DO task randomly stops (no errors generated)

[josborne]

Attached is a simple little VI that generates a digital waveform and outputs it to the one of the DO pins.

For this example, it is a 50 kHz digital signal.  If I let this VI run, it will just stop randomly and without any error.

This appears to happen randomly.

I am using LabVIEW 2011 and DAQmx 9.3.5 using a NI-USB-6366.

[josborne]

To elaborate:

The problem is that it stops generating output after a random amount of time.  But the VI doesn't stop executing, nor does it generate an error.

Btw:  This issue appeared to start hapenning when I switched from a USB-6361 to a USB-6366.

[Mcdan]

I did verify that I see a roll over at 4.29 G with USB X Series as well.  I'll give your VI a go and see if I can reproduce the stopping behavior you see.

Dan

Edit: Got threads mixed up.  Roll over is in reference to this.

[josborne]

Just ran the same code on my 6361 and it doesn't seem to freeze up.  Though I should let it run for a longer period of time.

I have a suspicion it only happens on the 6366. 

[nathand]

If you put a wait in the while loop, does it still stop randomly?

[josborne]

Yeah, adding a 100 ms wait to each iteration does not seem to have any effect.

In fact, if you try the attached VI, which outputs a 10 MHz digital signal, my USB-6366 almost immediately freezes up. 

But my USB-6361 doesn't freeze up at all.

[josborne]

Whoops.  My bad.

This error actually DOES occur on both my USB devices:

USB-6351

USB-6366

But does NOT occur on my PCIe device (PCIe-6363).

Am I doing something wrong here?  Can't seem to ouput a 10 MHz signal?

[josborne]

Btw:  I am also getting a similarly strange behaviour on my AI tasks.  Just freeze up and stop returning any data.  I'll see if I can isolate that issue, too.  

[Mcdan]

Can you put a DAQmx Is Task Done.vi in your loop?  I don't necessarily know that reading a write status property would return an error if one were to occur.

Dan

[Ben]

any chance you are running on an old machine with USB version 1 as aposed to USB 2.0 that added... were they pipes?

Ben