Similar Questions

• Analog inputs measures with NI6229 using the DAQmx driver

  Hello

  I have four different analog inputs connected to ai0 to HW 6220 ai3. I read these values with a single task, all 4 channels assigned to this task. When ai0 reads 7V, I see 0.8 V ai1 too, but I expect to be measured 0V. If I just assign ai1 to the task and measure all 4 channels, then I measured 0V as expected (although ai1 contains 7V, I just don't measure it).

  Another comment 'funny', is that if I change the order in which I add channels to the task, measurement errors are different.

  However, when measured with a multimeter 4-channel show tensions as expected.

  Given that my calling task is can not block, I call the function

  DAQmxReadAnalogF64 with timeout = 0 and numSampsPerChan = 1.

  Any help is appreciated.

  Thank you

  Kind regards

  Deepa

  Deepa,

  Thanks for the code snippet.

  When you call DAQmxReadAnalogF64 the first time and you set a value of timeout of 0, there is a chance that the acquisition is not yet initialized. This is the expected behavior and should not be a problem. If the timeout error died at the first call, you might ignore it or set a different expiration time for the first call only. In all cases, you should drop the first value and start with the second value.

  Jochen

• DAQmx and SCXI-1160 with 'DAQmx switch Open Relays.vi '.

  Hello

  I use DAQmx to pass the baton on a map of SPDT 16 SCXI-1160. When I run the 'DAQmx switch Open Relays.vi' with the entry "ch0/SC1Mod1 / ' I think the relay normally open position 'NO '. But this is not the case, the relay is in the position of the NC. Here are the steps I do a simple VI.

  1. define the topology of the 'SC1Mod1' to '16/1160-inverter.

  2. call the 'DAQmx switch Open Relays.vi' with the string "/ SC1Mod1/ch0.

  3. then I take a physical measurement, with a multimeter on the SCXI-1324 terminal block and the relay is in position "NC".

  4. If I run the "DAQmx get relay switch Position" he's back "Open"!

  Is this the good behavior, and if so can someone explain the logic behind it.

  Thanks in advance,

  Michel

  Hey Michael,

  Sorry, I didn't know that you were actually able to control the relay and you receive just the reverse logic. To answer your question, on the SCXI-1160 module, there are three connections for each channel: COM, NO pine and pine of NC code. Reset, COM is connected to the spindle of the NC. When you issue a command to OPEN channel 0, COM will stay connected to the NC pin, even if the software indicates now that the PIN is open. When you issue a command NARROW-gauge 0, COM will be now connected to pin number and not on the spindle of the NC.

  A better way to think of it, is to focus only on the relationship between COM and no. pine. When you send a BLANKET order, this connection between COM and no. will be open. When you send a CLOSE command, the connection between COM and no. will be closed. Consult this manual for a visualization of how this switch is set up: http://www.ni.com/pdf/manuals/320513b.pdf. Refer to page 2-9 and 2-14 of this manual for pinout.

  -Nathan H

• Frequency of measurement with cDAQ NI 9402 chopper

  Hello world

  I'm new in the world of the cDAQ and try now just get a frequency of a TTL signal output chopper.  I confirmed 23 Hz frequency on an oscilloscope.  It's a nice clean 5V square wave, but when I try to measure the frequency in labview using a VI (dig frequency of continuous measurement) example, it comes to expire.  Trying to look at the entrance of the signal in express shows signal an incompatible digital signal that is around 3 Hz and clearly the result of the port being interviewed for entry too rarely.  The final objective is to get this work with the labview vi PLL is a detector lock in the amplifier, but first of all, I have to be able to measure and to read correctly this frequency.

  My hardware is a cDAQ-9174 with a 9402 OR for use with the digital input.  I don't know it's important, but the 9402 module is in slot 3 and I'm on channel 0.  The software is labview 8.2 with DAQmx 9.1.  Is there some timing issue material or the definition of I'm missing here?  Any help is greatly appreciated, thank you!

