error 200077 in audio communication

[Omershah]

Hello everyone,

I am using myDAQ for looping back the audio channels. I am not using the exprees VIs since it is a requirement. But the VI is giving error 200077 with a statement 'Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property'. please help.

[mikeporter]

I am on my phone and can't look at your code, but basically there are two things that could be in play here:

1. All NI DAQ devices don't have the same capabilities. However DAQmx supports all the hardware. This means that you could be setting a property that is available in DAQmx, but which your DAQ hardware doesn't support. If this disparity is causing your problem the documentation on your hardware will tell you what functionality is supported.

2. You could be setting two valid properties, but is a way where they conflict with each other. Again, your hardware documentation will be your guide is sorting out the conflict.

Mike...

[Bob_Schor]

Have you tried doing whatever you are trying to do using MAX's Test Panels?  Your code is curious -- you set up your DAQ for continuous I/O of 100 samples at 1KHz, then proceed to read (or write) a single point.  Notice if you set MAX up for 100 samples at 1KHz and said "Start", you'd get a thousand points/second in "clumps" of 100 at a time (which, of course, is what your code is trying to do ...).

Bob Schor

P.S. -- I couldn't find that error message -- are you sure you got the numbers right?

[Omershah]

With this VI i am just trying to send a signal with a frequency and amplitude and that should be detected at audio input og the same device just to confirm that these ports are working properly.

SInce the audio ports support only signals upto +2  or  -2 thats why i selected 1

But it give error which is i think related to amplitude.
Waiting for your help @Bob_schor

[Bob_Schor · Accepted solution]

You still have not answered my question about the Error Message -- there appears to be no error message with the number 200077.  I do not have a myDAQ in front of me, so I cannot directly test your code and see what the error is, but you can ...

I understand that you want to learn how to use the DAQmx functions directly without using the DAQ Assistant.  This is a worthy goal, since you can do much more, and have much more direct control, when you control the loops and use just the DAQmx functions that you need.  A very powerful tool is the concept of a Task, which you can create in MAX or in the LabVIEW Project.

The LabVIEW Project provides a framework to wrap around your project.  It may not make sense to a LabVIEW Beginner, who writes a single Giant VI (yours isn't that big, don't worry) that takes 3-10 screens to view.  But one very important technique that applies across all programming languages is Divide and Conquer, or Write Subroutines/Functions/Sub-VIs That Do One Thing.  Indeed, all but the most trivial LabVIEW program may involve tens, hundreds, even thousands of VI.  How to manage them?

Before LabVIEW 8, the answer was "Let Windows Do It", meaning place them in Folders and sub-Folders with Helpful Names.  So you might have an all-encompassing top folder called "My Big Project", with sub-folders "Interaction with User", "Interaction with Hardware", and "Data Communication", inside of which were "Type Defs", "Utility VIs", etc.  When LabVIEW Project was introduced, it added the ability to include additional Project-related information, such as "What DAQmx Devices am I using", "How do I want to build an Executable", and "How do I manage code split between two or more Targets" (important in Real-Time and RIO architectures).

There are excellent tutorial materials available on the Web.  One place to start is here, Advanced Programming in DAQmx (there also the main Getting Started with DAQmx page which will point you to the Advanced page).  On the Advanced page, the first article is especially useful.

Notice the concept of a Task, which can be defined both in MAX and in the Project.  Defining a Task handles a lot of the "messy details" in configuring DAQmx, as it binds such things as the Sampling Rate, Channel Choice, type of sample (e.g. Voltage or Temperature or Force), special Scales, etc. into a single thing, the Task.  With a properly configured Task constant, many DAQmx routines will need only a few functions -- Start Task, Read/Write, Stop Task, and Close.

Do some reading and thinking.  And find out what the real Error Message is, please ...

Bob Schor

[Omershah]

I have this error how can i explain this to you. But here is this error.

And yes i have posted two problems. Since my project is to create a test bench for myDAQ. So i have to prepare a loopback function for every input output of myDAQ to check them.

I attached the picture in which this error message is clearly stated. I am trying reading and thinking but i dont know why i dont get a proper solution.

But thanks for your kind help. But the problem in digital and audio are still not solved and i am trying. Please see the error message in the attached file.

Also the digital VI error screenshot is attached.

Regards

Omer

[Bob_Schor]

Read your Error Message.  The number is -200077 (very different from 200077).  The error tells you what is wrong -- fix it.  I told you to open your myDAQ in MAX and "explore" it -- you didn't do that, or you would know that the Audio I/O has voltage limits.  I suggested you create a Task in MAX or in LabVIEW Project (which would let you specify the voltage range for the Audio I/O channels) -- you didn't do that.

We are not here to do your homework for you.  We will suggest how you can find the answers to your questions, and you can choose to follow or ignore our suggestions.  However, if you do ignore us, then please don't come back and ask the same question again.

Bob Schor

[mikeporter]

Like I said in the very first response to your question, you have two possibilities. You can be asking the card to do something it can't do. Or you have two settings in conflict. 

Does the myRIO hardware have multiple input ranges? If so what one do you have selected? If not, you need different hardware.

Mike...

[Omershah]

I know the range is between +2 and -2 V.

I will try on your suggestion. I did my home work but this is a little problem and i was told that i can get help from the forum and i did get for which i am thankful and i will work on it.

Don't get angry dear. Thanks for the help. If the problem did not solved i will ask then.

Thanks

[Omershah]

@mikeporter i am  using it in the range of the devive which is between +2 and -2V.

I did this project using expressVIs but now the problem is i had to do it with DAQmx read and wrte module.

I am Attaching both the VIs if you can find the error please help.

Regards

Omer