Analog output using DAQmx task

Similar Questions

• How can I pause and resume the analog output using DAQmx?

  I use a DAQ hardware to produce an analog waveform.  I would like simply to break the output of the wave and then resume where it left off.  I use DAQmx and LabVIEW 2011.

  I've seen examples that use a digital or analog break trigger, but I would take a break in the software only.  How can I do this?

  -Joe

  Hi Joe!

  I spent some time thinking about it and I realized that you can technically use a fundamental mission of the analog output, as you previously wrote that runs continuously. However, the generated output samples are controlled by the sample clock pulses, and can be manipulated to fit our needs "suspension."

  To do this, we will need another counter task that generates a pulse train (see our examples of shipping under material input and output > DAQmx > generating digital pulses > generate dig Pulse Train - Continuous.vi) that stops and starts the user to choose. This can be in another quite VI or controlled by software. We will use this as the task of our output sample clock.

  Then, the task of the AO, wire a constant to the sample clock source and select ' DevX/CtrXInternalOutput"based on the counter that you specified in the task of counter. You will need to choose "I/o name of filtration" and check the box that says "include advanced terminals' and right-click of the constant. See picture attached as a reference. In this way, the task of the AO is constantly running, but it generates only actually all data when the meter running task.

  

  Let me know if you have any questions!

  Have a great day!

• Frequency measurement of analog input using DAQmx C APIs on SMU-6341 map

  Hello

  I use Linux DAQmx and attempt to measure the frequency of analog input using the map DAQ SMU-6341.

  There is an ANSI-C frequency measurement example:

  / usr/local/natinst/nidaqmx/examples/ansi_c/Analog_In/Measure_Frequency/Cont_Freq-Int_Clk-SCXI1126

  However, the call to DAQmxCreateAIFreqVoltageChan results in the following error:

  DAQmx error: selected physical channel does not support the type of measure required by the virtual channel you create.

  Create a channel to a type of measure that is supported by the physical channel, or select a physical channel that supports the type of measure.
  Property: DAQmx_AI_MeasType
  Required value: DAQmx_Val_Freq_Voltage
  Possible values: DAQmx_Val_Current, DAQmx_Val_Resistance, DAQmx_Val_Strain_Gage, DAQmx_Val_Temp_BuiltInSensor, DAQmx_Val_Temp_RTD, DAQmx_Val_Temp_Thrmstr, DAQmx_Val_Temp_TC, DAQmx_Val_Voltage, DAQmx_Val_Voltage_CustomWithExcitation

  Task name: _unnamedTask<0>

  State code:-200431

  DAQmx does support the function of the frequency on the map 6341, or should we use examples of voltage and calculate the frequency manually?

  Frequency of HAVE it is a type of channel that has been supported only on the SCXI module name of the example.

  You will need to use a voltage input channel and calculate the frequency manually for your device.

• Analog output using waveform Timing stops in brief

  This is a pretty abstract to describe problem, so I'll try my best.

  I give myself two entrances, a low and a high. Here are the tensions. I create a signal which will be the ramp from low to high and from high to low, forming a pyramid. The signal that I create is perfect. The dt signal.001 because I'm out there at 1000 Hz in an analog channel. I left it to an analog of the ExpressVI using "Waveform Timing" (the little box with a timer on this issue when the information of sampling). The problem is when I change the number of samples with this signal. It seems if I increase the examples of this signal (dt-keeping and frequency of output, thus increasing the LENGTH of the signal), the Express Vi that emits the singal stops and does not address the rest of the signal.

  I can't rip off code to post here because it is not my property. I hope someone has an experience with this and can explain how an Express VI would cease treatment of an intermediate signal of the signal.

  Thank you

  I have corrected this problem.

  If you are using an express VI, the FIRST time you call this VI, all timing information you pass, the VI will be remembered forever and he will never change. I had to replace by the low level screw and stop/clear the task in order to erase this memory.

