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Member
Kadeel
Posts: 15
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Step input function

I am trying to create a step input on a graph. The input wave will start at -10ms and finish at 50ms. The height of the step input is 10V. Can anyone help?

 

Regards,

Kadeel

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Dennis_Knutson
Posts: 33,798
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Re: Step input function

What exactly do you need help with? Have you tried the Ramp Pattern on the Signal Processing>Signal Generation palette? Have you searched for Ramp/Step in this board?

 

If you are creating a pattern in software, the x axis of a graph is whatever you define it to be with  x min and  x max. You can set the offset and multiplier from thegraph's property page.

Member
JohnS11
Posts: 67
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Re: Step input function

Is there any example using the Ramp Pattern on the Signal Processing>Signal Generation palette  to create the step input?

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Dennis_Knutson
Posts: 33,798
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Re: Step input function

Did you try creating the code shown in the help for it? Or are you one of those that don't keep that window open?
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P@Anand
Posts: 2,325
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Re: Step input function

Yes there are examples and you can still find it by right clicking the function (In your case right click the Basic Function Generator) in LabVIEW. For creating step function why do you need a function generator you can directly step the value manually to the desired value.

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The best solution is the one you find it by yourself
Member
JohnS11
Posts: 67
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Re: Step input function

Yes, I read the help windows.

 

If i use the pulse pattern, if I key in the samples=22, amplitude=1, delay=2, width=20,  the waveform i see as described follow:

 

I see at it reach 1 at 2 second, and continuous(Still at 1) to the 21second.

 

Can we assume samples = time? meaning, the pulse pattern will stop at 21 second?

 

Does it means , after 21 second the signal already get chooped off (meaning dont have the off)...this is trying to get the step function.

 

 

 

 

For the Basic Function Generator, how to simulate a singnal at 2s at the amplitude of 1, and i continuous till 21 second(no off period)...to simulate the step function? 

can I have a look on the vi for that?

Member
JohnS11
Posts: 67
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Re: Step input function

what do you mean by  "directly step the value manually to the desired value"?

 

if i want at the 2s, it reach the amplitude 1

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P@Anand
Posts: 2,325
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Re: Step input function

Create a function generator vi in that give the desired value to which you want to step (for instance ao1 you are using and the present value it holds is 2 V and your desired value is 4 V as step). Check the time once 2 s is reached give the desired step value (So once time reached give the 4 V command to ao1 so it will hold the same value until you give the next one). It just works like a switch from one value to other.

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The best solution is the one you find it by yourself
Member
JohnS11
Posts: 67
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Re: Step input function

thanks for your explanation. can have a simple vi describe that so that i can modify from there?

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P@Anand
Posts: 2,325
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Re: Step input function

I have attached a vi for your reference you can use that as a sub vi ( You have to modify it as per your logic). The vi steps the signal after a defined period of time and holds that until the next trigger happens.

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The best solution is the one you find it by yourself