  Hi Skaboss,

  Counters have multiple terminals (source, the door in and out), which map to separate on your NI 9402 PFI lines. For the measurement of the frequency, the default input terminal depends on the method of measurement (low frequency, high frequency, wide range). Here's the relevant section of the NOR-DAQmx help (which is on the Start Menu):

  Connections of signals C series for counters

  The following table lists the default input for various measures of meter terminals. You can use a different line of the PFI for one of the input terminals. To edit the entry PFI for a measurement, use channel NOR-DAQmx attributes/properties.

  NEITHER 9402 and NI 9435 (4 channels)

  Measure	Ctr0	Ctr1	Ctr2	Ctr3
  Number of edges	Edges: PFI 0 County Executive: PFI 2	Edges: PFI 3 Branch Count: PFI 1	Edges: PFI 1 Branch Count: PFI 0	Edges: PFI 2 County Executive: PFI 3
  Pulse width measurement	PFI 1	PFI 2	PFI 3	PFI 0
  Duration/frequency measurement (low frequencies with a meter)	PFI 1	PFI 2	PFI 3	PFI 0
  Measure of duration/frequency (frequency with two counters)	PFI 0	PFI 3	PFI 1	PFI 2
  Duration/frequency measurement (wide range with two counters)	PFI 0	PFI 3	PFI 1	PFI 2
  Measure semiperiod	PFI 1	PFI 2	PFI 3	PFI 0
  Measurement of two-Edge separation	Departure: PFI 2 Stop: PFI 1	Departure: PFI 1 Stop: PFI 2	Departure: PFI 0 Stop: PFI 3	Departure: PFI 3 Stop: PFI 0
  Measure of position	A: PFI 0 B: PFI 2 Z: PFI 1	A: PFI 3 B: PFI 1 Z: PFI 2	A: PFI 1 B: PFI 0 Z: PFI 3	A: PFI 2 B: PFI 3 Z: PFI 0

  Alternatively, you can override the default with the CI. Freq.Term channel property.

  Brad

• Multitask with daqmx

  Hello

  I am currently working on a Senior design project where I have to measure rpm, torque, pressure and temperature.  I use strain gauges, pressure sensor and a Hall effect sensor, thermocouples for these readings.  A myDAQ collects readings rpm and pressure while a cDAQ collects couple and readings of the temperature with NI 9211 and NI 9237 modules.  I have created LabVIEW screws for each sensor and they work.  The problem I have is when I try to create a VI with DAQmx who reads all the values of these sensors simultaneously.  The VI I joined randomly displays one of the measures while other measures remain empty.  How can I change my VI so I can show all my readings at the same time?

  Yes.  Create multiple tasks, where all the strings that are common to a specific device are grouped in the same task.  Then go and run these tasks in parallel.  Do you need a precise synchronization between the tracks in the different devices?  If this isn't the case, then the method should work perfectly.  If you need a precise timing, things would get more complicated, but might not be impossible.

• Timing embedded with Daqmx on PCI-6132

  Hello

  My colleague and I are trying to make a program Labview which starts a timer when the first trigger (sensor) is struck and stop the timer when the second trigger (sensor) is reached in 2012. We currently have a program for her, but this program was not sufficiently precise. Also the current program is using the DAQ assistant, but we would like to replace with daqmx triggering. We have also tried to use the OnboardClock on the PCI-6132, but still could not do the work programme.

  Is there anyone who knows how to do this and could explain it?

  (In the attachment is the current program)

  Thanks in advance,

  Tommy van Geest

  Hello Tommy.

  You can share your current code?

• With a sampling of the data with DAQMX, error-200279 occurs when making 2d array dbl

  Hello

  I did a system of simple analog voltage with DAQMX data acquisition.

  It is made for reading of capacitance, where output capacitance value out of a circuit in the periodic voltage signal.

  What I want is to get data from four capacitors simultaneously through four channels, using samples n n (dbl 2d).

  The structure of my VI is almost similar with examples of continuous sampling of voltage in LabView, with the exception of a few other calculations in the loop.

  And for the synchronization of the trigger, I've corrected the edge of release with the external signal from the capacitance reading circuit.

  Version no. 1 has a channel for data input voltage. Version n ° 2 has four channels for the input data.

  While ver.1 can get accurate reading of four capacitors circuit data each (a single channel at a time),.

  ver.2 acquires four channels of data, with a single thin data channel, all the others were wrong.

