Acquire 2 digital signal with custom scaling (Engg Units)

I am a newbie to DIO world.
I have write a VI to acquire 2 digital signals. one from a load cell and other for motor rpm (pulses). I need to acquire these two signals and then convert them into engg units using custom scaling and write them to a txt file with time stamp.
Please suggest best ways to accomplish this task.
Thanks
DAQG
Solved!
Go to Solution.

Look at the examples on DAQmx in the example finder.
You wouldn't actually be acquiring 2 digital signals. You would be acquiring an analog signal from the load cell. A digital or counter acquisition is what you would acquire from the motor. Search for analog measurements and counter measurements in the example finder. Some of the example should show you how to apply the custom scaling.

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Acquire a signal with mac osX

Hello.
I am a very beginner with LabView.
I would like to acquire a signal with a NI-USB 6009. I have LabView 10 on osX 10.8. I already installed the daqmx base driver.
Could you explain me how to acquire a signal which come from the NI USB 6009 and export it as a list of numbers (the amplitude and the time).
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Hello matttgic,
What kind of signal do you want to acquire/generate?
For exemple, if you want to acquire an analog input, you should use the architecture use in the file "Analog_input attach to this email.
As Johnsold told you, you can find some code for your device in the "find exemple" section of LabVIEW.
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Attachments:
Analog_input.PNG ‏13 KB

Acquire generated signal with this hardware ?

Hello everyone,
I didn't really know where to post this, I apologize if it's the wrong place.
I'm very new to the LabView thing, and I have for project to trigger an injector and so to create a digital signal like this:
Due to the characteristics of the signal (110V, 10-20A, injection duration: ~20ms), someone recommended me this hardware (sorry if I'm not allowed to post these links):
- programmable power supply: http://fr.farnell.com/ea-elektro-automatik/ea-ps-9200-25-2u/alimentation-1-voie-200v-25a-prog/dp/2422474
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I have designed and built injector drivers. To get a waveform somewhat like the one you showed requires a sophisticated and fast control circuit. I would not call that a digital signal. It may be controlled by some kind of logic signals, but that is an analog signal. No programmable power supply I have seen is fast enough to come close.
The pull-in current does not typically go into a ring/overshoot flat-topped waveform as you have shown. It follows an exponential curve defined by the L/R rise time and the current limit set by the supply voltage and the injector coil resistance. For the injectors I have seen that current limit is much higher than the current required to generate the magnetic field required to open the valve. That oscillatory response could be the result of a switch-mode current regulator.
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Generate complementary 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.
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(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.
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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.
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.
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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 .
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Sequence 1create output digtal signal- 2 make microseconds delay or less- 3 measure digital signal with board 6023e

hello
I need creat a digital signal and for this i use a counter output and then i need creat a delay after a signal measurment and for this i use again a couter. My problem is how i can make this delay betwen create and measure a signal. this delay must to bethe shortest possible and precise. une of my attemps was make a sequence and for make the delay i create a task for une virtual output with max frequency 5000000hz and just une pulse but i dont know how many time the labview get to go by the first task ( creat a output pulse and ent it) to make tis task before discribed to the last task (measure a digital sinal). Another thing that i dont know is how many time the libview get to create and eliminate une task. Une information beyond the kind of board (6023E) that can be useful to help me with this problem is the information about my pc in this case i use a pentium4 3Ghz.
thanks

...My problem is how i can make this delay betwen create and measure a signal.
...how many time the labview get to end one task and start another one.
What I tried to say is, that even if you use the counter of the 6023e-Board
to create the delay and trigger the measure via LabView under Windows,
you leave the realtime-path. Executiontime of LabView-code is then not
determinated.
One way to solve this, is triggering measurement via hardware and use LabView to read Data from the Buffer of the DAQ-card.
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Lorand

Capture digital signal with DAQ 6015

I am wondering what is the best way I can capture a digital event accurately using my DAQ 6015 Pad. It seems as though I can only capture it using (on demand) timing which I'm assuming means it will only capture it as fast as the loop iteration. I'm looking to monitor this signal with accuracy down to about 10 ms. Are there any good digital examples i can goto that you can vary how fast you can capture an event using the 6015?

Hi caunchman,
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Acquire 2 signals with different sampling rate?

Hello,
i am using first time labview signal express together with a NI pci 6251 & NI Scc 68 device.
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hello markus_umd,
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HELLO,
Do you have an example of this program ??
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Thank you for your help!

Hi,
You can find examples in the LabVIEW "NI Example Finder". You can access it in the LabVIEW help menu. Click on "Toolkits & Modules" then "Real-Time" to find RT examples.
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Hello Sound Tech
You do not have to put another step inorder to acquire multiple channel. In the first DAQmx Acquire step you can select multiple lines by pressing Ctrl and configure your timing and you will be all set.
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nAyer

Parallel acquire 2 signals with different sampling rate on 2 cards

Hi NI,
I have cDAQ-9178 and NI 9221, where sample rate is 10kHz and NI 9219, where I need sample rate about 10Hz, it's possible this confiruration for parallel acquire?
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Neolker

Hi Neolker,
Do the tasks need to be synchronized or are totally independent tasks?
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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).
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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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Chris

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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.
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I don't know how to check the rising edge of 6 different channels occure at the same time.
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Thanks

Hello,
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When I try to open a previous Setup file it no comes up with an error stating it cant find the calibration values!
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Ok sorted.
Refitted old disc with previous system on it. Ran Measurement and Explorer and then exported the configuration data.
Fitted new disk, imported configuratio data and all the scaling is restored.
Useful lesson, I had always thought the scaling was held in the TDMS files but its in the .nce files from the measurment and Explorer.
mike

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Hi
I have a quite uncommon problem. I need to acquire the encoder signal with a NI-9201 (analogue module).
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Hi Yves,
when you acquire data from an encoder, do you mean a quadrature encoder or rotary encoder?
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How did you acquired the slower signal until now?
Kind Regards,
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Hi,
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Acquire 2 digital signal with custom scaling (Engg Units)

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