NIDaqmxbase reading VI until the challenge buffer empty

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• Smart way to save large amounts of data using the circular buffer

  Hello everyone,

  I am currently enter LabView that I develop a measurement of five-channel system. Each "channel" will provide up to two digital inputs, up to three analog inputs of CSR (sampling frequency will be around 4 k to 10 k each channel) and up to five analog inputs for thermocouple (sampling frequency will be lower than 100 s/s). According to the determined user events (such as sudden speed fall) the system should save a file of PDM that contains one row for each data channel, store values n seconds before the impact that happened and with a specified user (for example 10 seconds before the fall of rotation speed, then with a length of 10 minutes).

  My question is how to manage these rather huge amounts of data in an intelligent way and how to get the case of error on the hard disk without loss of samples and dumping of huge amounts of data on the disc when recording the signals when there is no impact. I thought about the following:

  -use a single producer to only acquire the constant and high speed data and write data in the queues

  -use consumers loop to process packets of signals when they become available and to identify impacts and save data on impact is triggered

  -use the third loop with the structure of the event to give the possibility to control the VI without having to interrogate the front panel controls each time

  -use some kind of memory circular buffer in the loop of consumer to store a certain number of data that can be written to the hard disk.

  I hope this is the right way to do it so far.

  Now, I thought about three ways to design the circular data buffer:

  -l' use of RAM as a buffer (files or waiting tables with a limited number of registrations), what is written on disk in one step when you are finished while the rest of the program and DAQ should always be active

  -broadcast directly to hard disk using the advanced features of PDM, and re-setting the Position to write of PDM markers go back to the first entry when a specific amount of data entry was written.

  -disseminate all data on hard drive using PDM streaming, file sharing at a certain time and deleting files TDMS containing no abnormalities later when running directly.

  Regarding the first possibility, I fear that there will be problems with a Crescent quickly the tables/queues, and especially when it comes to backup data from RAM to disk, my program would be stuck for once writes data only on the disk and thus losing the samples in the DAQ loop which I want to continue without interruption.

  Regarding the latter, I meet lot with PDM, data gets easily damaged and I certainly don't know if the PDM Set write next Position is adapted to my needs (I need to adjust the positions for (3analog + 2ctr + 5thermo) * 5channels = line of 50 data more timestamp in the worst case!). I'm afraid also the hard drive won't be able to write fast enough to stream all the data at the same time in the worst case... ?

  Regarding the third option, I fear that classify PDM and open a new TDMS file to continue recording will be fast enough to not lose data packets.

  What are your thoughts here? Is there anyone who has already dealt with similar tasks? Does anyone know some raw criteria on the amount of data may be tempted to spread at an average speed of disk at the same time?

  Thank you very much

  OK, I'm reaching back four years when I've implemented this system, so patient with me.

  We will look at has a trigger and wanting to capture samples before the trigger N and M samples after the outbreak.  The scheme is somewhat complicated, because the goal is not to "Miss" samples.  We came up with this several years ago and it seems to work - there may be an easier way to do it, but never mind.

  We have created two queues - one samples of "Pre-event" line of fixed length N and a queue for event of unlimited size.  We use a design of producer/consumer, with State Machines running each loop.  Without worrying about naming the States, let me describe how each of the works.

  The producer begins in its state of "Pre Trigger", using Lossy Enqueue to place data in the prior event queue.  If the trigger does not occur during this State, we're staying for the following example.  There are a few details I am forget how do ensure us that the prior event queue is full, but skip that for now.  At some point, relaxation tilt us the State. p - event.  Here we queue in the queue for event, count the number of items we enqueue.  When we get to M, we switch of States in the State of pre-event.

  On the consumer side we start in one State 'pending', where we just ignore the two queues.  At some point, the trigger occurs, and we pass the consumer as a pre-event.  It is responsible for the queue (and dealing with) N elements in the queue of pre-event, then manipulate the M the following in the event queue for.  [Hmm - I don't remember how we knew what had finished the event queue for - we count m, or did you we wait until the queue was empty and the producer was again in the State of pre-event?].

  There are a few 'holes' in this simple explanation, that which some, I think we filled.  For example, what happens when the triggers are too close together?  A way to handle this is to not allow a relaxation to be processed as long as the prior event queue is full.

  Bob Schor

• Empty the USB buffer

  We use VISA usb for a USB from our data.

  Everything seems to work properly, we can read and write to the thin device.

  We run into a problem however: If we lose the connection with the device, until we read all the bytes in the RX buffer and close the device, these bytes is achieved when we re-open the device.

  VISA flush doesn't seem to work on USB (like all the 4 predefined masks are refised). Clear VISA does not seem to help either.

