Digital input triggering

Hello

Is it possible to trigger action digital input using the signal I want to measure? In the example:

I want to measure PWM on P0.0 after first rising edge PWM on P0.0, but using only this line P0.0 (no PFI in use, only one used digital entry).

IM using X SERIES USB-6353.

Some DAQ cards can trigger on analog edge of the signal you want to measure. If a DI data extraction, it is possible to select only the PFI or similar as trigger. What is your application? What you want to achieve?

I can imagine you could workaround: record streaming samples of DI and do a SW trigger in your program, so you can get the same samples prédéclenchés (as in a digital oscilloscope).

Tags: NI Hardware

Similar Questions

  • Digital inputs only noisy when the laptop is plugged

    I had problems with loops of Earth and power supplies for laptop in the past.  But it is the first time I got it so wrong that it makes the digital inputs which are both related to the ground and the debounced software cannot be used.

    It is NOT material OR.  It's a DT9816 of data translation, a USB DAQ Multifunction with small budget.   The laptop with the problem is a refurbished Dell, with a very obvious not Dell PSU who throws to the top of the warning in the BIOS and scales back from the processor.  (Danger Will Robinson!)

    The problem with the digital entries shows only upward on the Dell when it is plugged into a power outlet.  On all other machines and with the printer unplugged Dell, digital inputs floating.  But those that I have attached to the Earth is rock solid and work very well.

    What surprises me is more than the noise is so bad that even tied to the ground with a half second debounce, I get always false triggers.  I have not brought to power, but considering that it sounds really loud, I suspect that it looks pretty bad.

    I think I'll try a powered USB hub.  If this does not work, then I think that the customer will have to replace the power supply on the laptop.

    However, I was surprised.  I used a lot of USB DAQ hardware, and it's the first time I've never seen a problem like this.  The NI USB 6002 I tested on this same laptop does not seem to show the same problems.  Even if it is true that this is a different software and the test was brief.

    I'm curious to know if other developers have found something similar in the past.

    I can confirm that using a USB hub external powered eliminated the problem of noise in the original post.

    Interesting things.  I had not seen this before.  Now, I wish I had again the NI DAQ USB I had here last week so I could test that.

    Looks like I'll use a hub powered on this project.  But I think I will recommend always replace this power.  Although a lot of noise coming from the power supply, probably isn't good for nothing plugged it... or even sitting near him.

  • The iMac has a digital input?

    Hello

    I searched for centuries for the answer to what I thought was a simple question - the iMac has one digital input (optical or other)?

    I know that the headphone port doubles as an analog audio to as well as an optical digital output, but this port also accepts input optical? If not, is it possible to enter a digital signal via a USB port?

    I have an iMac (20-inch, mid 2007).

    Thanks to all who can help.

    AL

    Yes exit usb audio and are truly comprehensive external soundcards, they can have any type of entry and exit of the machine to be desired that they have

    and if they do a driver of OS x for him it's just a matter of connection installing the driver and choosing the entry in system preferences for being that

    https://Flipboard.com/@mariahlolas/top-10-best-USB-external-sound-card-adapters-for-Windows-and-Mac-2016-2017-npa5lltvz

    If the audio minijack that also take in charge the headset for iPhone I believe support the digital input and I don't know if

  • Digital input to Toshiba 46TL-> no analog audio output to amplifier

    Hi all

    When I connect a video source (e.g. computer laptop via DLNA) to my 46TL, output TV audio analog (red/white taken connected to an amplifier) does not work.

    It does, however, watching television.

    Is it possible to configure the TV to read the audio data from digital input (HDMI/DLNA) to the analog output?

    Thank you for the help

    Not quite what series of TLxxx you have, but for example the TL938 supports a digital (optical) audio output port that provides a digital audio signal.
    Why n t connect the amplifier to the TV using this Jack?

    Connectors for component video / audio to the rear of the TV are the ports of ENTRY and not the OUTPUT ports. So, you can send an audio signal to the TV and not the amplifier output.

  • Interrupt with digital input

    Hello

    I am relative new to LabWindows.

