Generating digital signals (T/F) continuosly at certain frequency

Please help me in generating digital signals continuously (TRUE/FALSE alternatingly) in LABVIEW 7.1. I want them to be crreated at frequency which can be controlled by myself. Kindly help its urgent. Contact me at [email protected] Thanks Rahul

Have you looked at the shipping examples for DAQmx? What kind of DAQ card do you have?
p.s. since all questions are answered here, posting your email does no good except put you on a list of spammers.

Similar Messages

  • Generate digital signal for 6722 or 6221

     Hi,
    first thanks for the help I already got on this board.
    Now I've got the following problem:
    I like to generate a digital signal: high for 300µs, low 300 µs, high 300µs, low 300µs, high for about 2ms.
    I am looking for a solution how to generate this digital sequence. At the same time I will read the information back via an analog input (hopefully I have now a solution for this problem).
    I tried to find examples but I wasn't successful. At the moment I was not able to produce any digital sequence which worked.
    My hardware is either 6722 or 6221 - which should be OK regarding the timing.
    Thanks
    Solved!
    Go to Solution.

    Find attached example.
    I am not allergic to Kudos, in fact I love Kudos.
     Make your LabVIEW experience more CONVENIENT.
    Attachments:
    Digital Waveform [LV 2009].vi ‏14 KB

  • Is there a better way to generate custom timed digital Signals

    I am trying to generate digital output of high and lows with particular delays on different lines. Each daq assistant is activating single line on a port on USB 6501. There more complex high and lows that I need to generate with variable time difference between high and low. There is codebelow which accomplishes what I am trying to achieve but for executing a long pattern of high and low signal is very time consuming to do this way. I am sure there is a better way to do this, I  not a expert on labview so I haven't uncovered its full potential. Can anybody suggest a more effective and a quick way to do this. I would hgihly appreciate. Thanks!
    I have not shown in the code below but through DAQ assistant I have initialized lines to low level logic.
    Solved!
    Go to Solution.

    See the attached file
    Attachments:
    Digital Signal.vi ‏335 KB

  • Generate complement​ary digital signals with dead time between each pulse and controlled by duty ratio

    I am to generate  two complementary digital signals using NI 9606 conected by RIO Mezannine Card to NI 9683 (Half Bridge DO).
    I am able to generate the signals but I am not able to put dead time between high and low signal and also, low and high signal.
    Requirement:
    (1) When the first signal goes high and the second signal goes low, there should be a controllable dead time.
    (2) Also when the second signal goes high and the first signal goes low, there should be a controllable dead time.
    I am able to do requirement 1, but I am unable to fulfill requirement 2.
    Please have a look at my VI and let me know how to go about satisfying requirement 2.
    Attachments:
    complementary test 2.vi ‏69 KB

    Hi Frank ,
    I have already taken note of the example Tannerite has provided  and have built my vi ( attached in previous post) surrounding that example.
    Now I require to control the PWM duty cycle as you can see from the vi using a knob and that control refers to both the signal 1 and 2.
    Now the signal 1 end and signal 2 generation requires a controllable dead time. Similarly, signal 2 end and signal 1 geneeration also requires another controllable dead time.
    I am able to do either one dead time at a time using delay but not two dead time simultaneously.
    I feel that I have two put the delays at the appropriate data flow point. I am working on that.
    I would really appreciate if you could give some insight on how to solve this dead time issue and generate two complementary waveform with dead times whose duty cycle can be controlled by a knob controller in fronty panel .
    I have also posted the required timing diagram for reference as suggested by Tannerite.
    Best regards.

  • Generating a digital signal

    Hello,
    I am trying to  generate a digital signal which can be controlled in terms time i.e. Switching ON for 10 minis off for 5 minutes. I tried to generate a digital signal which is going high but unable to control it. As I am the beginner in labview any kind of help is appreciated.
    Please see the attachment for the developed block diagram
    Attachments:
    digital signal generation.vi ‏17 KB

    It appears that all you posted is one of the shipping examples. Is that all you've tried? You can't control it because you're not actually doing anything inside the loop. You're simply setting the value high before the loop starts, and not changing it in the loop. What kind of device do you have? Is it software controlled? If so, you will need to keep track of the time inside the loop. You can use the Elapsed Time VI to do this. Attached is a simple example to get you started to see how this can be done. I'm sure you can figure out how to integrate what you did and what I've shown you.
    To learn more about LabVIEW it is recommended that you go through the introduction material, tutorial(s), and other material in the NI Developer Zone's Learning Center which provides links to other materials and other tutorials. You can also take the online courses for free.
    Attachments:
    Switching signal.vi ‏29 KB