  I saw a 200279 error occur in the DAQMX read part 2d dbl, so I tried increasing the buffers by changing the sampling frequency or the number of samples, but it wasn't everything.

  I rose for most of the forums with the 200279 error, but the solution would not work on mine.

  Anyone can find the problem? I will attach my screws it may include a bit of Korean language, but most of them are in English, shouldn't be too hard to recognize. Sorry for the inconvenience.

  Oh I forgot, my DAQ is NI USB-6259, and it works in Win XP sp3 and LabView 8.6.

  Thank you.

  Hello Azurenight,

  The 6259 is a DAQ card of the M Series Multiplexed, which means that it is not possible to sample each signal at the same instant, rather the channels are all sent through the ADC even and must be sampled in order. More information on this can be found here:

  LabVIEW Help: Multiplexing compared with simultaneous sampling

  http://zone.NI.com/reference/en-XX/help/370466W-01/mxcncpts/multisimulsamp/

  It may still be possible to get the data you need with the card you have - could you give more information about the maximum eligible period between samples on different channels?

  If you require * real * simultaneous sampling, you will probably need different hardware.

  Kind regards

• Is it time stamp with daqmx read

  Hi all

  Simple question.  I have currently not creating a task or starting a task, I simply create a channel and reading that chanel.

  It is...  Why I don't get a timestamp when you do and do I create a task to get one of this?

  There is a timestamp when you use the DAQ Assistant or when you choose to return a data type of waveform with DAQmx Read.

  You can't do a reading without a blemish. You don't have to create the task in MAX, however.

• time of release with daqmx

  Hello

  How can I set the time of liberation with DAQmx?

  In general, with a single DAQ hardware, the two signals are connected at the same time and the acquisition time is a function of the sampling frequency and number of samples read. For example, with a sampling rate of 1000 samples/s and 50 samples, the acquisition will be 50 msec. You then get a returned array if you wanted to watch a single signal by iteration of the while loop, it is simply a matter of indexing the specific channel to the table. You must set the mode of continuous sampling to avoid gaps and precise timing. Using two separate tasks and switching back and forth would add a lot of overhead to close/create tasks and you have little control over this period.

• 2009 with DAQmx Installer

  We distributed an integrated application that uses DAQmx 8.x and LabVIEW 8.6 for several years.  I'll call the application MyApp 2.8.  We are working on a new version that uses LV 2009 and DAQmx 9.x, which we will call 3.5 MyApp.  When build us and deploy a Setup program for MyApp 3.5, then try to use it on a computer that already has 2.8 installed MyApp, the installer complains about dependencies and said that the two DAQmx 8.x and MyApp 2.8 must be uninstalled first.  I spoke NOR cela briefly and told me that DAQmx 9 was a pretty radical overhaul that required this change.

  It's annoying and slow for us, but almost untenable for our customers.  First of all, MyApp MyApp 3.5 and 2.8 are compatible, and we prefer to leave MyApp 2.8 installed as a backup as people get used to 3.5.  If the customer needs:
  Uninstall MyApp 2.8

  Uninstall DAQmx 8.9

  Install MyApp 3.5 with DAQmx 9.0

  Reinstall 2.8 MyApp (as if they can still find the disc!)

  Far too many steps and complications.  In addition, it is not really necessary.  If the runtime for 2009 is already installed on the computer (for some reason any), you can simply copy the MyApp 3.5 on the computer and it will run with DAQmx 8.9.  But this only postpones the problem, because at some point the customer will upgrade once again, and we will have forgotten that they were installed with a workaround, and...

  The really frustrating part is setup for MyApp 3.5 refuses to install until MyApp 2.8 is uninstalled.   While we have proven that MyApp 2.8 will work very well with DAQmx 9.0.

  Is anyone else noticing this problem?  Has anyone found any better workaround?  Is the same problem when we jumped 2009 and returned with 2010 and the last DAQmx?

  Thank you

  DaveT

  DaveT,

  You're right - for this aspect of the problem - my proposed solution won't help. At the price of a larger Setup program, including the full version of DAQmx probably will give the upgrade experience you want. If the web download size is a concern, perhaps you could provide two builds of your product - with the acquisition of complete data (for those of you who have your old product) and with smaller data acquisition (for those who do a clean install)?

