write waveform in binary

Similar Questions

• Write Waveform files problems

  I have problems using the command 'writing of the waveform to the file. Perhaps the problem lies elsewhere. The problem is that even if the path is correct on my front panel indicator, a file is never created. The path to the file is created by using the location of the folder and by creating the file from the timestamp of the time of execution of the program. I would be grateful if someone could explain a solution.

  Curtis

  Your loop never ends?  This wave function to write to a file is outside the loop, then it won't work until once the loop is completed.

• Continuously measure and write waveform using PDM

  Hi all

  I'm doing my thesis by using Labview 2010 (since this is the only version currently available in University ). I need to read and save data from the microphone (currently to simulate a signal because I need to make the program work first) then save and analise IT (has not reached this point yet). I tried to use the structure of the event in order to record and then play tdms files. But unfortunately it saves only a small piece, then I inserted while loop, so it will record continuously but the program is not responding after registration, I push and I can only manually close the toolbar it. Please does someone could help me or suggest that something since I'm not very good for Labview and any comment is welcome. Here's what I've done so now. I tried searching forums for a similar solution but did not find anything useful (some had a much newer version so I could not open). Thank you.

  Hi and welcome to the forums,

  The reason why you can not stop the waveform recording or exit the application is because you have the case of the events set to "lock the table until the end of the matter for this event" (in edition events). This means that LabVIEW will not respond to the user until the end of this structure of the event, but because you have the option to press the while loop stop to complete the structure of the event means that you have a blockage and abandon the VI.

  The architecture of your application is not ideal - I highly recommend everything that takes a long time to execute within the structure of your event for the above reason (obviously you can uncheck lock as a quick fix Panel). I think I have a look at the design of producer/consumer model (events) (new... > model > frameworks) because it would be more appropriate for your application. You can manage your button presses in the structure of the event and have a state machine in the loop at the bottom for starting, running and stopping of your data acquisition.

  The idea is that you don't do very little inside the event structure so it frees up the façade, but the messages (e.g. power acquisition data, quit the application) are managed by another loop.

  I don't know if it comes in LabVIEW 2010, but there are examples of projects that include a project in 2012/2013 "continuous measurement and logging" which may be suitable for your application. There are also examples of the State machines and managers of messages queued.

• Reduce the size of a file created by "write to waveform.

  Hello

  I'm using labview in 2012 and I have a problem with the size of the tdms file generated by the function "write to waveform. The data is real time 16 channels in a series of X NI USB-6343 and is composed by the gains of the voltage on the y-axis with the absolute time on the x axis (waveform format). The size of the file is reached a Go command within a few hours. Is it possible to reduce the size of this file? All configurations on the component?

  Thanks for the help.

  Best regards

  Marcelo Nobre

  Yes indeed, there is a better way.  Instead of using writing on file express VI measure, try adding the DAQmx logging into your task DAQmx (before starting the task):

  

  This method writes the raw binary data unadjusted to the file (2 bytes per sample because it is a 16-bit data acquisition card) with scaling of information in the header of the file.  In the example you posted, you write the data which are already put across to the file (double 8 bytes for example).  What will make this change you expect to reduce your file size by ~ 4 x.

  If you wish you can compress the files once you have finished writing to them for further reduction of size, but there is no support to achieve so that you are currently writing in the PDM file.  In addition, you will need to unzip the file until you can access the data in the .tdms file.  You can probably get good results with something as simple as the data stored in a .zip file.

  Best regards

• Format for writing arrays to binary files

  I try to write to a binary file as a first step to understand how to work the stored formats.

  Currently, I have two vi, one writes a unique double in a file, and another writes a double 1 d table to a file.

  When I read these files in MATLAB, observing the correct format, I have successfully recover my double scalar single, but not the array of doubles.  The table comes from 10000 samples of a waveform of sin.  I observe that the sine wave output is correct via a waveform graph, and a graph shaped wave plugged into the values Y of the sinusoidal waveform.

  I use the same commands in MATLAB for both:

  FD = fopen ("output.bin', 'r', 'b');

  entry = fread (fd, inf, 'double-online double');

  fclose (FD);

  Attached are two variants of vi.

  By default, LabVIEW wrote the size of the array in the first bytes of the file. I'm not sure if MATLAB interprets this size information. Write to a binary file has an entry for controlling the economy of size information.  Try a wired False Boolean value for "precede the array or string of size?

  Lynn

• Acquired two binary channels.

