Triangle waveform

[EGMU]

Thank you very much for this file.
But I'm want to simulate continuous sine and triangle wave. And get continuous PWM. Please help me. Thank you.

[Paul_C.]

Hi,

The Simulate Signal Express Vi can generate sections of a waveform.  By placing it inside a while loop, you can continuously generate samples of the same waveform.  If this is what you are looking for, I would suggest taking a look at the following modifications that I have made to the VI.  In addition, to see the entire signal that has been generated it might be better to display the information on a chart that contains history.  I had added a chart to show you what I mean.  You might need to make some modifications to the loop rate, number of samples generated (for each iteration of the while loop), and size of the chart history to make these look how you would like them to look.

I hope this helps,
Paul C.

[EGMU]

thank you very much, Ima U  ,Paul C.

[10310]

I want to generate 6 pwm signals to port0/line0 - port0/line5 for drive my gate driver. But it error at picture "error daq.bmp". How can i generate 6 pwm signals for drive gate driver. i want 6 pwm signals output. Thank for your help.

ps.1 my daq device is pci-6221 and my labview is version 7.1 express
ps.2 daq assitance is port0/line0, daq ass2 is port0/line1, ... , daq ass6 is port0/line5
ps.3 English is not my primary language.

[Raajit_Lall]

Hi,

The error "-200524" that you are getting is because the boolean array that you are feeding into the DAQ Assistants does not match the number of channels that you have configured in the DAQ assistant.  For example, if you have a DAQ assistant which is configured only for 3 channels and you feed in an array of booleans which have elements more/less than three initialized, you will get that error.  To fix this error make sure that the number of elements that are initialized in the boolean array matches the number of lines that the DAQ assistant is configured for you.  In order to test this, you can right click on the wires just before the DAQ assistants and check exactly what are the values that are being input to the DAQ assistant.

Here is a knowledgebase article that will help you as well.  For future reference you can just enter error codes like the one you have into our support website search and you will be able to find knowledgebase articles like the one I linked to.

Hope all of this helps.  Please let us know if you have any further questions.

Regards,

[10310]

I'm read the pages that you tell me. Now my program is not error. But it isn't generate the signal that I want from daq output. How can I get that signal.

PS1. I think my output signal is digital output.
PS2. English is not my primary language.

Thanks a lot.

[Raajit_Lall]

Hi,

I am glad the error is not occuring anymroe.

Could you tell us what is the signal that you are seeing instead of the actual wave?  Are you able to see the correct wave on the front panel and its wrong on the DAQ output or is it wrong on both?  Paul posted a VI that outputs a PWM signal with a triangle wave.  Does that not work for you.  Could you give us an image of the actual signal that you want to see.

Thank you,

[10310]

On the front panel, I get the correct signal. I send that signal to Daq Output and measure that signal,but i didn't get that signal on Daq output. I get only sine wave on Daq output ,but I want PWM signal on Daq Output. how can I get that?

I send my signal on digital output on Daq output. I send it on port0/line0 and I measure it on terminal 17(P0.1) and terminal 50(D Gnd). But i didn't get My PWM siganal. I get sine wave. My measure is ok?

PS. My LabVIEW is version 7.1

PS2.English is not my language.

Thank you

[Raajit_Lall]

Could you please tell me how you are measuring your wave.  Since you are measuring on a digital port there should be no way that you are measuring a sine wave.  That is only a digital line.  It does seem that your LabVIEW code is fine, although as I pointed out in the last post, the array will determine the number of channels that you are writing to.  You could combine the DAQ Assistants into just one and write to a port using that.  Your method should still work though, but could you please check the terminals that you are checking on because you should not be seeing a sine wave.  Could you also tell us what kind of scope you are using to test the signal.

Thank you,

[10310]

Thank a lot for your help.

Last time I measure wrong way so I get sine wave. But now I generate the file that I post and this time I measure it that I tell you last time but I can't get digital output on DAQ output.I cheack the teminal already. It's ok. I cheack it by DAQ Assistants and click test,I get 0V when I choose 0 and 5V when I choose 1. How can I get my signal.I will post my file to you.Could you interface my file and the terminal.

Thank you.