  • MyDAQ - Generating a digital signal and displaying it on an analog waveform graph

    Hi,
    I am using the NI MyDAQ to generate a digital waveform with an adjustable frequnecy. This is being implemented into a program I have already written which generates a TTL "like" pulse out of the sound card. I am displaying the output on an analog waveform graph, and I'd like to be able to display the digital waveform generated by the myDAQ on the same graph. (Not at the same time, either one or the other, toggled by a button). I've been messing with arrays and conversions but I cant seem to really get anywhere with it all.
    This is the vi I have made to generate the adjustable frequency digital signal with MyDAQ. Any suggestions on the proper way to do this if the following is wrong would be great too as I just got the MyDAQ a few days ago. I would think there must be a better way but this is the best I could come up with so far.
    Solved!
    Go to Solution.

    Hi Jonny,
    The general logic you are using to create a digital pulse train is fine. This VI you've written should work and will create the pulse train based on software timing (which is fine because you don't have hardware-timed DIO on the myDAQ anyway). However, it is usually good practice to start the DAQmx task just before your while loop and then clear the task after the while loop when you press stop.
    For reference, there are some pretty good LV examples that I recommend looking at for this application too. If you are just trying to create a digital pulse train, the example Gen Dig Pulse Train-Continuous.vi is a good example that uses a counter to create a digital pulse train of your desired frequency. This is generally the prefered method to create a pulse train if you have the hardware available to do so (the myDAQ does have a counter). Alternatively, there are some DIO examples that continuously write to a digital line/port.
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    myDAQ Counters 
    myDAQ Manual 
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    Chris G
    Applications Engineer
    National Instruments

  • How to check 6 digital signals change value at the same time with PCI-6229??

    I am using DAQ card PCI-6229.
    Channel 1 generate a digital signal.
    Channel 2,3,4,5,6,7 acquire digital signals.
    I want to check:
    1. Whether the rising edge of Channel 2,3,4,5,6,7 occures at the same time;
    2. The time delay from the rising edge of Channel 1 to the rising edge of Channel 2,3,4,5,6,7 is within a certain range.
    I know I can use counter to get the two edge seperation time delay. But I only have two counter, it is two time-consuming if I check one by one.
    I don't know how to check the rising edge of 6 different channels occure at the same time.
    Does anyone has any suggestions?
    Thanks

    Hello,
    You can use the DAQ card's digital input change detection circuitry to detect changes in the input, you can then use a counter to measure the relative time between samples. Please read Page 6-9 DI Change Detection Applications for more information. Let me know if this helps
    Christian A
    National Instruments
    Applications Engineer

  • How to generate a signal like this on PCI-6202 DAQ card

    I want to generate a signal like the one in the attached picture.
    Which have inputs like
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    2.Duty cycle
    3. No of pulses
    I have created a file which gives the signal like the other one in the end which has frequency of 200us and duty cycle of 0.5% that is 1us On and 199us signal off. Now i need to include some sort of condition that when the button is pressed then the signal of the require frequency, duty cycle and no of pulses is created as input by the user on the front panel, like the one which are first part of the signals in the picture below. 
    Attachments:
    singal_co2_laser.png ‏12 KB
    gen_digital_freq_duty_noofpuleses.vi ‏21 KB

    I can direct you to this forum post as an example and see if it helps you out. It seems very similar
    http://forums.ni.com/t5/Multifunction-DAQ/how-to-g​enerate-digital-signal-from-PCI-6221-like-the-one-​...
    Rob W.

  • Can we design analog to digital signal conversion block diagram (ADC) in labview

    hi every one,i've doubt i.e can we convert function generator output (i.e analog signals) to digital signal in labview......can anyone help me how to create ADC circuit that means ADC Block Diagram in LABVIEW.....please give me solutions for my problem

    Hi guru,
    from signal generation VIs you get arrays containing float values (aka DBL). Those floats are just digital values made of 0s and 1s…
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    GerdW
    CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
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  • DIGITAL SIGNAL GENERATION

    Hi!
    I want to generate a digital signal (0-5V) in order to turn on and off an hydraulic pump. The time on (high) and time off (low) are specified by a MatLab code, so that once the pulse has finished one cycle, the program should be go again to MatLab code and take two times again. Then it should generate the signal again.
    Thank you for the help.
    Miguel

