DAQmx writing doesn't 'follow' entry

Similar Questions

• Daq stop task VI back to the State of the task was really forward the DAQmx Start Task or DAQmx writing?

  Hello

  I use DAQmx and DAQ Assistant and try to get the details on the following questions.

  1 does Daq stop task VI really return to the State of the task is in front the DAQmx Start Task or DAQmx writing? Digital Input taking as an example, I don't think that the status of the task means that input data because I tried and I can't really back to the entry level it was.

  Maybe more experienced people can help to share their expertise.

  2. the information in help indicates "virtual channels created with the function/VI DAQmx create Virtual Channel are called virtual channels the and cannot be used in the task." But I don't know what "in his work" means.

  3. could I get some guidelines or expertise on the Labview programmers when use virtual channels the and when, to the more global?

  Thank you!

  Best regards

  Allen

  If you create a channel of the task, or scale just usuing the screw to create or Assistant session wire io is the only way to pass the info autour.  It is not saved anywhere on the disc.  A channel of the task or the scale in a project can be used by anything in this project.  A channel of the task or the scale recorded in MAX can be used by anything on this machine.  Its an extended thing.

  And Yes, the DAQ Assistant fresh extra performance overhead and the poor than the DAQmx API.  Often, it won't have the impact of a little experiment.  Large applications should avoid the express Visa.

• The substitution of DAQmx writing?

  Hello

  In my project, I am required to constantly acquire an analog input of 2 sensors and den generate the desired to 2 devices using use-cases(already done) output.

  The question now is whether it is possible to substitute the DAQmx writing so that I can ignore the use cases and just generate the output I want

  Put a case statement in the case statement, you already have? Is the point to jump DAQmx writing or have a control to set up the output?

  And clean your diagram. The wiring is horrible.

• What do the following entries in the following configuration file?

  What do the following entries in the following configuration file?
  Thank you
  < include > coherence-pof - config.xml < / include >
  < allow-interfaces > true < / allow interfaces >
  true < subclasses allow > < / subclasses allow >
  

  <?xml version="1.0"?>
  <!DOCTYPE pof-config SYSTEM "pof-config.dtd">
  <pof-config>
  <user-type-list>
  <!-- coherence POF user types -->
  <include>coherence-pof-config.xml</include>
  <!-- com.tangosol.examples package -->
  ...
  <allow-interfaces>true</allow-interfaces>
  <allow-subclasses>true</allow-subclasses>
  </pof-config>

  -L' allow-interfaces to indicate if the class name of the type of user can specify types of Java interface in addition to the Java classes. Valid values are "true" or "false". Default value is false.

  -L' allow-sub-classes element indicates if the user-name of the class type can specify a type of Java class which is abstract, and whether subclasses of any type of user specified name of the class will be allowed during execution and automatically map to the super class specified for a serializer. Valid values are "true" or "false". Default value is false.

  -L' user-type-list element contains zero or more elements of type of consumer. Each type of user POF that is used must be included in the list-type-user. The item of list-type - the user can also contain zero or more include items. Each includes element is used to add items of type user defined in another pof-config file.

  The include element specifies the location of a pof-config file to load items of type user of. The value is a string of locator (URL or a valid path) that identifies the location of the target pof-config file.

  http://wiki.tangosol.com/display/COH35UG/user-type-list

  http://wiki.tangosol.com/display/COH35UG/POF-config

  Thank you

  Everett Williams
  Team coherence

• Can you have multiple nested DAQmx writing VI?

  Hello everyone. I'm pretty new to Labview and am trying to find the best way to manage several instructions 'if' using a table of clusters and outputing to the various pins on a data acquisition module. Going to work to have a dozen DAQmx live write in the nested case statements, or will it cause errors?

  The goal is to take the entries by the out of control and front panel based on schedules and user input values. Any suggestion would be appreciated.

  I thank very you much in advance!

  James

  Of course, you can have several writing VI DAQmx.

