sampling frequency of DAQ assistant for pulse width measurment

Similar Questions

• signal level for pulse width measurement

  Hello

  I am able the pulse width with the meter M6251 (CI pulse width)

  

  I understand that the digital input works on the TTL levels (0, low 8V 2, 4V high).

  Can you say exactly in which the level of signal pulse width is measured?

  Thank you

  Ralf

  In fact, the transition from low to high (or vice versa) is located in between 0.8V and 2.2V.  It is not specced exactly where it will be (although you'd be able to get a better idea, if you have an analog source, you can slowly increase until you see line status change).

  This is why the fast rise time are important to accurately measure the digital signals.

  Best regards

• with pulse width measurement external sample clock

  Hi all

  I use a NI 6220 (programming with ANSI C) Board and I would like to make a "unique pulse width measurement' by using a signal from the outer door and an external signal source.

  The program and the card with the help of the "DAQmxCreateCIPulseWidthChan" command works only partially as expected. Namely, the outer door has worked, but the map uses the internal time of 80 MHz base signal instead of the external source connected to the source by default PIN (PFI, 8).

  I tried send an another PIN PFI on the default source pin using the command 'DAQmxConnectTerms', but this did not help either.

  Obviously, I'm missing something...

  Best, Uli

  Hi Uli,

  I posted in your thread here.

  Best regards

• How can I use two counters simultaneously to pulse width measurment

  Hello, everyone!

  I'm new to Labview. I currently have some cDAQ9171 and width measurment with 9401 impulses. My understanding is that the 9401 was 4 meters, which means that I can use these meter separately. However I have the following problem.

  1. I use ctr 0 and ctr 1 (PFI 1 and PFI5) to measure two different impulses. However, it seems that there is an interference between two counters. How can I make two counters working simultaneously and separately?

  2. I first try a pulse width measurment counter in Labview signalExpress. My pulse width is about 0.4ms. However, I can't get the right result, if I choose the starting edge is on the rise (the results always around 20ns. Only if I revise my pulse and pick the starting edge is down, I can get reliable results.

  I'm confused about these issues for about 3 weeks... Is there someone can help what can I do with that?

  I have attached a simple vi...

  Thank you very much!

  
  

• Simulate signals wired to the DAQ assistant for USB-6009 device

  Hello

  I'm trying to send a signal to the DAQ Assistant Express VI.  I watched the movie "Generating a Signal" on the Web site of NOR (www.ni.com/academic/students/learnlabview/generate.htm) and I have my Signal simulate connected directly on the DAQ Assistant, as shown in this film.  In my case, the DAQ Assistant sends the signal to a device USB-6009.

  However, I received this message:

  Error-200077 occurred to the DAQ Assistant
  Possible reasons:

  Requested value is not supported for this property value. The value of the property may be invalid because it is in conflict with another property.

  Property: SampTimingType
  asked the value: Sample clock
  You select: On-demand

  If I select 'On Demand' in my DAQ assistant and run the vi everything works beautifully.  However, I need my DAQ assistant to be configured to generate a waveform AC continuous, not output a single alternating current rippling.

  What happens here?  I did not have this problem before on other devices of NOR. I am using LABView 2010.

  Please answer.

  Thank you.

  double post

• NI6602 pulse width measurement: do I have to use an external sample clock?

  Hello

  In the example .NET 4 "MeasPulseWidthBuf_SmplClk_Cont", it is said in the comments that:

  An external sample clock should be used.

  Hi mola.

  This specific example measures of sample-clocked pulse width.  This type of measure is supported only on new hardware such as the X series cards and will not run on the 6602.

  Your application that you have linked uses Implicit timing, which means that the signal is using the sample clock.  In other words, at the end of each pulse duration which can be measured, the sample is deterministic locked in.  So you end up with a table in the buffer of each pulse width which is seen by the meter.

  Best regards

• single pulse width measurement

  Hello

  I'm trying to measure the duration of a single pulse using ctr0 on an SMU-6361.

  The signal in the attachment Capture7.jpg, goes PFI 9, ctr0 door.