    Thanks for the reply.
    I have a system with an hydraulic pump, power supply, transistor and computer. I would like to send a digital pulse from my computer (0-5V) to the transistor. The transistor then closes a circuit (power supply and pump), and the pump starts running.
    Then, I would like that each sample (each pulse) has specific width (time on), and also specific time off before it starts with other sample. These times (time on and time off) are computed by a MatLab code.
    I'm working with DAQmx drivers and I also have a BNC 2110.
    I also attach my code in Labview that I am trying to modify.
    Thanks a lot.
    Regards,
    Miguel
    Attachments:
    Gen Dig Pulse Train-Finite_original.vi ‏22 KB

  • Search data in a 2d array and generate a signal when found

    Hi, i am looking for an interactive way to search data from an array containing a 2d array found in a cluster. The data is in the 2d array. I have attached the vi containing the array. I want an interactive method to look up for the codes in the 2d array(found in the 1st row) and when found generate a signal to tell it has been found. The signal varies depending in which category was data code found (whether engineering, law or others). Btw the data i am looking for are in fact input using a barcode reader. Should i use a search 1d array function? or is there another method?
    Solved!
    Go to Solution.
    Attachments:
    Untitled 1.vi ‏6 KB

    Just to make sure we are totally clear here.  We are trying to find the cluster which contains a certain data point in its first row of the 2D array?
    There are only two ways to tell somebody thanks: Kudos and Marked Solutions
    Unofficial Forum Rules and Guidelines
    Attachments:
    Search for element.png ‏14 KB

  • How to output a digital signal on negative slope of the clock?

    Hi
    I need to output a finite length of the digital pulse which will start on demand at the negative slope of the imported (or exported) clock.
    I am trying to get the clock exported or imported, but in no case I can trigger outputting the signal on the negative slope. 
    What is the trick?
    thanks
    Pawel
    Solved!
    Go to Solution.

    Which device are you using to generate your digital signal.  What is the clock source?  Can you attach your vi?  Normally, there is a DAQ function to configure the trigger where you choose the trigger source and the trigger slope (rising or falling), which would be falling for a negative slope.
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    Inventor of the WORM Global

  • How can I generate digital output?

    I was introduced to LabVIEW and NI Elvis last month and I have been asked to generate three digital signals to control three different relays.
    what are the basic steps I have to do to generate the signals

    You may want to start with this overview.
    Your specific application is rather easy, so you may be able to even use the parallel port to control the relays, but that depends on the type of relay, current source/sink requirements, voltage requirements, etc.

  • Measuring digital signals coming from the HSDIO (PXI-6542) with the DMM (PXI-4070)

    Hello,
    in attachment you can find the program I'm using for my measurement: I'm generating and acquiring digital signals with the PXI-6542 and at some trigger point of one of those digital signals I'd like to capture the measured values on a plot with the Digital MultiMeter (PXI-4070).
    It does work if you configure the generation repeat mode as continuous, but if you do have a finite repetition (repeat count is 1) it doesn't react on the trigger, as if it can't find a trigger. On the other hand, if you have a finite repeat count of 30 or more it does react and triggers correctly again.
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    Is there a way to measure correctly when the repeat count is only 1?
    Thanks in advance,
    Jürgen

    Hey Jürgen.  I apologize that you haven't gotten an answer yet to your post.  I looked at your code and had some questions.  What is the source of your trigger to your DMM?  I see that you're exporting the data active event to PFI1, and your comments indicate that PFI1 and PFI2 are connected to give you a start trigger for your digital acquisition.  Exporting the data active event with a finite or continuous pulse should only give you a single edge per run, though - you wouldn't get a pulse each time.  Is your trigger coming from a data line?  I didn't see any line in your included data that would indicate a single pulse.
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  • Anybody knows how to control parallel port to generate digital line ?

    All,
         I have found at some website, there are a software can generate corresponding signal (I suppose that is digital line) to driver a relay board, the relay board is 8 channels. which out put is pin 2, pin3, pin 4, pin5, pin 6, pin7, pin8 and pin 9 of parallel port to control it . it is well control, how can it do ?  and I want to simulate it at LV with parallel port too , how can it achieve ? which command, or a simple sample which you provide will be appreciated.
    thanks in advance.

    You forget to search through NI Web site. Here are some links.
    http://zone.ni.com/devzone/conceptd.nsf/webmain/72C6FC6CE4AD4D1386256B1800794596
    http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B123AE0CB9CB111EE034080020E74861
    Sergey

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