  In addition, certain registry keys to remove the dependency I guess hacking is sort of an option, but it probably isn't the type of solution you are looking for. (We are currently researching the addition of some extra features in the uninstall program OR allow without taking account of certain dependencies, but nothing is currently available).

  Kind regards

  -WesW

• Measures with the date Conference

  Hello

  I have to make an application, as part of my end of study project, which allows to calculate heat flow. Pour this, I have data measured with thermocouples. These data are stored on a data recorder that record these data on a .txt, .xls or .csv file (it is to be chosen by user).

  I'm not very chiseled with LabVIEW.

  In a Prime Minister, I tried to read the .txt file data. I can read the 1st line as I wish but not others.

  So I decided to work with a .xls file. The temperatures Conference goes smoothly. For time is the date, it's more complicated. Indeed, I would like to USE date and time corresponding to each measure to plot a graph XY with the date and time X and Y the temperature of the thermocouple.

  Kind regards

  Here's an example (VI from LV2011 but attached VI en LV2010) made on the basis of your code. Comment by watch it extract the news date and time of the string and generate the the from graph XY time in seconds in X. realized very quickly, it is without doubt room for improvement but you will serve as a basis for work at least.

  

  To define 'Structure box' serving at first as far as being 0 and calculate relative time to the following samples. Thus the x-axis of the graph starts at 0.

  My time is short, I renounce other comments but I happy to answer specific questions.

• HorizontalFieldManager Fix width automatic measurement with height

  Hi all

  I would like to make a HorizontalFieldManager with a fixed width, but automatic measurement with height. Do anyone with a good idea about it. Thanks for the help!

  Thanks for your help!

  Although your idea is a solution is not complete, it gives me a good idea to solve the problem.
  My solution is to change my coding over a part of the first horizontalfieldmanger:

  HorizontalFieldManager hfm1 = new HorizontalFieldManager()

  {

  public int getPreferredWidth()

  {

  Returns the value 100;

  }

  protected void sublayout (int maxWidth, maxHeight int) {}

  Super.sublayout (getPreferredWidth(), maxHeight);

  LeftField RadioButtonField = getLeftButton();

  If (leftField! = null & is equal to (leftField.getManager ())) {}

  int x = 0;

  int y = 0;

  setPositionChild (leftField, x, y);

  }

  }

  };

• VB6 with DAQmx compatibility with Microsoft Vista and Win7?

  Hello

  I'm trying to figure out how what are my options for running my VB6 applications that use the API C of NOR-DAQmx with Vista or Win7.

  I have certain applications that we have maintained in VB6 (with Measurement Studio 6).  I programmed the software for traditional OR-DAQ hardware originally.  I suppose that I used for about 10 years or more.  About 2 years ago or if we needed to use our software with hardware recent DaqMX I've been able to use the API C OR-DAQmx for Visual Basic 6.0.  My application really support two hardware platforms simultaneously.  The person responsible for the project wanted to have 1 single application managed the two platforms (daqmx and inheritance).  So far, it's all great.

  If anyone knows what are my options if I want to use Windows Vista or Windows 7.  We are currently running this app on Windows XP.  I'm ready to upgrade my software if necessary although I have to spend to VB.net and Measurement Studio 7.1 (I currently have).  But if we were to happen tomorrow is there any compatilibility. I read that the traditional / legacy NOR-DAQ is not supported in Vista (Win7).  I googled and found there was a beta version which seemed to weakly in support of the legacy but did not support USB devices which is what I have (6020e (inheritance), SCXI (daqmx), 6259 (daqmx).)  I've heard that Windows 7 will have a virtualization system for XP applications that do not work natively under Win7, but for some reason, I doubt that the drivers and hardware will be run this way.

  Also, should there be differences between Vista and 7? I'm an XP user and computers I support many XP so I really have no experience with Vista.  I plan to install the Windows 7 RC to try some of this stuff.

  Thank you, David

  Use of our released traditional DAQ drivers is not supported on Vista systems, even running in virtual Windows XP mode. The driver works at a lower level which can emulate a virtual mode.