  The problem is that the counter see ' s the front up and stops. The pulse width is not given as can be seen in the output (Capture8.jpg).

  I get the same results by using Meas_Pulse_Width.vi example.

  Is something wrong with my SMU-6361?

  Oh, I think I know what it is.

  Change the task "pulse width" (a single pulse of height) instead of "Pulse" (the high and low time of a pulse repetition measures).  Change the DAQmx Read to use Ctr > single sample > DBL (instead of pulse).  Change the property filter node digital to use the corresponding properties of the "pulse width" (the filter is still necessary):

  

  The task of the pulse was not period initially because you receive a series of noise pulse repetition (and so it was a very low period).  With the filter, this time since the noise disappears now and the single pulse did not finish measuring the pulse (which requires a high and some time):

  

  For the record, I agree that it is confusing that there is the "pulse" and "Pulse" measure and they do different things.

  Best regards

• NI 9401 pulse width measurement.

  Hello

  I'm not sure that I understand very well the pinout diagram. At the present time, I have a NI9401 in a NI 9172 chassis.

  DIO0 and DIO1 are connected at the gates of light. I have an opto switch and I want to measure the pulse width when an object blocks passes through the slot. Can I use one of the other free entry of the for do?

  The entries are DIO2, DIO4 and DIO5.

  The other IO pins are used as triggers.

  See you soon

  K

  Hi Kamilan,

  If you explore in the measurement and Automation (MAX) and find your 9401, you can right click on the device and select "Pin of the device" which pulls up a window that says what features each pin on the device.  For example, according to this document, DIO2 is PFI2 to THE CTR0 CTR0 B and FREQ OUT.

  To answer your second question, do a right click on your device and create a new task for your 9401.  "You should do an acquisition of signals" counter input "pulse width and select CTR 1 on your device.  Once you do this, you can configure the parameters of your task and Max it will tell you where you need connect your signal source, which, for me, is DIO5.

  I would like to know how it works for you, thank you!

• Full range of pulse width measurement

  Hello

  I'm having a problem with the measurement of PW, I need to read an operating cycle within a range of 0% to 100%.  The problem I have is the signal does not cross the Middle time enough baseline to measure or the histogram cannot be used because the amplitude is zero.  Yes, this is obvious, because there is no pulse, that's basically all true or all false these two extremes, but the pulse measurement vi cannot handle this.  Is there another way, I could measure the market factor, so that I can see if there is a hollow (0%) or high (100%) and everything in-between without errors?  Even when I measure the PulseWidth in the method of the Ridge, rather than the histogram method, which gives me more time to remain at 0 or 100% before it gives an error, the measure see the signal as duty cycle 50% (still a times obvious because it is neither salvation nor low for any length).  So if I could still read 0% or 100% error free, how would I be able to block the two extremes of the never read?  My entry is the acquisition of data, so I can't just 'limit' my input to the source signal...

  Any suggestions?

  Thank you

  -Corbin

  Hey, Henrik, thanks for the reply,

  I didn't really know how to integrage over a period of time in LabView, and I read a wave of digital squares (duty cycle).  I found that I needed to omit extreme values such as 0% and 100%, so I couldn't find a way to do this with one under VI.  What I found is my solution: I knew that + 12V has to be 100%, and 0 v is expected to be low, so I just used 'Amplitude and level measurements' sub VI read the RMS value, used a table that I recorded correspondence (via MatLab help), and I have more problems with errors due to levels of reference of histogram (do not use histogram now...).  My application can read everything from 0% to 100% and he returned my correct data after handling.  Success!

  He could go about resolving the issue differently, but it works.

  -Corbin

• Units of the number of samples and rates for the DAQ Assistant units

  Hello

  I use the DAQ assistant for analog voltage of an input OR data acquisition card. What is the difference between the rate and the number of samples in the DAQ assistant and what are the units of the two?

  Thank you.

  The number of samples is how many discrete to measures. Rate (per second) is how fast to acquire the specified number of samples.

  If number of samples is 100 and the rate is 1000 samples per second, then the acquisition would take 0.1 second (100 / 1000).