  What is the right way to empty the remaining USB unit bytes when you open the interface of bulk VISA usb?

  Serge.

  Well, if VISA Clear does not work and, the bytes to port doesn't work we'll need to dig into the manual for the device at the other end and see how bad some massacred FW engineer a simple message base protocol series and what is really supported by the device.

• Hides read or write the buffer cleanup interval in vSAN 6.0

  For how long data remains in the CACHE/buffer in vSAN 6.0?

  Good afternoon, it will stay in the memory write buffer until it is deactivated on the level of ability.  He will stay in the read buffer until it is full and the oldest bits will be deleted.  Thank you, Zach.

• Read data larger than the DB buffer Cache

  DB version: 10.2.0.4
  OS: Solarit 5.10
  
  
  We have a DB with 1 GB for DB_CACHE_SIZE. Automatic shared memory management is disabled (SGA_TARGET = 0).
  
  If a query is triggered on a table that will grab the 2 GB of data. Hang in this session? How oracle handles this?

  Tom wrote:
  If the recovered blocks get automatically removed from the buffer cache once it is retrieved by the LRU algorithm, then Oracle must handle this without any problem. Right?

  Yes. No problem in that the "+ a fetch size +" (for example, by selecting 2 GB with a value of lines) need to fit completely in the db (only 1 GB in size) buffer cache.

  As mentioned Sybrand - everything in this case is emptied as blocks of data more recent will be read... and that emptied shortly after thereafter as of the even more recent data blocks are read.

  The ratio / access to the cache will be low.

  But this will not cause Oracle errors or problems - simply that degrade performance as volumes of data being processed exceeds the capacity of the cache.

  It's like running a very broad program that requires more RAM which is available on a PC. The 'additional RAM' is the file on the disk. The APA will be slow because its memory pages (some disk) must be swapped in and out of memory as needed. It will work faster if the PC has an enough RAM. However, the o/s is designed to address this exact situation that requires more RAM than physically available.

  Similar situation with the treatment of large chunks of data than the buffer cache has a capacity of.

• I sent an email to someone by mistake, how to retrieve the email until the receiver reads?

  I sent an email to someone by mistake, how to retrieve the email until the receiver reads?

  I sent an email to someone by mistake, how to retrieve the email until the receiver reads?

  You can not. It's like putting a letter in a physical mailbox. There is no way to recover it.

• Has anyone invented a way to get the emails that went to the wrong email address until the wrong person reads?

  Has anyone invented a way to get the emails that went to the wrong email address until the wrong person reads?

  To answer your question, you have to assume that once you have sent the email that it cannot be recovered. Think of it as dropping an old letter in a message box - you can't get it back once it is in the message box.

  The reasons are not only technological - it security, privacy, legal and political might be too (e-mail can cross multiple international borders).

  One hand practice also, what you want would be difficult because the emails will usually quickly reach their destination server and so can be collected by the recipient of email from this server as soon as sound here.

  By ensuring that you are writing your emails correctly in first place is the best.

• ar windows 7 compatible Adobe export sa att pdf med spinning until the word excell och konverteras kan I have Acrobat Reader DC?

  1 ar windows 7 compatible Adobe export sa att pdf med spinning until the word excell och konverteras kan I have Acrobat Reader DC?

  2 hur lang ar bindningstiden for prenumerationen pa Adobe export och hur langt I Maste marxister man saga upp abonnemanget om man inte vill ha kvar det?

  3 kommer uppdateringar att leverera automatiskt eller skall man maybe pa Nagot meddelande som skickas till en for uppdateringar och vet man att det ar fran Adobe och inte natfiske hur?

  Immortalized med Eva E halsning.

  Hi evamarta,

  Yes, you can use Adobe PDF Export using Acrobat Reader. Export PDF to Acrobat Reader DC service using Acrobat Reader DC Acrobat Reader DC Learn & Support on Windows 7.

  You can opt for the monthly or annual subscription export to PDF to Word or Excel online | Export of Adobe PDF

  Once you click on & allow the update to Acrobat Reader DC, it will update. However it has nothing to do with your subscription to Adobe export in PDF format. It's just the update.

  Kind regards
  Nicos

• I'm on Windows 10. A works fine until the update. How can I make Adobe Acrobat Reader (free verision) my default DC? Seems that the default value is E pdf and when I change the default in the flashes of screen reader and forms are in the same format. I ha

  I'm on Windows 10. A works fine until the update. How can I make Adobe Acrobat Reader (free verision) my default DC? Seems that the default value is E pdf and when I change the default in the flashes of screen reader and forms are in the same format. I rather Acrobat format if possible. Thank you

  Hello

  Could a right click on the PDF file > open with > choose program by default and select CD player as default PDF Viewer.

