TDMS AnalogWaveForm write c#

Similar Questions

• TDMS first write delay

  I am trying to broadcast a large amount of data to an FPGA Flexrio/ent before continuous scanning to

  disc HDD-8265 continuously. I use the advanced functions of PDM, preallocating the

  size of the file with the correct sector size, etc. and when I listen 2 G - 50 G samples (u32), it doesn't work

  problem.

  As I increse my sample from 2 G to 50 G size, I noticed that the target-to-Host FIFO through which I send

  My data is beginning to be fiulled upward during the first time I try to write the .tdms file. Once the writing is recommended

  is called it firt time, everything is ok and writing advanced catches up.

  I noticed when I exceed 80G samples of the target-toHost FIFO overflow and I lose events. I'm trying to fix this problem; I need to keep all the events which me providning an absolute timestamp (GPS)

  which is generated by a number fixed events since the start of data acquisition. If I drop the events, I lose my ability to TimeStamp any particular DAQ sample.

  I keep my the same sampling rate through the tests, so it seems that the problem is associated with

  Some are looking kind of time of the first entry in the .tdms file; It seems to stretch and longer

  the file is large, then once that he firt writing it is not a problem.  Once the HDD-8265 starts

  write, there is no problem juggling; It's just kind of initialization time-out that is proprtional to the

  the file size is allocated.

  I'm preallocating space using the advanced features of .tdms and tried to put a wait after this function but

  has no effect on the time of the first entry.

  Is it possible to start the HDD-8265 to get ready to take data without actually writing the events? I guess I could write a dummy block of fixed length, wait a second and then select the data acquisition system, but this seems like a terribly stupid thing to do. I would rather not write dummy data blocks for the HDD-8265 just to get rid of the delay until the disk can fully manage the flow of data cointinuous.

  OK, this definitely helps. If you have a large file, say 1 TB, then you will have to wait a few seconds after the flush before the 8265 is ready to take data. It seems that the reader begins to map the allocation of files after the flush.

  I put a delay time of 5 seconds after the flush, and it seems to work perfectly for a 1 TB file. I suspect 5 TB

  should maybe 10s or more. See the joint .png

  I did not consider that you could mix regular functions and advanced .tdms... Thanks for the help!

• How to write data in mode intertwined with TDMS C DLL 2.0?

  Hello

  How to write data in mode intertwined with TDMS C DLL 2.0?

  I use DAQmx features in Visual Studio C++ without Measurment Studio.

  This function returns the data in interlaced mode.

  How can I configure the functions of DLL C TDMS to store this data in the tdms files?

  I see that it is not possible with the PDM version 2.0 with 1.0.

  Thank you

  -TDM C Dll is not able to do

  -TDM header writer may be usable for this but is not able to be used for tdms files.

• Extract strings in the tdms files and write the strings in the file txt or lvm

  Hi all

  I'm struggling to extract strings from a file of tdms to write them in a txt file.

  The strings were written in tdms is a time stamp data recorded to a compact RIO.

  I put the chain in a different group from the PDM, but when I use the function read tdms with the group name, as I said, an error message is always take place.

  Thanks for all the help.

  PS: I have attached an example of tdms file I got over here.

  Kind regards

  Yifeng

  I tried your attached file and it seems that everything goes file. I have attached the screenshot of my VI here, what do you want?

  

• How to build a table of TDMS file open

  Hello

  Examples NI TDMS - Express write data .vi (time domain), I can build a PDM file with 2 channels (sine and square waveforms) data, which are stored as test.tdms.

  Using Express read .vi data (time domain), 2 channels of waveform data are read. How to build a table later? How to separate the 2 channels of data in the tables 1-2 and manipulate the data using table functions?

  For example,.

  I want to collect 100 from index100 between channel 0 and their average. I want to take 50 samples from the channel 50 1 index and double each element.

  Thank you for your help.

  Bing@NCL

  Hey Bing.

  You can perform operations on different channels in the 2D table using the table to index. This will allow you to choose the channel to operate on, then you can perform the operation inside a loop on each element. In the included code snippet, I used a shift register to find the total cumulative values in channel 0 and then divided by the number of samples.

  I recommend you read some tutorials LabVIEW and bases of knowledge on topics that are related to yours. These could help a lot.

  I hope that my suggestions help,

  Chris

• TDMS file creates several tabs data. You want to create only one.

