DAQmx Base and broken VIs

[MogaRaghu]

I recently went in for the NI USB 6008 data logger hardware.

Have been trying to build simple logging applications and for some reason, the DAQmxBase Read VI always gets broken. And there is no way I can  get it back right.

In fact the condition is so bad, now I am unable to run any of  the examples that came on the DAQmxBase 1.4 CD. As soon I got the CD they were working fine.

I am attaching the code that refuses to compile herewith. Will be happy to get some solutions to sort out the mess.

I am on Win_XP Pro + LV 7.1 + NIDAQmx Base 1.4

Thanks

Raghunathan

[johnsold]

Raghunathan,

Your VI is OK on my Mac with DAQmx base 1.5. I cannot run it because I have no hardware devices, but the VI is not broken. It may be that your VI has become corrupted. Have you tried uninstalling DAQmx base and reinstalling it from the CD? Also check to see if there are any updates available for your platform.

Lynn

[e-Cash-Money]

Hello Raghunathan,

The USB 6008 is actually supported by our DAQmx driver v7.5.  Here is an article about using the the USB 6008 with DAQmx and another article on how to configure your device to work with DAQmx.  I highly suggest upgrading your driver and device to get the full functionality of the DAQmx driver.

If you have code that is already written in DAQmx Base, you can use this utility to automatically convert DAQmx Base code into DAQmx code.

Message Edited by E.Lee on 08-11-2005 11:17 AM

[MogaRaghu]

Lynn

Yes .The problem was solved after I re-installed NI-DAQmx Base 1.4. Thanks.

E.Lee

I have seen all the links given by you and it appears that migrating to NI-DAQmx7.5 is really the answer instead of grappling with two sets of drivers for USB6008 and the regular M-Series cards which we use. Also V7.5 seems to have support for VB - something that I have been wanting with to use on M-Series cards. Thanks for the suggestions.

But the V7.5 seems to be a huge download ( 404 Mb - too large even for my DSL line ) . I think I will ask the NI local office to give a  copy on CD.

The other thing that baffles me is the number of components that load when opeining any VI done with NI_DAQmx Base 1.4 . Even a simple  single channel analog acquistion loads something like 700 components  !!   The NIDAQ mx  regular will load just about 200 components. Maybe the USB devices have everything done from the PC end  and hence  the  excessive loading of components.  With memory costs  coming down, the motivation to develop killer applications that are also "slim -n-mean " seems to have vanished. More is merrier for a change.

Raghunathan

[MogaRaghu]

Yes your suggestion worked. Reinstalling the  NIDAQmx  Base 1.4 solved the problem.

And just for the benefit of  others, the following is the chronology of events :

- Have an application coded in NIDAQmx7.3.
- Want to convert to NIDAQmx  Base 1.4.
- Simply opened the 7.3 code and replaced the polymorphic VIs (  Create task, Start Task, Read Analog , Stop and Clear  ) with Polymorphic VIs from the Base1.4 palette.
- Thats it - there was some error and  the read polymorphic VI got corrupted. Unfortanately I also Saved the code when exiting and thereafter no Base 1.4 VI that had a DAQmx Read function in it worked.

Moral : When converting form DAQmx to DAQmx Base, do not replace polymorphic VIs. Delete and wire in fresh BASE VIs .


Not saying that this is the reason. But this possibly could be a reason till I get to know the real reason .

Raghunathan

[MogaRaghu]

I had deduced a moral based on some initial findings :

When converting form DAQmx to DAQmx Base, do not replace polymorphic VIs. Delete and wire in fresh BASE VIs .

But I am sorry,  my deduced moral was wrong. 

The real reason was due to the presence of a Write JPEG.vi in the code that i had written. Get more details on the problem here :

http://forums.ni.com/ni/board/message?board.id=170&message.id=137109#M137109

Raghunathan