  Here is a tip that will save programming time you:

  The Index Array feature is re-sizable!  You don't need to break a wire table and 4 tables to Index and thread of the constants for each of them to get the individual items.  Just drop a, and then drag the bottom of the knot to the bottom until you get 4 outputs.  By default, they start at 0 and increment by 1 when you get off.  You will get the elements 0, 1, 2, and 3 without having to associate the constants to the index entry.

  I also recommend that, instead to use local variables, you keep the table of boolean in a thread that runs through all cases in a shift register.  Just replace the item array for any element of the array you are editing in a particular case.

  I have also modeled the code, you have no need for dozens of instructions box nested.  For example, you have one ON and OFF cases in one of the nests.  I'm assuming that the only difference is that you are wiring is real or fake.  Wiring just the Boolean value.  Various other code is duplicated between each case.  The same for the upper levels of the nest.  If you write to the acquisition of data in all cases, who move outside the structure of the case and just control what Boolean values to change the Interior structures of the case.

• DAQmx writing

  Hello

  I am trying to simultaneously acquire a signal while generating / writing a signal chirp (swept sine wave), which varies from 0 to 800 Hz. before, I was able to do it using a loop timed with 1 KHz clock and 100 msec period. The sampling rate for the moment for generation DAQmx was 4000 Hz, and the number of samples per channel was set at 400. In the timed loop samples per channel for the DAQmx write that VI is set to 400. I used "Creat an analog Signal" express VI into the loop timed to generate the beep signal using a 4000 Hz sampling rate and number of samples of 400. The FFT of the acquired signal was clean with almost no noise inside.

  Now, I changed the above parameters such as the VI can be used for real-time closed loop control. So I reduced the samples per channel in all cases to 1 and use the clock 1 MHz with 200 micro-sec period, acquisition and generation at 4000 Hz. However, evaluating the acquired signal FFT, I realized that it contains a lot of noise, while the previous code with 400 samples per channel contained no noise for a frequency to 1000 Hz band.

  I think that the problem comes from the high sampling rate with the small number of samples per channel for the writing VI DAQmx. My feeling is that the DAQmx doesn't have enough time to write all of the samples in the buffer. I tried different values for the timeout for DAQmx VI (reading and writing DAQmx) in the timed loop, but it did not work... I gave the last VI here. Can someone help me where the problem is?

  Also, is it possible that I can monitor the actual values of the data written (i.e. the output of writing DAQmx)?

  Thank you

  You mentioned the loop is expected to completed in 330 microseconds. If it is not designed to finish at 200 microseconds based on the period of your timed loop? It would be the best way to control real time loop to connect an indicator to the duration of the iteration inside the timed loop.

  It seems that you have configured your VI DAQmx of Timing to get a sampling rate of 4000. You then write a signal with respect to 12000 s/s from the node to create an analog Signal. I recommend you keep these two consistent values. If you are wanting to read/write data at 4000 Hz, which would be linked to a period of 250 microseconds. You can increase the length of your timed loop 250 or more.

  You can attach a screenshot of some data that you had who had less noise for comparison purposes?

• Problem writing data analog and entry of informed

  Hi, I created a labview program that acquires 3 analog inputs (2 current and 1 tension), encoder out of whack angle and 4 temporary sensors. The Analogue inputs record against lunatics of an engine angle, once the engine has reached the point dead high simulateously in a single file. In another temperature record since signals file they are a lower sampling rate. Both files at the same time record by using the structure of flat sequence to the duration of the pulse encoder TDC events. The program works well with simultaneous recording.

  However, I believe that in the file of analog inputs, the current readings are by crank angle but channel voltage readings are not. There a lot of zeroes inbetween pressure readings as if DAQ is not intervene for the tension. I can't understand why my program does that because the analog all the readings are in the same time of the sample and analog read the task.

  I tried a program separate labview using only express DAQ and have the same 3 channels and saves the data in a file of lvm - it works even at the same pace. I do not wish to use Express functions in my program since fast flow and writing, he will miss values due to the explicit functions opening and closing of files (explicit writable) and creating the same physical channel (in daq express).

  Please can someone help?

  I have attached my program and a sample file entry.