    I have a program that starts when I press a button. The program controls a motor. Now I press a button on the motor and the program must cease (Safty Stop). The button is connected to a digital input on my card (PCI Express 6343). Now, I have the question, how do I program the interruption? I know not how do in CVI (controls the digital input whenever the program runs).

    I hope someone can help me.

    Best regards

    The starting point must be to look relevant examples that NEITHER provide:

    ReadDigChan - ChangeDetection.prj

    and

    ReadDigChan - ChangeDetectionEvent.prj

    However, I must advice against using a PC as a "Safety Stop". As a general rule, the PC are completely inappropriate to the core functions of security, unless you follow the standard IEC 62304 relevent to the letter. Tip: it's hard to do with a PC. To implement safety functions such as emergency and interlocks stops you buy much better a specialist dedicated safety relay and following the instructions of the manufacturer. If life-threatening energy (either electric or medcanical) may be present, then consult a professional engineer.

  • How can I set up a digital input task to read continuous samples?

    I am trying to create an exclusively digital task that will make digital readings at a rate timed by the material using a PCIe-6509. However, when I try to put the task timing as follows (which works on a PCIe-6509), I get the following error:

    Requested value is not supported for this property value. The value of the property may be invalid because it is in conflict with another property.

    Property: NationalInstruments.DAQmx.Timing.SampleTimingType

    Required value: NationalInstruments.DAQmx.SampleTimingType.SampleClock

    Possible values: NationalInstruments.DAQmx.SampleTimingType.OnDemand, NationalInstruments.DAQmx.SampleTimingType.ChangeDetection

    Task name: DigitalInputTask

    State code:-200077

    The relevant parts of my code are:

        public class DigitalInputReader: IDisposable
    {
    public DigitalInputReader()
    {
    dataReadyHandler = new System.AsyncCallback (DataReadyEventHandler);

    daqmxTask = new DigitalInputTask();
    daqmxTask.Configure (Globals.NI);

    daqmxTask.Control (TaskAction.Verify);
    daqmxTask.Control (TaskAction.Commit);

    daqmxReader = new DigitalMultiChannelReader (daqmxTask.Stream);
    }

    public class DigitalInputTask: task
    {

    public DigitalInputTask(): {base ("DigitalInputTask")}

    public virtual void Configure (NiConfiguration niConfig)
    {
    <= niconfig.digitalinputs.count="" -="" 1;="">
    {
    String physicalChannelName = niConfig.Device + "/ port" + niConfig.DigitalInputs [i]. Port.ToString () + "/ line" + niConfig.DigitalInputs [i]. Channel.ToString ();
    String nameToAssignToChannel = niConfig.DigitalInputs [i]. Name;

    DIChannel ch is this. DIChannels.CreateChannel (physicalChannelName, nameToAssignToChannel, ChannelLineGrouping.OneChannelForEachLine);
    c. InvertLines = niConfig.DigitalInputs [i]. InvertLines;
    }
    var signalSource = "";
    This. Timing.ConfigureSampleClock (signalSource, Globals.MachineSettings.SampleRate, SampleClockActiveEdge.Rising, SampleQuantityMode.ContinuousSamples);// Globals.MachineSettings.SamplesPerChannel);
    }
    }

    The last call to Task.Timing.ConfigureSampleClock, it's which throw errors.

    Of the options available, or SampleTimingType.OnDemand or NationalInstruments.DAQmx.SampleTimingType.ChangeDetection provide the same precisely timed calls that I am familiar with the analog input interruptions.

    How is it possible in a digital task?  I mean, it seems that I could set up another task to do call by material for the production of a clock signal and use the ChangeDetection synchronization mode, but this seems a bit complicated for what should be easy to do.  What Miss me?

    Update: I thought about it.  You cannot call ConfigureSampleClock when the digital input card is a device of 650 x, because these devices have any automated examples of clock.  They are configured to run in mode default finite samples.  You must make all sample synchronizing with these devices in the software.

    Be cautious, however, because the .NET timers ensure they put any faster than their scheduled interval.  In practice, they are usually 5 to 10 ms slow by tick.  This means that if you want to read samples every 100 ms by sample clock, you'd end up reading all 108 ms samples.  All counters based on the elapsed time and number of samples would be away after a few seconds of it.

