Producer-consumer - acquire and analyze different number of samples

Similar Questions

• Different output meter with a different number of samples

  I m using a calendar 6602 i/o Board or a MIO 6281. For controlling the distribution of our measures, I use different counters of two boards that have been triggered by a Digital Out for synchronization. The counters are made CO Pulse Time, implicit, digital synchronization triggered and the sample mode finished.

  Suppose I use two Ctr´s to map 6602. My problem is when you set the number of samples of only CTR for another value, then the second I m getting an error. The rest works perfectly, I can use different delays in starting, low or high times, only samples different amounts Don t work. It s without worrying if I use the Timing of e/s or Multi i/o Board.

  For example:

  _ _       _ _

  CTR 0 / 6602 _ |     |_ _|     |--> _ _ 2 samples

  _ _

  CTR 1 / 6602 _ |     |_ _

  Someone an idea or a tip?

  Hello

  two counters are used for a generation of fenite impulses. Please see the link below.

  Link:
  http://digital.NI.com/public.nsf/allkb/9D1780F448D10F4686257590007B15A8?OpenDocument

  For example, you can use Ctr0 and Ctr2.

  Concerning

  Rüdiger

• First try the producer consumer Architecture: continuous play and dynamically update settings.

  Hello

  I am currently working with two instruments; an Agilent E3646A and a NI 6212 BNC. My goal is to have the 6212 continuously take measures according to predefined parameters while the E3646A parameters can be continuously updated. This combination simple instrument aims to help me learn the manual architecture; continuous measurement, output dynamic controls and instruments more will be added in the future.

  I've already posted on a similar, but more complicated configuration (http://forums.ni.com/t5/Instrument-Control-GPIB-Serial/Split-second-lag-when-controlling-two-instrum... and was advised to try the producer consumer Architecture.) I found the documentation on the website (http://www.ni.com/white-paper/3023/en/, https://decibel.ni.com/content/docs/DOC-2431), searched the forums and built my own VI. While my first attempt at a producer consumer Architecture has solved some of the problems I had when I posted on the subject, however, new questions have been raised regarding the reading and adoption of the VI.

  I am currently able to run the VI and update the settings on the device. Previously, I'd get a freeze while the instrument has been updated and could not switch settings until it was done. This has been resolved, although that reading updates only when a parameter has been updated, although it is outside the structure of the event. In addition, the Stop button does not in any context. I also got occasional mistakes on the part of Deqeue, but the major part of the sentence is error-200279 'A tried to read samples that are no longer available' to DAQmx Read. I realize that there is a problem in my loop of producer but have not been able to find a way to solve it.

  This is my first attempt at a producer consumer Architecture and already I can see that it is a powerful tool. I read as much as I could and looked at examples, but should have some problems at the beginning. Would be very grateful of any advice so I can take full advantage of the architecture.

  Hope to hear from you,

  Yusif Nurizade

  You're going to overflow this buffer, unless the events are generated faster than "sample rate/number of samples.   Period.  Nothing could be simpler.

  You don't need a local to stop your curls.

  Try something like this attachment.  I simply moved the structure of the event in its own loop dedicated since it had nothing to do with acquiring data at all.

  Data acquisition loop stops very well when you destroy the task and destrying the stops of power queue (sending the default values of the queue for the power control) for EXAMPLE, to ADD a group of setting 'Safe shutdown' to a 'package' and it wire to the Center terminal (Prototype).

• Producer/consumer or master/slave, acquisition, control, analysis and recording of data

  Hi all

  I have NEITHER cDaq-9188 and its modules NI 9214 (thermocouple), NI 9203 (HAVE current) and NI 9263 (AO tension). I need to measure the temperature and pressure, and according to these data, I need a frequency converter to drive a compressor control. I've developed acquisition, analysis and recording program by the use of the state machine, the design of producer/consumer model and I have no doubt about their. They all work very well. Now, I need to add a control program in their. The problem is that I need to check the compressor with feedback from temperature data permanently, but I do not necessarily all the data acquired and permanently from the results of the analyses. For example, I need to record data once in 30 seconds. Which model desing should I use for this task?

  Edit: I was not able to find examples of advanced program relevant to the design of master-slave model. If you know where to find them, could you write in this thread please?