  Thank you very much

  Notay

  I think your problem is that you are indexing column 2 for voltage instead of rank 2. That's why you have only three elements in this table in the cluster.

• What channel DAQmx property corresponds to "name" entry "DAQmx create Channel.vi?

  Hello people,

  I am changing a program, I have inherited so that it uses DAQmx virtual tasks rather than have the task and the channels created by programming of in the code.

  In the existing code, the entry 'name' on the 'DAQmx create Channel.vi' is wired with a value.  When you use a virtual task DAQmx, I do not use the 'DAQmx create Channel.vi', but I still want to set the values of the "name" in the code with the help of a property DAQmx node.  However, I can't find a property called "name".  Such a property exists with a different name?

  Best regards

  Chris

  
  

• Tracker mask doesn't follow the movement

  Hello.

  After 14 effects using, I want to hide a moving person in my shot (the camera is stationary), but hide manually (point by point, frame by frame) is a lot of work and track movement does not really work. The problem is that I need to cut the person accurately, but all means of monitoring, I tried were too loose, does not follow the person correctly or has worked better than expected, but just for the face.

  An image says is attached

  I already thank you for your help.

  Sincere greetings,

  

  I fear that you are looking at Rotoscoping.  There is no way to do this without a lot of work.

  You could start with tutorials on the rotobrush, like this tool: Adobe after effects CS5-rotoscope with Rotobrush - YouTube

• Foundry camera Tracker doesn't follow 2 frames?

  After some time, do not use foundry, it seems suddenly only to follow the 2 images. I just know that the video was made has decompressed in sony vegas 12. But I don't think that this has nothing to do with that well.

  If you encounter a problem with The Foundry Camera Tracker, I recommend asking the Foundry:

  Support | The Foundry

• U8 NChan NSamp 2D DAQmx writing question: Digital

  The help file says that for the "Digital 2D U8 NChan NSamp' vi, each row of U8s is a channel and each column is a sample. But each sample U8 get extended to 8 bits? If so, what bit is first (MSB or LSB)?

  If this is not the case, how the U8 is sent to the material. Is the U8 a sample of port where each bit value corresponds to a line on a port? If it is this plan, so I guess if you had 3 lines in a channel, 5 bits of the U8 would be unused. I also assume that all lines in a channel would have to be on the same port.

  I guess my confusion comes because I think a somewhat broad digital as channel, while the literature seems to indicate that a digital channel can be composed of several bits.

  I don't have a DAQ DIO to confirm this, but I think the LSB of the U8 goes to port x 0 (D0), line up the MSB goes to port x line 7 (D7).  So if you had 3 lines in a channel, 5 bits of the U8 would be ignored.  Yes, all lines must be on the same port.  If the polymorphic selection is U8, then you must have 8 rows on the same port.  If the U16, two ports are concantenated to form 16 lines that correspond with the U16.

  I too tend to think of a digital channel in one line.  The terminology is confusing.  They shouldn't mention the word of all channel.  It should be ports and lines only, as port 0 line until the line port 0 7 0, then 1 line 0 port and so on.

  The expression "each row of U8s is a channel", I think that this meant that only one channel is the 8 lines of a port.  In other words, the channel is a port.  I guess they use the channel because if you specify U16, a channel could be ports 0 and 1.

• Output broken for writing DAQmx

  Hello

  I need emergency assistance with a problem I have with write DAQmx.  The 'DAQmx write VI' is located inside a while loop that repeats every 20ms.  I use queues to transfer data between several asynchronous VI and the data does not update all 20ms.  Because I'm not going to tie the whole project I faked the timing of 20ms to 'Wait for next ms Multiple' vocation.  What happens is I will send 20ms of data to the VI DAQmx writing, he will have all the data output with 4ms can sit idle for 16ms.  I implemented the task for the DAQmx example 1000 per channel at a rate of 50 kHz, which should take all 20ms to the exit.  I also checked the waveforms of entry the entry have 1 k samples and a detachment of the 2nd-5.  When I went from the DBL 2D table has not changed.  I want to emphasize that all data is sent into the 4 DC.  It's confermed visulaly and with the node 'written examples.