  I apologize if it's incredibly simple, but I seem to be at an impasse. My goal is simple. I want to use Labview to gather acoustic data (sampling at 50 k per channel) since a DAQ card two channels of NOR. I would like to pass these two strings in binary files (one file containing both channels, or one file per channel). Next, I want to be able to use a separate vi to open these files and convert data into .wav (or anything, really; .wav seems appropriate for the acoustic data).

  My problem is that the 'write waveform in the file' tends to create very large files that cause memory problems when opening.

  I tried several variants of use write a binary and reading binaries that have given rise to very mixed data.

  Any help would be appreciated.

  What about using intermediate tdms as binary files? they are standardized, then you do not need to create parser vi-s and have very good performance

  The NI TDMS File Format

• Sync CAN read, CAN write and DAQmx

  Hi all

  I have setup an application with a cDAQ 9178.  I have several digital and analog i/o cards and a BOBBIN card in the chassis.

  The unit is used in a hydraulic test bench.  I'm reading and writing of my analog equipment and digital I/O timed and synchronized.

  I also managed to synchronize my CAN read waveforms with my entry analog daqmx and so sync CAN read with DAQMX.  I used one of the examples in the finder of the example to handle this.  Now I want to synchronize my CAN write waveforms with my CAN read waveforms and so also with analog and digital DAQmx tasks.

  Are there examples where using the API OR-XNET which shows how synchronize CAN read waveform and CAN write waveform on the same interface?

  I tried to read my signals output by adding them to the list of signals of the CAN read signals, but they did not show.

  Thanks & best regards,

  Lieven

  Hi Simon,.

  I have the module 9862 in my chassis and have managed to use the trigger for the start of my NI9205 analog input card to synchronize my readings CAN with all my other analog I/o.

  Now, I just wanted to see my CAN output signals synchronized with the rest of the signals.  At first, I tried to use the same trigger for my BOX of output on the map, but somehow, it did not work properly.  After looking a little on the forum and in the examples that I found a knot of XNET SESSION property called EchoTX and used on my BOX of exit session.  I then added my output signals to my list of input signals and was able to read my output signals.

  That's what I was looking for.

  Thank you

  Lieven

• DAQmx read - the values on the scale or not? Binary conversion.

  Hey everybody,

  I had a question regarding making the scale and the release of Renault. I use LabVIEW 2009 SP1, with a pilot DAQmx 9.0.2 and a X-Series card. I'm reading the data my DAQ and store it in a binary file.

  How is the acquisition of data read samples, in General? that is if I select NSamp NChan I16 2D Analog on my DAQmx Read, what kind of values can I expect if I was at the exit of the probe data? (Suppose I have readings in mV values and my overall fork's 04:55 V.) When he wrote in the binary file, what happens, what can I expect to see in terms of values - or maybe just descriptively?

  Overall, a little insight would be very helpful. I tried to troubleshoot asymmetric readings I received, so this will help me immensely.

  Thank you.

  Hi Matt87,

  Reading data as I16 will return the result adjusted, not calibrated for 16-bit ADC.

  If you want to write your own binaries, you'll want to include scaling of device - for series X, coefficients a 3rd order polynomial.

  Here are two examples that show how write to a binary file and read the data back.  In this example, scaling coefficients are stored in the file header:

  Continuous gain and voltage drop (binary) chart

  Graph of the acquired binary data

  That said, I would recommend that you look in the record feature integrated TDMS introduced in DAQmx 9.0.  The result is a file appropriate binary .tdms which is a standard format that can be opened in LabVIEW or in several other programs with the plugin.  See the following examples for how to use the function:

  Streaming data and log to the PDM file

  Continuously to log in a PDM file data

  The second example does not force you to read the data in the memory of LabVIEW and use the minimum CPU.  The first example allows you to see the data that is acquired.

  Best regards

• 1 table D of waveform DBL file or its

  Hello.

  I am building an application where I have an accelerometer with an interface USB-1208FS samples.

  I have this loop on the inside with a few virtual instruments to display the waveform and frequency of it components. I tried many different approaches to record in a file, but it doesn't seem to work. No file is created even although I am administrator.

  Data that are fed to the filters and these great are "table 1 d of waveform (DBL). Tried to convert other types of data, but does not work. This VI for example 'write waveform of File.VI' does nothing even if it should accept this type of data. It's "waveform table is a 1 d table the you want to write to a file of wave forms.»

  I'd appreciate any help on my way to accomplish this task. With regard to Abraham

  You still have not posted this VI. You say exactly what function and it is inside the loop / out of the loop that wants to say? My only guess is that you use the button stop in the toolbar.

• You want to read binary files in some parts of the 500th row in the 5 000th row.