    Instead, you must do one of four things: write a doggone driver that runs in ring 0 and interfaces with the PCIe card in the required interval (i.e. on NC, not you, in practice), tolerate the inclination of the clock, use a multimedia timer as an interruption audio or video that is more likely to respond to the correct interval, or , my solution, an accurate clock allows you to set the interval of the timer.  I wrote the following code to the timer:

    var CorrectiveStopwatch = new System.Diagnostics.Stopwatch();
    var CorrectedTimer = new System.Timers.Timer()
    {

    Interval = targetInterval,
    AutoReset = true,
    };
    CorrectedTimer.Elapsed += (o, e) =>
    {
    var actualMilliseconds =;

    Adjust the next tick so that it's accurate
    EG: Stopwatch says we're at 2015 ms, we should be at 2000 ms
    2000 + 100 - 2015 = 85 and should trigger at the right time
    var StopwatchCorrectedElapsedMilliseconds = newInterval +.
    targetInterval-
    CorrectiveStopwatch.ElapsedMilliseconds;

    If we're over 1 target interval too slow, trigger ASAP!
    <=>
    {
    NvelIntervalle = 1;
    }

    CorrectedTimer.Interval = NvelIntervalle;

    StopwatchCorrectedElapsedMilliseconds += targetInterval;
    };

    I hope this helps someone.

  • How to combine several digital inputs for playback?

    Hi comrade Labview users.

    I just started using LabView and I am very new to it. I know him understand how it works and you have something to work, but I need to be more effective.

    I use DIO96H - USB DAQ Measurement Computing, which includes 96 digital inputs. I use the DAQ to acquire the activations of relay and record the number of times the relays flips.

    Basically, I created a digital input read and then copy & pasted 95 times... it works but I know that's not the best way to use LabView.

    How can I change the digital input (Di1/1stPortA/dev0) in multiples so that it iterates through all 96 channels without copying and pasting the same pattern over and over again?

    Leon

    You have the correct polymorphic instance for playback? Once again, for the material OR it would be a NChan Read. There should be a similar choice if I remember correctly.

  • Digital input current limits

    Hello

    After reading everything that specifications and manuals, I decided to ask a general question.

    In the data sheets, user guides I've read, in general, there are two warnings for DIO:

    -Do not connect the outputs digital circuits which operates above the limits.

    -Do not drive the line with tensions outside its operating range.

    Generally speaking they tell me I need to know when dealing with output and voltage when dealing with entries. So I have this question, can I wire a power supply for digital inputs directly without exceeding its "beach of normal operation and without any protection circuit? In fact, my feelings, this is not possible. But why certain documents produced clearly mention that the impedance internal inputs while that of others is not clear those? How can I determine if I can connect a signal directly to an entry (for example USB-6525 indicates a current limiter circuit, but I don't see a clear explanation in the datasheet USB-6251)?

    As long as the input voltages are within specified limits, no damage will be the DAQ hardware. Logic devices often have two lines of non overlapping input, one for low input and high input. If the input voltage lies between the beaches, the performance of the device can be unpredictable. Also, check your power supply to make sure that this doesn't not exceeding when turned on or off as that could exceed the DAQ limit.

    Lynn

  • Reduce the period of sampling of the digital inputs of NOR-USB-6009

    Hello

    I need to read a line of digital input in the NI USB-6009 using NOR Express 2013 Signal box. I selected 1 sample (upon request) as acquisition mode. I need to define a smaller sampling period as 1 MS, but it gives error too short sampling period: "the current sampling period is too short.  Please specify a longer sampling period. ».
    I do not understand the reason for it and a way to slove this.

    Any help would be greatly appreciated!

    Thank you!!

    The 6009 doesn't have a clock that you can set for a sampling period. According to the specifications, the digital I/o is software programmed - sample on request you use now. I'm not at all familiar with SignalExpress but I don't think that you can find near a reliable khz sampling frequency on Windows or any other os non-deterministic.

  • NEITHER 6501 digital input

    Hello world

    I use an NI USB-6501 and I'm trying to understand how to read the entries.

    I used this card to generate output using the example vi write Chan digging, it works fine.