  The declarant buffer not data.  Do only the queues.  A new notification replaces the old value if she is ever read or not.  You would be loss of data with the notifiers if the loop of consumers with a notification utility cannot keep up with the data that they fade.

  What I show all the data buffers through the queue in the loop of the producer.  The queue of the consumer removes all data and do stuff with him (such as logging) if the elapsed time is over.  What is the problem with that? That is what for (imstuck) described in his message.

  The other alternative is that you put the timer into the loop of the producer.  Have the Boolean value TimehasElapsed drive a deal structure this place only the data if the time is over.  In this case, only some data gets queued, and consumer loop removes all data as it gets and it opens a session.

• overflow memory for the producer consumer

  I'm trying to save data from 4 ports to 40.96 Mhz. using a producer consumer architecture and a PCIe NI 6527 B using an external clock.

  I inherited code which works for 2 ports.  I tried to add additional ports and changed the size of the data to the DAQ.mx queue and data.  Launch the program several times, reach conflicting error messages after less than 2 seconds from the beginning:

  Error 200284: Some or all of the requested samples are not yet acquired.  [...] To make available samples more quickly, increase your sampling rate

  200361 error: Overflow memory device on board.  Due to the limitations of system and/or the bandwidth of the bus, the driver could not read the device fast enough to follow the flow of the unit.  Reduce your sampling rate.

  What is a race condition between the error messages, a problem of timing of start or something else?

  I approach, how to debug these types of problems?  How can I determine what is causing the error?  I can't single step through because I'm at the wheel of sampling with an external clock.

  Running on labview 2012 Windows XP on the machine who's 3.17 GB of ram.

  Try to reduce the size of your buffer.  In fact, simply leave the calendar DAQmx unwired.  The size of the buffer must be large enough by default.  And then also try to read less data at a time, as data instead of data 500ms 10ms.  What I suspect here, it's that the DAQmx buffer is too large and therefore must use the hard drive for part of the buffer, to slow things down a lot.

  Other notes here:

  1. do not use the time-out to stop your loop of consumer.  Your producer should send an order of a certain type to your consumption by telling it to stop.  In this case, I would use an empty array.  And then, you must release the queue after the loop of the consumer.

  2. you want a constant FALSE to Append Array/String input size of the binary file write.  This will remove the 2 I32s at the beginning of each table that you write.  Eelle are here to tell the size of the table being written.  But since you are just data flow, I doubt that you care about those.

  3. instead of the entire setup of producer/consumer, have you considered using just the DAQmx Configure Logging VI do DAQmx stream directly to a TDMS file for you?  Makes things much faster and much easier on you.

• Total number of samples per channel

  Hello

  I was wondering if you can call a function that returns the total number of samples per channel read. I try to get a precise timestamp.

  I use DAQmx ANSI C developer environment.

  According to NOR:

  Option #1:

  Try and do exactly what the driver is doing.  This will require you to do exactly what you do in the displayed example.  Call time current system immediately before calling the DAQmx Read and subtract dt * x where x is the number of samples already acquired.  It will take you to know exactly how many samples were acquired.  It can be found by calling the Total property of the samples by chain acquired immediately before the DAQmx Read.  This is to introduce some points for innaccuracy.  For example, you're time system is already innaccurate to a certain amount.  In addition, it takes some time between the system times call, calling the total number of samples acquired and calling the DAQmx reading.  If 2 samples are acquired between the call to the time system and the total number of samples acquired, you could be shifted a few samples.  For the slower clock rates, you will have more precision.

  I try to attempet to program this solution, but cannot find the total number of samples per channel acquired property. If anyone can help me, your help will be very appreciated.

  Thank you for your help,

  Vladimir

  Hi Vladimir,.

  Here is the property you are looking for (as the C reference help):

  

  You will be able to get accurate relative timestamps, since we know that our acquisition is based on a sample with a certain dt clock.  The value of initial time must still come from the OS.

  Best regards

  John

• Programmatically change the number of producers in an architecture of producer/consumer

  Hi all

  I've got 3 momo SoMat I am streaming of data to 10 Hz. I plan on 3 producer loops and loop a consumer to treat.

