How to get delayed pulse train

hello,
i am using Labview 7 and a PCI 6014 interface card. i want to generate delayed pulse train. for this purpose i am generating a analog waveform using 'function generator.vi'. i supply this waveform to a counter and to generate delay i am using 'finite pulse train(daq-stc).vi'. when i set trigger mode to 'no trigger', the VI works fine. But if i supply generated waveform to the counter gate(i.e. setting trigger mode to external), i see for sometime pulses missing are missing. I have also tried several other VI's(like 'delayed pulse easy.vi' and 'cont pulse train easy.vi'), but facing same problem. Can you please tell me how can i solve this problem.
regards,
Abhijeet

hello Alan,
Ok! here i explain my code. My requirement is to supply contineous 5V pulses at around 10Hz to a camera. After some time of the rising edge of pulse to the camera, i want to trigger Laser-1 and after some time of rising edge of the pulse to the Laser-1, i want to trigger Laser-2. In PCI 6014 there are only two counters which i am using for two Lasers(for delay generation). For Pulse train generation i am using 'function generator.vi'which is basically a waveform generator, but to get pulse train i set offset equal to amplitude. I supply this pulse train to two counters. To generate delay from the counters i am using 'Delayed pulse easy(9513).vi' which i have put into while loop. To see the output i am using 2-channel oscilloscope vi where i see some pulses missing. Also I obsereved pulses missing when i supply the output to the Lasers(Lasers stops firing for moment).
I am attaching a timing diagram which is explains my application and a labview code where i have combined three VIs (one 'function generator.vi' and two 'delayed pulse easy(9513).vi').
Thank you,
Abhijeet
Attachments:
camera+laser1+laser2.vi ‏188 KB

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number_of_steps.txt ‏17 KB
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Tiano,
I will try to better explain the paragraph on LabVIEW. The original paragraph reads ...
"While in a loop for continuous pulse train generation, make two calls to Counter Set Attribute.vi to set the values for "pulse spec 1" (constant 14) and "pulse spec 2" (constant 15). Following these calls you would make a call to Counter Control.vi with the control code set to "switch cycle" (constant 7). The attached LabVIEW programs demonstrate this flow."
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pec 1" and "pulse spec 2". These two registers are used to configure the frequency and duty cycle of your output frequency.
The example program which is attached to this Knowledge Base demonstrates how to change the frequency of a continuous generation on the fly. Why continuous? Because changing the frequency of a finite train would be easy. When the train completes it's finite generation you would just change the frequency and run a finite train again. You would not care about the time delay due to reconfiguration of the counter.
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How to continuously generate a pulse train with variable frequency

Dear all,
I am trying to use NI-USB 6259(BNC) to send Pulse signals to conduct position control of a servo motor with labview. The position control of servo motor follows these rules:
The number of the pulse train determines how many degrees the motor rotate ;( e.g. the angular position of motor)
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0-1
923
1
923hz
1-2
3540
0
3540hz
2-3
1751
1
1751hz
3-4
2663
0
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353
0
353hz
5-6
1017
1
1017hz
6-7
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1
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0
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I have already use the counter output of DAQmx, it just can generate pulse signal with certain numbers and certain frequency in one time. The attachment is the vi which can generate a finite digital pulse train from a counter output channel and the frequency, duty cycle, Initial delay, and Idle state are all configurable.
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Solved!
Go to Solution.
Attachments:
Counter - Finite Output.vi ‏57 KB
Finite output.png ‏13 KB

Hi aacuna,
Thank you for your reply!
I already checked that article. The frequency in that Vi can change dynamically, but the method of adjusting the frequency is ‘manual’ .Below is the front panel of that Vi. When the Vi is running we can change the frequency by press the button.
Time(s)
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0-1
923hz
1-2
3540hz
2-3
1751hz
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Thank you！

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Sequence 3 tasks - create a finite pulse train-create a delay by creating a pulse train-measure pulses

Hello
i use a board 6023E and pc pentium4 3Ghz
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Second create a delay for this i use again a conter to creat a pulse train in witch the delay is equal to frequency x number of pulses.
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In attachment i send a picture with my program.
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picture with my program
ftp.ua.pt/incoming/labview/sheme
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How do I output a finite pulse train through multiple counters?

Hello,
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Here's a screenshot of the code I put together on how to use multiple counters. Also, take a look here for more information on how to sync multiple counters.
Message Edited by Knights Who Say NI on 02-02-2009 10:36 AM
Message Edited by Knights Who Say NI on 02-02-2009 10:36 AM
Message Edited by Knights Who Say NI on 02-02-2009 10:38 AM
-John Sullivan
Analog Engineer
Attachments:
4xcount.jpg ‏67 KB

How to change the frequency of a finite pulse train?

Hi all? I Know I’ve asked once a similar question, but I need a better answer. I would like some ideas or examples on how to modify the example in LV; "Finite Pulse Train Generation - Intermediate for AM9513-Based Devices",so that the frequency can be changed while the VI is executing.
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Tiano,
I will try to better explain the paragraph on LabVIEW. The original paragraph reads ...
"While in a loop for continuous pulse train generation, make two calls to Counter Set Attribute.vi to set the values for "pulse spec 1" (constant 14) and "pulse spec 2" (constant 15). Following these calls you would make a call to Counter Control.vi with the control code set to "switch cycle" (constant 7). The attached LabVIEW programs demonstrate this flow."
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The example program which is attached to this Knowledge Base demonstrates how to change the frequency of a continuous generation on the fly. Why continuous? Because changing the frequency of a finite train would be easy. When the train completes it's finite generation you would just change the frequency and run a finite train again. You would not care about the time delay due to reconfiguration of the counter.
If you would like to change the frequency of the pulse train using a knob, this functionality will have to be added in the while loop. The while loop will be continuously checking for the new value of the knob and using the knob value to set the pulse specs.
LabVIEW is a language, and as with learning all new languages (spoken or programatic) there is a lot of learning to be accomplished. The great thing is that LabVIEW is much easier than mo
st languages and the learning curve should be much smaller. Don't fret, you'll be an expert before you know it. Especially since you're tackling a challenging first project.
Regards,
Justin Britten

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