• Synchronize the analog continuous entry and continuous analog output using the unique PCI6024E data acquisition card

  Hello

  I want to generate the continuous signal and at the same time I want to read that signal that I generate using a single card DAQ. I want to generate signal and the received signal is synchronized and in phase.

  I looked at several samples on the sync, but it quiet confusing. One using the same clock of entry while the other use a trigger to start. I use the PCI-6024E DAQ card.

  Can someone help me in this regard?

  In two of these screenshots, the task to HAVE started first (that's what you want, because it is the task of the slave).

  Typically for AO, you can simply write a unique period of your waveform, and then regenerate again and again.  Your waveform would be preset before the task starts.  If you need to update the waveform on the fly according to enter programming during execution of the task, you would disable the regeneration.  In addition, if the wave form is such that it cannot be easily represented by a predefined buffer (for example, it is a strange frequency which is not a same ditch at the bottom of the sample clock), then non-regeneration is the way to go.

  Best regards

• Generation of two channel analog output using NI USB-6221

  
  

  Full question

• Trigger start analogue does not work for the tasks of the analog output

  Hello. I wonder - what someone has tested the trigger mode analog start for continuous output voltage-. example of VI under hardware input and output - analog output folder in the Labview.

  My camera's SMU-6358, who has two lines APFI and supports analog trigger. Although it is very difficult to find information on the use of analog trigger for analog output of the tasks, what I've learned so far is to connect the interested analog trigger signal (such as an external noise) on both the AI channel which is used as a source of relaxation (ai0 in my case) and a two-channel (APFI0 in my case) APFI.

  During the test the example above vi, any level of relaxation that I put (even with 0), the task of output did not work at all. No error message is returned either. Just for your information, I do physical tests, not only the software simulation, so no signal means no signal.

  Any help is appreciated!

  I have here is that the solutions to this issue, just want to say thank you to all who have helped me on this subject.

  Use the analog analog trigger output tasks, make sure that the trigger signal (input HERE) is connected to APFI0. There is no need to connect the trigger even signal to ai0 if you do not want to save the trigger signal. However, if you do not want to save the trigger signal, connect the trigger signal to both ai0 and APFI0 with a signal splitter. In the latter case, the task of the AI shouldn't take the same trigger that the task of the ao. This means that you can start your registration with or without a trigger, while leaving the task of ao wait a trigger of some signal. This is useful in a situation that you only want to generate ao task to a certain trigger event, as when a signal reaches a certain level of sound pressure.

• DAQmx: Analog input directly to the analog output at the hardware level

  Hi all

  I searched for a while, but I couldn't find any suitable implementation for what I'm trying to do.  A person where I work introduced me to an interesting challenge.  Is there a way to set up a DAQmx task (or set up otherwise an MIO Board) to route an entry directly to an output to the analog analog hardware level?  You may be thinking, "why the hell would you do?  To reduce the electrical complexity, a colleague would like to concurrently read an entry while 'reproduction' of its signal on analog analog output.  I know that I can easily accomplish this while the buffering by the PC, but they are interested in ensuring that the output signal is also similar to the input at the level of KHz signal, by introducing a minimal difference in phase (shift buffering of the PC).

  For the record, we have for most old maps of the E series here like the PCI-6070E (PCI-MIO-16-1).  I was first asked if it could be done through SCXI, but I figured I would start by asking about the MIO tips.

  This looks like a long shot, and I've never heard of someone at - he never did this, but I thought I'd ask to be sure!

  Thank you

  Jim

  Hi Jim,.

  With the help of our driver is not a means of generating data directly from the FIFO of AI, it must first pass through the software.  You can try the following code to the output of one of THE duplicate on the AO line to see what kind of delay you can imagine.  It is similar to your original with a few adjustments code:

  Use delayed output Version of avian influenza in DAQmx AO

  It seems you need to do, you might consider instead the search by using a voltage follower to isolate the Vout wine.