  I have files of 200 MB of 1000561 lines binary data and 32 columns when I read the file and sequentially conspire full memory of the generated message.

  Now, I want to read the file in pieces as the 500th row 5,000th row with all the columns and it draw in the graph.

  I tried to develop logic using functions file advanced set file position and the binary file reading block, but still not get the sollution.

  Please, help me to solve this problem.

  Thanks in advance...

  Hi ospl,.

  To read a specific part of the binary, I suggest to set the file position where you want to read the data and specify how many blocks you must read binary file for reading binary file.VI

  for example, if you write table 2D binary file, and then mention you data type this 2D chart and make your account (5000-500). Then together, you produce position. If you have 32 DBL data type and column then it is 256 to the second row and 256 * 500 for line 501th. Use this number as input into your position.vi file get.

  I hope you find you way through this.

• What is the best way to read this binary file?

  I wrote a program that acquires data from a card DAQmx and he writes on a binary file (attached file and photo). The data I'm acquisition comes 2.5ms, 8-channel / s for at least 5 seconds. What is the best way to read this binary file, knowing that:

  -I'll need it also on the graphic (after acquisition)

  -J' I need also to see these values and use them later in Matlab.

  I tried the 'chain of array to worksheet', but LabView goes out of memory (even if I don't use all 8 channels, but only 1).

  LabView 8.6

  I think that access to data is just as fast, what happens to a TDMS file which is an index generated in the TDMS file that says 'the byte positions xxxx data written yyyy' which is the only overload for TDMS files as far as I know.

  We never had issues with data storage. Data acquisition, analysis and storage with > 500 kech. / s, the questions you get are normally most of the time a result of bad programming styles.

  Tone

• VI Scripting VISA Write / Read

  Hello

  I am using VI scripts to change the setting of the context menu for a node GPIB write or Read GPIB - Mode of e/s synchronous. I get the reference to the node GPIB write , but when I try to use the ToMoreSpecificClass function with the target GPIBReadWriteclass, ToMoreSpecificClass returns an error 1057: LabVIEW: Type mismatch: object cannot be cast to the specified type.

  I tried the same thing with the function write into text file . It also has a context menu setting for convert EOL. Trying to convert his reference with ToMoreSpecificClass function with the ReadWriteFile of the target class causes the same error: 1057 Type Mismatch.

  What Miss me?

  Hello

  Members, I found were "binary file read" and "write to the binary file. I have attached a simple script how to find all the possible functions of a certain class.

  Just to clarify: since VI scripting is not an official member of LabVIEW is not a 'problem' in the strict sense. VI script provides the helper function that can be used if it is present.

  Best regards

  Christoph

• binary continuous record and then converted to the spreadsheet

  Hello

  I'm trying to save time without interruption loop of stamps in a binary file with each iteration of a while, and then when the code is stopped, I would like this file converter to a csv file.  I have an application problem, could someone point out where I'm wrong, thanks!

  Check out: How to write and read binary files

  'precede the size of table or chain' must be = TRUE on the binary writing.

  I don't know why you want to save as a 2D single element array.  A simplified version is attached.

• How to convert the pixels of a binary PNG files in codeles folder

  Hello

  I am trying to convert the pixels of the PNG file in binary code and I have to do it for a folder full of PNG files. At the moment my home VI information from PNG in a cluster and then convert the color RGB pixels and then write them in binary. The problem is that it do so for only one way.

  Is it possible do automatically all the PNG files in the folder?

  If you need to make the existing logic for all the .png files in a folder (list the .png files and use build path in order to frame a picture of path all the png Files and then place your existing logic in a loop)

• Backup error of waveform of 380 TDS in spreadsheet

  Hello

  I tried to record the signals generated by TkTDS 3xx read Waveform.vi a worksheet or Excel. I tried to use "write waveforms to file.vi.

  However, this error was encountered, ""you have connected 2 terminals of different type. " The type of the source is a cluster of 3 elements. The sink type is double of waveform. Therefore, I was wondering how to record the cluster of 3 elements to a worksheet? »

  The vi that I was working on is attached.

  Help, please.

  Thank you

  Hi Wan81,

  Yes, the heat exchanger of the method by Dennis Knutson is right. Please refer to the image below:

  

  If you want to write data in clusters, you can use the files Datalog. However, please consider to make, if you want to return to read or manipulate with LabVIEW ONLY . If you want to learn more about the files Datalog, you can refer by using LabVIEW as follows: Help files Datalog

  Please let me know if this solution works for your application or not. Good day!

  Sincerely,

  Krisna Wisnu

  Application engineer

  NEITHER ASEAN