  However, we have a public beta version for a traditional DAQ driver that works for Vista. You can read about this version beta here

  -Abram

• Impossible to get more than 1 channel to read with DAQmx cDAQ-9172 under Windows 7

  I have the cell load, voltage, and input thermocouple connected to a cDAQ-9172. My sensors entries have been scaled and verified in MAX, and all of them work.  DASYLab 13, the driver is "dcDASY.dll" and the hardware configuration is "NI MAX.

  When I add a task NEITHER-DAQmx Analog Input (that is, a set of scales) it appears correctly. If I add a second channel of the task and select it, I get this message:
  'Channel of task name saved with the module is not available. DASYLab resets the module parameters for usable first channel name task. »
  The name of the task remains the same for each new channel I have Add. If I change the name of the task by using the tab to the drop down menu, it says:
  "You have configured several ways out for the module. If you modify the task, you lose the settings. You want to change the task? »
  Both display the same data channels, and I can't work simultaneously several channels. It seems I missed something obvious, but I can't.

  The parameters are:

  Measurement and Automation Explorer 4.6.1
  NOR-DAQmx 9.0

  Material:-cDAQ-9172
  Slot 1 - NOR 9215 (0-10 Vdc analog voltage)
  Slot 2 - NEITHER 9211 (thermocouple)
  slot 3 - NI 9481 (relay)
  slot 4 - NI 9237 (entry deck w / excitement)
  housing 5 - OR 9402 (DIO)
  slot 6 - NI 9263 (0-10 Vdc output analog)

  Thank you

  You can't perform different tasks (continuous) HERE on a single chassis. The first tasks that starts will be 'the resource booking '.

  Combine the AIs of the various modules in a single task (see photo): start by creating the task of thermocouple. Then add AIs 9237 (e.g. Kraft) and 9215 (volts) using the button with the blue, symbol. Set the mode of synchronization of the task of "continue". Save the task, start DASYLab (second photo).

  Change a task (adding channels, etc.) to the MAX while DASYLab works always, will result in unexpected behavior. To synchronize the configuration of MAX with DASYLab, you will need to close/restart DASYLab or use the 'sync' of the function (see photo 3 "syncmax.jpg"). You can set this function as a shortcut by right-clicking on one of the eight green or grey circle things.

  You should think about an update of the MAX/DAqmx drivers. 9.x is a little outdated.

  Updated at least DAQmx 9.9, better 14.x or 15. 0 (stay far 15 1.x).

• Problem with DAQmx Schedule VI (sample clock)

  Hello to you all,.

  I'm new to this forum, please bare with me. I have some experience with LV, but I am relatively new to data acquisition projects. I use LV2009.

  I want to make sure that I use the hardware timing (instead of software distribution) in my project so I followed some of the threads here as sugested to use DAQmx Schedule VI. The problem is that no matter how I set the system I get the same error-200300 invalid calendar
  type.

  The project is simple. I encode with 1000 pulses per
  Rev and it is mounted on a shaft of a turbine water goes thru. I'm watching the frequency
  and so the rotation of the shaft which tells me that the amount of water flows through the turbine. In the end, there will be 2 channels
  by every encoder and ~ 3 encoders (turbines) total and calibrated the main meter that will give me constant impulses and all encoders will be compared to this master frequency.

  I'll use PCI6602 DAQ, but
  now, for the development, I use USB6221. Let's say that the
  frequency is between 500 Hz and 10 kHz. What I am doing wrong? Or maybe better to ask - what would be the right approach for this project?

  Thank you

  Marty

  Hi Marty,

  It seems that your question is already answered here, but Jason is correct that the 6221 neither the 6602 support a clock sampling for frequency measurements.

  As Jason mentioned, your best bet is also likely set the mode of synchronization for "implied". This means that the frequency value is sampled at the end of each period of your input signal. In addition, a solution that is clocked by the software (On-Demand) might be acceptable.

  X Series DAQ devices allow an external sample clock to use for frequency measures (described in the Manual of X series). Frequency of sample-clocked measures are useful in very specific
  circumstances, but it does not seem that you need this feature based on what you've described so far.

  (621 x) bus-powered M series can also be configured to use an external sample as the X series clock but do you not have the same features described in the manual of the X series.

  I hope this helps!

  -John