Scripted Waveform Generation Problem after 100ms

[giorgos_str]

Hi all

I am a beginner user of labview and currently i am facing a problem.

My professor, who i'm working for has given me a program in labview

creating scripted waveforms, which basically they are producing pulses.

Now when i try to create two pulses of 50ms each with an interval of 30ms

in between them i get a constant "on" signal. Now when the sum of my both pulses

duration and the time interval between them is less than 100ms the whole thing works fine.

Any help would be appreciable.

Thanks in advance.

Giorgos 

[GovBob]

Goirgos,

 In order to receive some help on your problem it would be helpful if you could provide the following:

What version of LabVIEW are you using?

What hardware are you using to generate these pulses?

Post the code you are using with the Add attachements button if possible. If you aren't allowed to post code at least post a picture .png of the block diagram.

Open the example finder in LabVIEW and search for "pulse".

None of us have a crystal ball

Message Edited by GovBob on 04-28-2010 04:49 PM

[giorgos_str]

I am currently using Labview 8.5  and the hardware creating the pulses is PCI 6541.

[GovBob]

Giorgos,

 First I don't have your hardware or mathscript (NI made it an add on toolkit for 2009 ) so I'm not sure how much help I can be as the the vi is broken for me. What I did notice when I opened your vi is that the entire generation chain is disabled.

 Are you just using the front panel digital waveform graph to see your problem? One thing you could try is to increase the "End Time (ms) 2" control on the front panel to see if that helps. Also make sure the x-scale of the graph increases accordingly.

[Dimitrios]

Hi Giorgos,

I don't have your Hardware but it seems i can run your VI because you have that part disabled on your block diagram.

But i am struggling to understand how to run you VI (even after i read your documentation).

Could you please set your controls, led's and timings on your Front panel and send me an image of it to try to replicate what you do?

 I am not sure if i will be able to help but i will give it a go.

Regards

Dimitrios

Test Systems Computing Engineer

Cummins Turbo-Technologies 

[giorgos_str]

Thanks guys for your responds

I have already tried to change the end time but there is no effect and the x-axis is automatically adjusted with the new end time.

The problem is that in the front panel i get the right waveform i am supposed to get.

However when i plug in the oscilloscope the signal i get is just a constant "on" pulse. 

Giorgos 

[Dimitrios]

Hi Giorgos

Not much i can do without your hardware. As you said when i am trying the timing of 50ms with 30ms inbetween it works fine on LabView.

Sorry mate...

Dimitrios

[jschwartz]

Hi Giorgos,

What is your application?  LabVIEW has a lot of built in examples that you can find in the Example Finder. You can get to the Example Finder at Help >> Find Examples.  When the Example Finder opens, double click Hardware Input and Output >> Modular Instruments >>NI-HSDIO.