello Rob,

I can make a recommendation based on one that I've used at home, but you should be aware that this is not an endorsement from NI and I cannot promise that everything will work with the 6501s you have as I've never tried it.  But here's what I have used at home. It has gotten some good reviews,  is externally powered, and works fairly well.  The only down side is it gets a bit slow when trying to trasfer large amounts of data, but I haven't found much out there that doesn't.  Hope this helps!

[JÞB]

DLink DUB-H7 USB 2.0 hub. 'nuf said

At CCI I have placed these in the do-not-order pile.  They do cause intermittant failures in communication and are (IMHO) ovely susceptable to EMI and ESD.  (don't even touch them with velcro).

I have had better luck with Belkin products in industrial applications.

[rlepard]

I found a few hubs labeled as "industrial" grade.  They might just have shinier cases, different power connectors and more $$, but it can't be any worse that what I'm dealing with now.  Here's one that looks legit that I'm going to try: http://www.moxa.com/product/UPort_404_407.htm .  I'm going to connect it to a SynQor AC-DC supply (already in our application) that will isolate the device from any noise on the AC line.

I should know pretty quickly if this resolves the issues.

-- Rob