  I am pretty sure when I show my customer that they want to increase the number of devices. This scuppers then the producer/consumer model unless I change by programming the number of producers and the rest of the architecture associated.

  Is there a way to do this or a better architecture?

  Phil

  As long as there is an ID any in your command of the queue, I do not see why your consumer cannot handle the producers as much as you need.  I would turn the producer code in a Subvi.  Make sure reentrant Subvi.  Then, you can call dynamically that VI as many times as you need, one for each instrument.

• measure and order through producer/consumer

  Hello people,

  IAM trying to conduct a projekt automated, to test an actuator.

  It must measure signals, process them and also has to create the actuator control signals.

  So far no problem... But it must also operate 3 ditch or several rounds of tests that each has different ControlSignals.

  (example: Test1 - enter: 40VSin (40 Hz), Test2 - entry: Triangle, Test 3 - input: 100Vsin (100 Hz))

  It seems always not difficult enough, but as a beginner of LabView, I m having a lot of trouble to find the right Structure to achieve all this. normally I use SPS systems, but this time to Labview

  Had a few trys a hav downloaded to them.

  But the Structure of producer/consumer makes problems. It does not give all the ProducerLoop signals. :/

  Is there a way to outher Labview programming more effective on this problem?

  4 I'm sorry the bad English

  Greetings

  State machine...

  

• acquisition and recording of analog data with producer consumer model

  Someone on this forum, in a separate last week discussion, suggested that I use the producer model consumer data acq.  My ultimate goal is to acquire analog channels 1-4 continuous data, display graphical band style and save the data on the boot disk when the user presses the 'Start Saving' button (and will continue to display recorder cards).  Economy will stop when the user presses the button "Stop Saving" but strip map will continue to operate.

  My attempt to use the producer-consumer model is attached (LV 8.5 only).  It does not work.  I have not tried to implement for recording user controls - just trying to make simple continuous display and save (1 channel) at this stage, using this model.  VI runs, but the graphic Strip is never updated with the actual data, and the data file that is saved has zero byte inside.

  Thank you.

  WCR,

  Looked at your code, and you are right.  It won't work.

  Take a look at this example:

  http://decibel.NI.com/content/docs/doc-2431

  The VI of the acquisition must be inserted in the loop of the producer.  In addition, you must tell him how many samples for (otherwise, it will get 0).

• Producer-consumer mode, PDM and Acquisition journal continues

  I created a VI based on events to control the parameters of data acquisition. I created a queue of producer-consumer in TDMS file in the loop of the consumer.

  Question 1: Why should I get DAQmx TASK through each defined event? If I don't, I get error task DAQmx.

  Question 2: I need the QUEUE of each event? If I don't I get error in the file close TDMS (consumer loop)

  Question 3: When I look at the data file, I get manily in the near TDMS file loop of consumer-related. Since there is no element in the QUEUE why should - I get this error.

  Please advice.

  Thank you

  This is certainly not how I would like to start to create a Soft Front Panel for a task to HAVE.  Leave to file logging asside for now (appearing, it is actually very easy to add later.)

  As food for thought - and because that create a FPS really involves a slightly different thought where you started I whip a 'start' of a FPS.  It also shows how to create a simple API around a 'resource Module.   (Just a natural extension of a "motor action - if you haven read the nugget of community is always a good read.") http://forums.ni.com/t5/LabVIEW/Community-Nugget-4-08-2007-Action-Engines/m-p/503801)

  What I compressed is not complete - but you should get an idea of what to expand and where.  You could even have there more faster here than when you are now.

  An approach like that can really help when you go to unwind the problems as you mentioned in your code when you are unable to move around the information that the GUI can't really do use anyway and not IS NOT NECESSARY at this level.  the guys from 'Computer Science' will use terms such as 'Hide data', "Functional Abstraction" and "Encapsulation".

  The capture below is meant to tease the project so that others can get the idea of code - (sorry no LAVA TDC today! )

  

• I want to buy an iBook. There are 2 different books with the same name, author, and the book cover. They are different number of pages with different prices. Specifically, all the light that we do not see. " How do you know that we purchase?

  I want to buy an iBook. There are 2 different books with the same name, author, and the book cover. They are different number of pages with different prices. Specifically, all the light that we do not see. " How do you know that we purchase?