  Best regards

  John

• How to use DAQmx Read to measure several analog channels

  I have two analog inputs using USB 6221 and I want to measure the voltage of each of them.  I use vi DAQmx-read and I select input analog, 1 sample, several channels, but I do not know how to connect several channels at the entrance of the physical channel.

  Hello, Bernadette.

  For reference - I would recommend ad DAQmx questions here:

  NEITHER Forums: Multifunction Data Acquisition

  http://forums.NI.com/T5/Multifunction-DAQ/BD-p/250

  There are several ways to add multiple channels for a fast task-ni.com look for "select multiple channels DAQmx" gives me this like the hit albums:

  2X8D7F5Z knowledge base: How can I select more than one channel of NOR-DAQmx LabVIEW?

  http://digital.NI.com/public.nsf/allkb/A3A05920BF915F1486256D210069BE49

  Hope that helps!

• DAQmx task start-up delay / quickly generate arbitrary output voltages

  Hello

  (Sorry, I m new to this forum and could not find a reasonable solution by using the search)

  I develop a c# multithreaded application that generates a waveform in the 'background' using output buffering simultaneously, captures the images via a firewire camera and treat them. I have a second channel DA free that I would use when debugging a marker in real-time so that I can check on an oscilloscope which is the relative condition of simultaneous processes, i.e. output a voltage of 1 V while treatment step 1, 2 Volts to processing step 2 etc. or I would be out a short spike at some critical point. This is done using a task as

  DA_Task_sgl = new Task();
  DA_Task_sgl. AOChannels.CreateVoltageChannel ("/ Dev1/ao0", "DA0" - MXVOLTAGE, MXVOLTAGE, AOVoltageUnits.Volts);
  DA_Task_sgl. Control (TaskAction.Verify);
  DA_Task_sgl. Timing.SampleTimingType = SampleTimingType.OnDemand;
  DA_Writer_sgl = new AnalogSingleChannelWriter (DA_Task_sgl. Stream);

  then, when I want to change the tension

  DA_Writer_sgl. WriteSingleSample (true blood);

  A similar technique worked pretty well using Traditional NI DAQ, but with NIDAQmx and the concept of task, it seems that a voltage of output value takes about 1.5 ms (also of time CPU) which is too slow in many cases. With Traditional NI DAQ two consecutive calls to AO_VWrite() may generate a COB with only a few µs endeavors instead. I guess that the delay in the NIDAQmx is mainly determined by start and stop work, etc.

  Is there a way to avoid all this (in NIDAQmx) and more direct access to the underlying hardware?

  (Please Don t tell me that it is a limitation of Windows, NOR-Trad code clearly shows that it was possible, clearly the thread may be interrupted during the output voltage, but is also my treatment, exactly what I want TO check with this technique, but that 1.5 ms the delay is still there!)

  (Currently used card PCI-6014 with NIDAQmx 9.x, but I think that it s not the card which is itself too slow, I can get the update rate Analog > 100 kHz on the string of voltage waveform via DMA)

  Thank you

  Joachim

  Hi fabwes,

  The snippet you posted on request AO.  This means that whenever you write we go and search equipment to generate tension.  Your assumption is correct, the slowness that you see is because of the job template.  Whenever you are calling WriteSingleSample the task is launched, the tension is out, and the task is stopped.  I suggest the following code:

  DA_Task_sgl = new Task();
  DA_Task_sgl. AOChannels.CreateVoltageChannel ("/ Dev1")

  ("/ ao0", "DA0" - MXVOLTAGE, MXVOLTAGE, AOVoltageUnits.Volts);
  DA_Task_sgl. Timing.SampleTimingType = SampleTimingType.OnDemand;

  DA_Writer_sgl = new AnalogSingleChannelWriter (DA_Task_sgl. Stream);

  DA_Task_sgl. Control (TaskAction.Start);

  DA_Writer_sgl. WriteSingleSample (false / * since we are already started, this parameter is essentially ignored * /, tension);

  This slight change gets the load to start the task of the road before start you writing.