  -AK2DM

• Outbreak of DAQmx N-sample and the Acquisition using DAQ Assistant

  Hello!

  I'm still fairly new to LabVIEW and I am working on all the points of connection. I would like to acquire a finite number of samples of analog data from a CompactDAQ system when a Boolean event of internal software (like a button of VI). I followed the examples to implement the acquisition with the DAQ Assistant, which works very well. I don't understand how I can use a software trigger, but I don't see how hardware triggers are configured in the trigger tab in the DAQ Assistant.

  I don't know that this should be very simple; Maybe I'm just ignorant of the configuration used for this sort of thing. Also, I could find soon I need to go beyond the DAQ Assistant for some of what I want to do, so any pointers to good references or tutorials on programming DAQmx are welcome.

  Thank you!

  Ryan

  You can simply put the acquisition within a value of the Boolean control change event.

• DAQ Assistant as input for the formula

  I need the output to my DAQ assistant for that entry into a knot of formula. But I can't do it because the terminals are different; data Dynamics vs double [64-bit real (precision ~ 15 digits)]. Is there a way in which I can use these dynamic data in a node form?

  Look in the express palette under the manipulation of signal for an another express VI, called "DDT".

• Second DAQ assistant in the power control system does not

  Hi all

  I need your help on this issue. I'm currently programming a VI for one command power supply for pool boiling experiments. The organizational structure of the VI program is attached.

  I use two assistants DAQ for steady-state acquisition and temperature unstable state data respectively. The first assistant DAQ (samples to read 5, 5 Hz rate) for the acquisition of works unstable state data well (see the attached image file first DAQ Assistant for acquisition of temperature unstable state). The second assistant DAQ (samples to read 12 k, 200 rate) for stationary data acquisition does not work (please see attachment image Second Assistant DAQ of steady-state temperature acquisition), showing only a series of data files size of 1 KB with no data on the inside. And indicators for steady-state data also revealed nothing.

  After a similar Q & A search in the forum, I tried to distribute different channels for 1 and DAQ assistant 2. However, the situation was almost the same.

  The material I used are chassis SCXI 1000 and SCXI 1303 Council to acquire thermal couple temperature data. Food was AMREL SPS200-50-K025. LabVIEW software is the 2014 version.

  I had just started to learn LabVIEW for only a month, and I know that the VI is a little messy. Hope you guys can also give me some advice on how to improve this VI.

  Have you looked at the error on the second daq assistant? You will see that a reserved resource error because you cannot use two different assistants. You do not mention the real DAQ hardware but there a clock unique convert. You can use only one assistant with a unique sampling frequency.

• How to stop express vi DAQ assistant

  I am eager to collect data of a few strings at a time at a high acquisition frequency (40000Hz) while also controlling motor movement step by step.  My problem is that when I put the DAQ assistant for continuous samples to 40 kHz it acquires yet the amount indicated in the number of sample area before stopping.  I plugged in a local variable to the stop input, but she seems to have no effect.  Any help would be great.

  -Jake

  N °

  N samples will take samples of N and collect no more until the next time you call it.

  Continuous start collecting samples.  You ask N and he'll wait and turn the N samples once they come in.  Meanwhile, while you do other things in your code, it will continue to collect, N + 1, N + 2, etc. in its buffer.  The next time you come back and call, he'll wait again for the next N samples, but he maybe already all these N, or substantially all of them and will not have to wait that long.  Also, you don't pause in the data because the first sample of N following will be the one that immediately follows the last sample of N first with synchronization of the clock.

• DAQ Assistant does not give me any options trigger

  Once I have configured my DAQ Assistant for acquisition of data and the channel my card, I double click the assistnat and go to the menu of trigger to set the trigger but all the options are greyed out. I use an NI 9215 data acquisition card.

  winterfresh11 wrote:

  Once I have configured my DAQ Assistant for acquisition of data and the channel my card, I double click the assistnat and go to the menu of trigger to set the trigger but all the options are greyed out. I use an NI 9215 data acquisition card.

  That does not surprise me.  There is no way to trigger these devices.  You are sampling whether or not