  I would get one that has 4700 comments already.

• EqualLogic GroupManager displays a different number of replicas, 2 outgoing and incoming 1.

  GroupManager displays a different number of replicas, 2 outgoing and incoming 1.  Is this a normal behavior?

  

  I raise this question to technical assistance from Dell.  They checked with their lab environment and confirmed the same behavior.  There is no functional cause whose status is displayed like this.  Two points, they said:

  (1) the number of the line leaving includes the history of replication.   It will show you an extra line in addition to the number configured in the replica set. (in my case, it's 1 (configured) + 1 (extra), so 2 total)

  (2) the number of the replica by entering the real number of replica set used for the function of data redundancy.

• producer-consumer: optimize data acquisition rates

  I have a type of producer-consumer of application in which a single loop continuous waiting there and reads data from the card and another loop readings/backups of data. But besides a loop more trace data. The number of channels and real-time scanning is set by the user, the time it would take to save, view, and analyze each data block (an iteration of analog-to-digital reading) may vary according to different parameters.

  I'm putting 'number of samples to get' big enough on analog/digital playback to the beginning so I don't get the overflow of queue. Now I would like to adjust automatically when the program is running so I understand any overflow from the queue and at the same time the data are not exposed in the huge chunks at a time. Someone did he do this kind of thing before? For now, the only idea I have is to read the number of items in the queue at all times and use a mathematical formula to increase or decrease the number of samples.

  Abdel2,

  The number of items in the queue of streaming and using a mathematical formula to increase or decrease the number of samples is a good method. You can also use the decimate 1 D table function to display a smaller grouping your data if your problem is that you do not want to display huge chunks of data at the time.

  

• Producer / consumer set loop of dynamic data item type

  Hey all,.

  I do a simple exercise of producer / consumer in a loop. In my loop of producer I audio Aqcuerir and in the loop of consumer I'm projecting on a chart

  Everything works as I had in mind, the only thing that bothers me is the way that I had to set the type of the element to the block "Get the tail" at the beginning.

  I knew no better way to get the kind of data that I used to just take an another "acquire its" Express VI and which hang. But that may not be the only way to get there, right?

  Note: I know that I might not need to use a producer / consumer design tend to do, but I need to get hold of technology for school work so I came with this exercise just to get a hang of it.

  Thanks in advance,

  Al.

  Al,

  You just need to feed the correct data type in this entry, which you did by getting the output of a second acquire its Express VI.

  You can also use the "Convert to Dynamic Data" function to do this.  When you drop to the bottom of the function, you will be asked to give the input type.  Tests I've done, it seems not to matter, but for example if you chose the entry to a single scalar type, you need to feed a digital constant (change to double type) in the entrance and use the output of dynamic data such as line item data.

  I don't like the dynamic data type because it is not very clear as to what it is.  Another thing you could do would be to use the "Convert from Dynamic Data" function to change the output of the VI of its acquisition to a different data type for more or less to avoid the original problem all together.

• export to spreadsheet - data 2 channels appear in alternation with loop of producer/consumer

  Hello

  I'm having trouble with the function "Export the waveform to the worksheet" - but it is not clear to me if the problem is with how I use the export feature or if I am wrong concatenating two waveforms of different modules of the series prior to export, or if my queue is wired incorrectly for producer-consumer loops.

  I use a hunts SMU-1073 with SMU-6361 and 4330 modules (tension and strain). I tried to change the example of the "entry analog cross synch" for use with a structure of producer-consumer (see VI below).

  The output of the worksheet contains a large part of the data in the string tension, followed by a smaller piece of data (with timestamp) strain, after which the alternate output data between data of tension and strain.

  Can anyone suggest where I could go wrong, or how I could solve this?

  Attachments do not work, so I'll try to post in an empty message directly after this post.

  Thank you

  Claire.

  That's what I thought.

  A number of wire.  -1 gives all the samples available in the buffer (which can be zero for some reason any).  A number will expect that there are many examples.  If the two readings can wait until they have both the amount of data requested.  This way, they will also have the same number of samples and be better aligned in the text file.

  Your loop will continue to run until you press stop or get an error.