• How to determine the number of highlight ' to write ' for DAQmx generate analog output?

  On the configuration of the stage for DAQmx generate analog output, there is a field "value to write.  I can't find any explanation for what it is, how it determines the value to enter, nor what he writes.  I am trying to go through the tutorials and it cling.

  Someone would give an explanation?

  Hello

  To write value specifies the value to write in the channels, lines or ports selected in string parameters. In other words, this value will be the value of your DC output (for example if you enter 5, your output will be 5V). To get information on different fields in SignalExpress, access help"context-sensitive help. A pane will appear in your work environment that displays the coordinates of the field when you place your pointer over them.

  For new users of SignalExpress:

  Generation of DC signals with NI DAQmx devices: step in the DAQmx build, select 1 sample (on request) in the generation Mode dropdown. You can select a programmatic input to generate, or you can remove the check mark from the check box use programmatic input and specify a value for generating in the field of value to write . NOR-DAQmx help also provides additional information about the data generation.

  Best regards

  M Ali

  Technical sales engineer

  National Instruments

• Can what function block I use in my vi to configure a NI USB6008 of ANALOG OUTPUT.

  Hello

  I have a USB6008 that I use to watch the 3 entries. I would like to add the analog output AO0 to control a 0-5 volts. Which function to use in Labview 2010 for this?

  The DAQ assistant let me only to acquire signals do not generate so I need something similar to the daq but Wizard to generate signals do not acquire.

  Thank you

  Andy

  Each task can contain only 1 channel type so a task DI has all the digital input channels and a task to HAVE it cannot contain the analog input strings there is no way to mix these channels in a single task.  You CAN create and run a job to HAVE and an AO task on the same device.

• Is a PCI-6120 card in a computer with linux useful for the analog output?

  We have a PCI-6120, and we want to use in a computer with linux OS, to the analog inputs and analog outputs.  I have downloaded the driver NOR-DAQmx Base 3.2 for linux, and in the file README.txt only analog input is mentioned for this Council. It is possible to use this card PCI-6120 in linux, with output and analog input computer?

  Best regards

  Hey, Gallas,.

  This line in the README file simply refers to the PCI-6120 by its more popular, analog input subsystem (given that it is a simultaneous sampling device, the AI is the most commonly used subsystem). But NEITHER-DAQmx for Linux does not have the same limitations NOR-DAQmx base has. In other words, it supports the ability of analog output on the PCI-6120.

  Kind regards

  Sam

• I need the raw ADC output card PCI-4462 using DAQmx

  I need the raw ADC output card PCI-4462 using DAQmx

  Is it possible or are only regulated units availible.

  Ken Manatt

  [email protected]

  There is a version of 'Raw' DAQmx Read (see image).  This is probably what you are looking for.

  -Alan

  

• How to trigger and outputs analog and digital Outout tasks begins on a counter to start?

  Hello

  I'm trying to synchronize the start of a task outputs analog, a task of digital output and a task of counter. I want to start the counter to serve the master trigger and analog and digital tasks to synchronize his departure.

  I guess I need something like:

  analogOutputTask.Triggers.StartTrigger.ConfigureDigitalEdgeTrigger ("?", DigitalEdgeStartTriggerEdge.Rising);

  digitalOutputTask.Triggers.StartTrigger.ConfigureDigitalEdgeTrigger ("?", DigitalEdgeStartTriggerEdge.Rising);

  analogOutputTask.Start (); Slave 1

  digitalOutputTask.Start (); slave 2

  () counterTask.Start; n / / master

  Where? is a string specifying a command source for the beginning of the task of the meter. However, I can't find what this string. Any suggestions?

  Thank you!

  -Jon

  Just FYI, the solution to this problem as well as some other ones is encapsulated in a short example .NET, I created. It is on the Web site of EITHER:

  http://decibel.NI.com/content/docs/doc-15500

  This project shows how to synchronize all your analogue/digital outputs through tasks and forums in terms of synchronizing Calendar and start clock.

  -Jon