function generation from Create AO Channel

[tbob]

WOW!   Dennis was not at all being nasty or condescending.  But you certainly are.  He is trying to help you and you bite him.  Shame, shame, shame. 

Here is another surprise.  Dennis does not work for NI.  He is a volunteer, like the rest of us.  No one here works for NI.  We graciously offer our help because we like helping others. 

Dennis did not call you a liar.  He pointed out that your situation causes an error when he runs it, and I believe him.  Maybe there is a reason why you don't see the error.  Probably a bug in your code.

If you want help, you will just have to learn how to be gracious.

 "the reason you're not seeing any errors is because your VI has automatic error handling turned off"...   I think you owe Dennis a huge apology.

[walter-donovan]

tbob. I would like to defend myself. Firstly, look at any of my requests for help. I am always gracious and thank those who offer help. I did exactly that in this case also. I have an issue with Dennis because he really seems to hate those he helps. In many, many cases. If you would like I will compile a list of condescending responses by him where he shows no patience at all with someone that doesn't understand something he has said. I thumbed back a few days and counted eight. As far as Dennis not calling me a liar, please reread what he said. He even made bold the word "do". I said no error. He said I did have an error. How is this construed in any language as not being called a liar? In your comment "He pointed out that your situation causes an error when he runs it" please think this out carefully. He did not have my source code as I did not post it. He simply argued about what I said I saw on my computer in my office. I understand when you say "Maybe there is a reason why you don't see the error." and "the reason you're not seeing any errors is because your VI has automatic error handling turned off"...  Mr Knudson on the other hand, did not think there could possibly be any reason whatsoever. He simply said that I do get an error. You know the funny thing about this whole thread is that the offending remark came after the thread was marked resolved...... As if someone who had nothing usefull to add could not miss an opportunity to argue. That is what my point is based on. Sorry if I offended anyone else.

[Dennis_Knutson]

You are generating an error but are not seeing because you did not bother to wire up an error indicator.

[walter-donovan]

Thank you. Actually it is not a case that I "did not bother". I am very new to Labview and do not know as much as you or others here. My experiences are that Labview has its own internal error generators and although they will stop or pause a program, they will also point out errors and not allow a program to operate past them. Apparently I am wrong but this in no way shows a situation where I "did not bother". You do understnad that it is exactly this type of condescending remark that I misinterpret as condescending, right?

[Dennis_Knutson]

Sorry if you feel that my original remark was condescending. I was simply pointing out the fact that an error is actually generated when you said there were no errors. There is automatic error handling if you enable it and if you don't override it by wiring up the error clusters. When you wire the clusters, you need to provide your own error handling.

[EMSS]

Hi,

     I am generating 1 Hz signal in ni 9263 at the rate of 1000Hz. I put this relation as thumb rule can any one suggest me how to set rate for AO card

for a required frequency. For example: If I want to generate 1.2 Hz at what rate I have generate for ni 9263.

Card Specfication:

NI 9263

4-Channel, 100 kS/s, 16-bit, ±10 V, Analog Output Module

• 4 simultaneously updated analog outputs, 100 kS/s
• 16-bit resolution
• Hot-swappable operation
• -40 to 70 °C operating range
• NIST-traceable calibratio

thanks in advance

Regards,

E.SundarRajan

+91-7569043526

[Paul-D]

Hi, this is Paul with Applications Engineering at NI.

In the future, we would prefer that you start a new thread for a question like this, given that the thread has been idle for a while.  This will give your question more visibility, identify it as a separate issue, and you will probably receive more support from the community.

As for your question, we have plenty of resources built into our software and on our website to help answer your questions.

For creating your signal, you could use something like our Simulated Signal Express VI or one of our other waveform generators.

For outputting your signal, you could use something as simple as our DAQ Assistant.

A good example included in LabVIEW is located at Help>Example Finder> Browse>Hardware Input and Output>DAQmx>Analog Generation>Voltage>Cont Gen Voltage Wfm-Int Clk.vi.

As for picking the frequency of the signal you want to generate, and choosing the sampling frequency of your output, you will need to choose these values based on what the demands of your application are.

Regards,

[EMSS]

Hi Paul,

           Thank your very much for the reply, but I Know the procedure to generate AO signal using Express as well as basic Function generator.

               NI 9263 support 100KS/s for one channel(Obviously 25KS/s for each channel if I am using all channels)

               The above mentioned rate supports me when I am generating 1k signal of any type in continously

               But when I try to generate signal of 1Hz at the same rate my signal coming in broken manner, so I kept rate as 1000 then it came.

               But I have to generate 1.2 Hz along with this I will generate 2 AO signal their frequency ranges from 1Hz to 2KHz(i.e I am generating 3 AO                  signals of different frequencies)now at what rate(rate for the clock) to generate  the signal. To provide these rate I need the relation between     these parameters

Thanks & Regards

E.SundarRajan

+91-7569043526

[Paul-D]

Sundar,

Just to clarify, although for this application it doesn't sound like you'll need it, your module actually supports simultaneous updating, which means each of your 4 channels can update at up to 100kS/s individually.

There is no hard set rule as to how many samples you should generate to create a signal, but it is possible to overflow your buffer.  In this case it sounds like you are producing 25,000 samples a second to produce a ~1Hz signal, which sounds like a bit overkill.  Because your sample rate is so slow, and you're giving your module so much data, it sounds like you are overflowing your buffer.  Try a smaller set of samples, and possibly a smaller buffer size.  At 1Hz samples as low as 100/s create a decent signal with minimum aliasing, 1000 samples/second should produce a very smooth signal.

Have you tried viewing the data you are trying to write on a graph indicator?  This is a good way to verify that you are sending the data that you think you are, and that it looks appropriate.

If you continue having trouble, please post the error that you are receiving.  Also, if you continually can't figure this out, then you can post your code to the forum and we can take a look at it.

Thanks,