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

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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.
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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.
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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.
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Find attached example.
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Attachments:
Digital Waveform [LV 2009].vi ‏14 KB

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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.
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Thanks for the reply.
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How to output a digital signal on negative slope of the clock?

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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.
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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.
- tbob
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Attachments:
Digital Signal.JPG ‏7 KB
Digital.vi ‏40 KB

cDAQ chassis do not currently support hardware timed tasks for digital modules with >8 lines. The DAQmx help defines these devices as "static digital I/O modules". The "Digital I/O Consideration for C Series Devices" section in the DAQmx help describes the capabilities of digital modules on different chassis.
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Solved!
Go to Solution.

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

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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.
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Attachments:
digital outputs delayed.png ‏8 KB

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Generating a digital signal

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