  You can do it from the control panel as well.

  This would make CD player as default PDF Viewer.

  Concerning

  Sukrit diallo

• I finally got CS2 installed on my system. But now the menu background color is black and the elements are not visible until the cursor is over them. It is very difficult to read. How can I change this?

  I finally got CS2 installed on my system. But now the drop-menu background color is black and the elements are not visible until the cursor is over them. It is very difficult to read. How can I change this? I tried to go into change preferences but it does not work

  I changed it to the value default them and that worked. Thank you very much

• I have adobe Premiere elements 13. It will not let me delete audio or do fade in or out. I can move the yellow to the bottom line until the volume reads - 0.0, but the noise is still there during playback. I can click on fade and fade out and the yel

  I have adobe Premiere elements 13. It will not let me delete audio or do fade in or out. I can move the yellow to the bottom line until the volume reads - 0.0, but the noise is still there during playback. I can click on fade in and fade out and the yellow line that chart volume takes a strong recovery or dip at the beginning or at the end of the clip, but there is no change in volume when I play back. What I am doing wrong?

  Rickey

  Thanks for the follow-up report.

  Just a lit bulb. Maybe the answer, maybe a spleen.

  Look carefully at the audio track of the timeline in the vicinity of title of the file.

  

  The title of your file audio timeline shows: level of Volume or something else. If something else, click the tiny triangle where

  the red arrow in the screen shot is sharp and select the Volume and then level so that you end up with

  Volume: level as shown in the screenshot.

  Hope it's the factor involved.

  RTA

• I have a Dell Inspiron 1545 and I can't download Adobe flash or Adobe acrobat reader, when I try to play my games it says upgrade from flash and when I try to download it on the screen comes empty

  I have a Dell Inspiron 1545 and I can't download Adobe flash or Adobe acrobat reader, when I try to play my games it says upgrade from flash and when I try to download it on the screen comes empty

  Try offline installers:

  • Flash Player ActiveX (Internet Explorer)
  • Flash Player plug-in (all other browsers)

  For Adobe Reader: http://get.adobe.com/reader/enterprise/

• I'd do the signature field read only until something is entered in the required fields.

  I'd do the signature field read only until something is entered in the required fields.

  Attached a sample file that has two text fields and field of signature, the signature field allows only when certain values are typed in two text fields.

  Steps to achieve this:

  (1) disable the signature field when the form is loaded

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• Research within the buffer to the client in the OSMF player empty the buffer to the client

  Hello

  In one skin for OSMF player I have seen that when we seek bar then load and current bar the two becomes equal to the point of pick up and he starts again seek point if loaded bar loading was first superior of the current bar.

  In other words, I can tell when we perform the search operation then bufferLength becomes 0 and start buffering once more from the point of pick up but if we are looking in the memory buffer to the client why must she do bufferLength 0 and empty the old data that has already been buffered.

  Anyone has idea about this issue.

  Kind regards

  Amit

  Yes, that's correct. The event you want to play can be MediaPlayerCapabilityChangeEvent.canPlayChange.

  -Zhang Wei

  Senior computer scientist

  Adobe Systems, Inc..

  [email protected]

• The data buffer series before transmitting

  Hello, I'm relatively new to LabVIEW and had a question about how buffer data to the serial port before transmitting. I've attached what I have so far for a VI, and that's how I expected to work.

  1. Read in hexadecimal string (example: 001122334455)
  2. For loop repeats for half the length of the chain because I am transmitting into blocks of size bytes (example: 6F)
  3. Read the first byte of the ascii string and converts it to hexadecimal equivalent byte and transmits.
  4. Repeats until the chain is completed.

  Basically, I need to place a buffer that fills up my time loop ends then all the data at once. At the moment there is enough of delays between each loop causes errors.

  Any suggestions?

  everettpattison wrote:

  Basically, I need to place a buffer that fills up my time loop ends then all the data at once. At the moment there is enough of delays between each loop causes errors.

  Do you mean the while loop or loop for? In the picture, you put the note that you need a buffer inside the loop for, loop not quite awhile. The amount of calculations going on inside this loop is so small that I can't imagine how it is at the origin of the delays, but you can easily replace it to transmit an entire string at a time. Put Scripture VISA outside the loop for. wire the output channel of the conversion at the border of the loop for, creating a tunnel. Connect the output of this tunnel to concatenate strings, which will combine an array of strings into a single string. Then connect to the entry VISA.

  EDIT: even better, get rid of the conversion, the U8 to wire directly for the edge of the loop, use the byte array to a string to be converted to a string, send this string to Write VISA. There is probably an even easier approach, but I'm not looking too carefully.