  Hello NOR community,

  I am currently using the DAQ Assistant with my pots of chain record travel over a long time interval (see annex VI). I then use the vi "Write to a file as" to save the data in a file TDMS (see 'Write the file settings' photo attached for all the parameters chosen for the writing of the file). The file is written, however when I open the PDM file, the document creates a tab in Excel for every second of recorded data (please see attachment ""). It seems that the TDMS file is grouping all data every second, and then by creating a new group of data.

  How can I get the file to write all data on a single tab instead of creating multiple? I don't want to concatenate hundreds of tabs in a single great sheet.

  Thank you

  Chris

  You should not use the comment.  I just removed who and everything worked for me.

• TDM/PDM Java interface?

  Hello, someone has developed a Java interface that can read the TOC and PDM files?  Of all the googling and poking around the site of NOR, my hunch is no, but I just wanted to ask you anyway just to be sure. In my opinion, he is a writer of header to Java (http://zone.ni.com/devzone/cda/epd/p/id/6280), questions about the external interfaces (http://digital.ni.com/public.nsf/allkb/A3663DE39D6A2C5A86257204005C11CA) and pre-existing drives C and Excel, but I see no mention of a Java API to read these files.

  Otherwise, I'm looking for confirmation that there was, and whether or not a likely to be developed in the future.  If not, how other people solve this problem?  Using JNI with the C library for the CT (S) data in Java applications?

  Thank you very much for your support.

  Derek

  PS: I didn't know where to post what I did not see a separate category of CT. Thank you.

  Here's a post of "TDM header writer Java API":

  http://zone.NI.com/DevZone/CDA/EPD/p/ID/6280

  If there is no API available for playback, it seems you need to do your own API based file formats, for the PDM, the structure of file format is here:

  http://zone.NI.com/DevZone/CDA/tut/p/ID/5696

• Problem in writing all channels

  Hello
  There are three questions that I want to clarify:
  1, well I tried to acquired data and write to the disk using the TDMS function using the producer-consumer model. But I wasn't able to get all the data from each channel. What could be the possible reason?
  Joint issues are related.
  2, more could possibly replace the VI instead of PDM file writing?
  3, what different Signal (in average mode) compression of point to point VI medium?
  Thank you.

  Neevedit

  For 1. I'm not clear on "not in position to get all the data of all channels".  In your attached VI, you do not give any input channel TDMS name write. By default, it will only create one channel called "Untitled".

  For 2. Yes, you can try to replace the TDMS file VI writing nodes

• How to read/write tdms 2.0 files with the TDM C DLL?

  Hello

  How to read/write tdms 2.0 files with the TDM C DLL?

  How consequently the datas in interlaced with the TDM C DLL mode?

  Thank you

  Confirmation: TDM C DLL always wrote the file in TDMS version 2.0.

• How to merge and write analog inputs, and export data to a tdms file?

  I have a vi who writes analog inputs in tdms files. I also want to write the analog output signals, which are 2d table entries in the same PDM file with additional columns representing the analog output signals. How can I get this feature?

  Ashaironix wrote:

  Hey Crossrulz,

  So you're saying that writing two files tdms with entries as HAVE and AO, will write everything in a file single tdms AOs and Ais?

  N ° you write in the same file, just different GROUPS.  TDMS is a hierarchical data format.  You have the file, group, channel.  Waveform data will actually in the channel data.  But you can have metadata on any level.  So, I do a group I and a group of the AO.

• write with a fixed size tdms files

  Hi guys, I'm stuck with the problem of how to write a series of files tdms with each file has a fixed size of continuous analog sound recordings. Each file is named by the timestamps. The solution that I am trying at the moment is to create a new tdms file all the few seconds (provided) using the PDM open function. This idea implies a case structure for the State. When it is true, the new file name is created and then the open function tdm is called. When it is not true, I would use the name of the file created earlier. However, I do not know how to get the filename that is created previously, and so I'm unable to wire the false conditon of the structure of the case. Any help would be appreciated.

  An excerpt from play with him:

  

  

• Write a new TDMS file hourly

  Hello NOR community,

  Currently, I am trying to write a VI that creates a new file TDMS every hour and CompactDAQ Ethernet chassis moving data folders. Please see the related code. Right now the code only adds the current TDMS file and do not write a new file on the given time interval. I would like for a new file to be created every hour, so that the files do not get incredibly large.