  I did a test where I hosted my VI to run as fast as possible.  In this case, the output was a sine curve, but looking more closely, I found that the output frequency of 25 Hz 5 times faster than the signal that I sent to the writing DAQmx VI.  In addition if you limit the loop to 10ms iterate the data is output for 4ms and the idle 6ms.

  I know that everything is configured correctly.  I rechecked the data I sent you the properties of the task.  She should be out correctly, but it isn't.  I tried calling support NEITHER and he was not particularly helpful.

  The equipment I use is a PXI 6723 AO map.  I will attach a vi that anyone could run and I will attach a picture of the exit on an oscilloscope. Thnak you for the help

  -James

  I solved my problem.  I needed to add a calendar DAQmx and DAQmx writing change the task before entering the while loop.  I use the calendar to set the mode of the sample and the source of the command, while simple DAQmx writing sends and matrix of zeros.  With these added it works very well.

  -James

• Writing DAQmx invoke node leads to a runtime error (R6025 - pure virtual function call)

  I have a request in which a Subvi DAQmx writing calls calling node (shift of writing and reading NumChans).

  When I launch LabVIEW and the main VI a first run, everything works fine. When I run a second time, LabVIEW crashes with a runtime to Scripture DAQmx error call node:
  R6025 - pure virtual function call

  The LabVIEW failure log file contains the following lines:
  c:\builds\penguin\labview\branches\Saturn\dev\source\compiler\allocsup.cpp(662): DWarn: dataspace moved running!
  $Id: //labview/branches/Saturn/dev/source/compiler/allocsup.cpp#18 $

  Anyone has any idea how this accident could be avoided?

  Problem solved: we have just removed the line NumChan (read) from the node to invoke and readded it again. Now, it works fine.

• DAQmx shown writing as broken, carefully read

  I'm trying to do a test day, it was originally at 8.6 and I took it in 11, also I can't work on it on the system where it is running. (it is heavily used)

  I have exported and imported settings MAX from the old system to my system

  the VI indicates the arrow broken and says Scripture DAQmx is broken, but if I open the DAQmx writing it does not show the broken arrow and works fine, no errors.

  I tried to remove and reapply the call to the DAQmx but I get the same error, reading is not the problem.

  I also tried to open a new project, same results, VI with DAQmx write shows the broken arrow, DAQmx only

  the original app written in a NI PCI-6250, which I did not in the my system, if I make a DAQ Assit the 6250 appears, which in my mind means the importation of settign MAX worked, device also appears in MAX, but the DAQ seated VI is also marked as broken by the VI.

  using LabView 2011 SP1 and 9.4 DAQmx, win 7 is the operating system

  someone at - it an idea of what I'm doing wrong?

  Try right-clicking on the DAQmx VI of writing on the block diagram, and then select open VI polymorphic. This will show you all the screws instance and report those that are broken.

  Mike...

• Size of the buffer of size/write DAQmx

  What is the strategy privileged in regards to writing data in the buffer output for a digital output or analog DAQmx?

  I ask this because in the old days pre-DAQmx, you were supposed to flow of data in the buffer in buffer half lengths, so you would write buffer_len samples on the first entry, begin the proofreading work then write half puts in memory buffer on subsequent writing, the idea being that you write half a buffer while the output card has been reading of the other half.

  It doesn't seem to be something to indicate this technique is even longer when you use DAQmx, but he still linger of links that mention the teqchnique.

  What is the way NOR recommended, and if it has changed, why?

  Thank you

  Hi ToeCutter,

  Currently there is no need to think about buffers at a level very down the DAQmx digital to analog output.

  DAQmx handles it for you as soon as you call the function "Write DAQmx".

  

  You can provide data to write DAQmx in a variety of forms (from waveforms and ending with the raw data).

  It may be different depending on the application.

  Please take a look in the manual of DAQmx writing VI:

  http://zone.NI.com/reference/en-XX/help/370469AA-01/lvdaqmx/mxwrite/

  Kind regards