  Also my travel writing not data data anywhere near correct recovery. Right now it seems to collect a point of data per second, where I rate of recovery at 100.

  Any advice would be greatly appreciated!

  Thank you.

  Chris

  1,000 points at a rate of 1000 s/s.  This means that the DAQ Assistant will take 1 second to read the data.  Now, going through the process, you are just to get the first waveform and then take the first point in the waveform.  As a result, you get 1 sample of the 1000 you spent a second capture.

  This is so a few things, I'd say.

  1 replace your graph with a graph.  A graph keeps a history and can directly take the table of waveforms.  There is no need to further add all the data in this diagram.

  2 play with scales in the DAQ Assistant.  You can apply a linear scale to individual channels, eliminating the need for this loop.

  3. use the logging option in the DAQ Assistant (there is a tab just for that).  You can enable the logging of PDM and he will do everything for you.  You can even have cover multiple files based on the number of samples.

  If after all this, your code should be reduced to something like that

  

• Executable file do not write in tdm/PDM files.

  Hello

  I wrote a wrapper around a VI that controls the entries to designed the hardware and monitors the outputs for the prolonged lifetime of testing purposes.  We use compact DAQ for control and data acquisition.  We do not wish to moor a LabVIEW license for six months to run the desired test, I compiled an executable and built an installation program.  Everything worked without problems on a PC with LabVIEW and everything seemed to work well on a PC without LabVIEW with the executable... until I decided it was time to start analyzing the outputs recorded (tdms files).  The application is able to not control my material, no problem, I could see it passes through different States and key measures that I display on the user interface are valid, but the log files are simply cannot be created, not even an empty file.  At the lowest level, the open storage VI [TDM] is called to open or create the file (filename is entered by the user or created with timestamp if he did not) and each 'bit' of data is written by writing data [group of channels] and write data [channel] live on the PC with LabVIEW, the output files are created without problem.

  Did not work with executables before.  How can I start to debug (without installing LabVIEW on the PC in question - and when all goes well when run on a computer with LabVIEW installed)?  Have tried to build the executable with active debugging, but do not know how to "enable" debugging or a walk through as in LabVIEW... or if it's even possible...  I don't get warnings or errors during the race.  Is there something special I need to do in the construction of my executable or installer, particularly writing executables TDMS files?

  Thanks in advance

  -Andy

  
  

• TDMS write memory and VI a remake TDMS API - LV2009

  In June, I posted a question about a memory problem with TDMS write (LV86). - TDMS write memory leak

  • TDMS write memory works similarly in LV 2009? LabVIEW creates a growing buffer to contain the index with each entry?
  • What is the format of the API of VI for TDMS files writing to write in LV2009? 1.0 or 2.0?
  • For 'TDMS write memory', it has the same behavior in LV 2009.
  • For the VI API, file format in 2009 is version 1.0 and 1.0 files still work fine with LV 2009.

• TDMS write memory leak

  I use TDMS to store test data that seems to be causing a memory leak in my (very convincingly) program. Below is a graph of the three versions of my program. Series 1 uses storing data open PDM, the data file added and closed every 5 seconds. Series 2 uses storing data PDM with a referense remaining open during operation and closed at the end 3 series written data in a CSV file. The charts show the use of LabVIEW memory each seconde.5 ~ 4 hours of a 10 hour test.

  LabVIEW 8.6.1

  Windows XP SP3

  

  Further explanations... when a TDMS file is opened, LabVIEW will create an index in memory structure that is used for random access to the file. The Streaming API integrated LabVIEW TDM will always create the index, even if you just write. The size of the index is not dependent on the size of the file, but on how fragmented file is. If you store a relatively small number of large blocks of data, the index will be very low. If you keep adding small amounts of data on your record, it could make big enough. A cure for this is the property of NI_MinimumBufferSize. You can set this property on a channel to the LabVIEW to a number of values of the buffer before storing. In this way, data from multiple calls to 'Write TDMS' counts as a data segment in the file. Typical values for this are 1000 or 10000. Fragmentation of files and memory footprint are reduced accordingly, but LabVIEW uses little memory for buffers.

  If all else fails and you do not have access to the file of reading while you write, you can also use the VI-based TDMS API. This will not build the structure of the index that I mentioned above, so there should be no increase in memory at all. In this case, I recommend to defragment files front of post-processing.

  Hope that helps,

  Herbert