    Now, I'm trying to use the example of reading dig Chan vi to read an input voltage. But it seems that, by default, the map reads 5V (a 1 logic) as entered on each pins, even if nothing is connected to them. I tried to connect the output to the input, use a relay to see if it detects a change in the entry, if we send a voltage or not, but it changed nothing. It still reads 5V anything.

    Can someone help me understand how to be able to read an entry? This problem has happened to someone else?

    Thanks in advance.

    Frédéric

    If you dig through the data sheet, you will see that there is a 4.7kOhm shoot all digital inputs.  So with the floating inputs you will get a high (logic 1).

    As Dennis have already said, wire your digital output directly into your digital input.  So everything that you set the output that you will read on the entry.  I don't know what you do with a relay.

  • 6259 switch digital input to output

    Hi all

    I use the NI PXI-6259. One of the digital inputs I want to switch to digital output, send a serial code and switch again one digital input.

    Does anyone have experience with this kind of configuration change during execution of the VI program.

    Thank you

    Basically delete the task that he had as an input, create another task DAQmx with channel configured as output, this task, erase it, create the task with channel configured as an input.

    If you need a tight with switching schedule, I wouldn't recommend this Board.  You may need to set up a Council of RIO with LabVIEW FPGA.

  • virtual digital input problem

    Hello

    I'm learning about labview data acquisition. So, I made a base for digital vi, with a virtual digital input device. For some reason any I can not output anything other then zero, but when I run the daq assistant (when you install assistant daq) Boolean values between 0 and 1. But, in my VI I can't get any other input then set to zero.

    I enclose my VI.

    Thank you

    You should associate your stop button at the entrance to Stop on the DAQ Assistant.  You are openening and close the task each time when you do not do this.  According to me, which is also reset the activation/deactivation of the simulated device.

  • Digital input maintains to 5V

    Hi all

    I meet a scenario where the digital input on my DAQ card channel giving 5V when I measure between the channel and the ground. As a result, I was not able to read the digital signal. This happned in the past, a few months ago and my work around it is to switch to another channel. This time, I feel the same thing using my FlexRIO + OR 1483 module. There are four DIO channels and I have them configured so that came in 2-channel and 2-channel output is. Initially, everything worked fine, but somehow, these last two days, I wasn't able to read DI channels. During the inspection, we discovered that DI (at NI 1483) channels provide 5V.

    I hope someone could shed some light on the phenomenon.

    Please advice.

    BEA

    Take a look at the spec, maybe a pull from the top of resistance?

  • Static digital inputs N samples

    Is there a way to set the sampling frequency during the acquisition of N samples from a digital input static? I use a USB-6216 data acquisition but the only option of timer is on request.  It seems that daq samples randomly I use acquire N samples.  My goal is to have a level of synchronization between my analog and digital input data for sampling at 500 Hz.

    Hi UpNSmoke,

    Unfortunately, the 6216 can only run DIO clocked by the software. If you use Windows or another non-deterministic operating system, you will be unable to achieve very tight synchronization (or high sampling rate). If you want your two analog and digital input tasks be hardware synchronized, I would recommend something looking from the x 622, 625 x or better yet, the new X-Series range.

    Hope this helps,

    Sean

  • Playback of digital input [FPGA] - NI 9401 - questions?

    I'm having some trouble with the digital input NI 9401, which is to have a uniform reading. I have a photogate that power of a digital output is turned off and goes in to a digital input module, but I can't read the entry several times. My LED flashes once and never again will blink until I restart my CRIO or recompile. I have launched the ports of entry and exit, their market and constantly for loop. Any idea what's going on?

    Hi Allan,

    Why you "light up" a channel of entry?

    Writing a value to a DIO PIN is usually for outings!

    What is connected to your PIN DIO 5? Have you checked the entry with a DMM measure?

    How long the impulses are measured with this entry? Do you really you can see short pulses of light flashing?

Maybe you are looking for

  • second row of keys not working only not on the apple bluetooth keyboard

    The second row of keys keyboard bluetooth of iMac (the Board older with batteries) do not work. Thoughts? Thank you LGS properties

  • connect my new samsung moble to computor

    my computer not regognise not my new samsung

  • WRT54GS - Internet cannot be found.

    I have a wireless desktop computer and I keep getting the message: "connected to access point but internet cannot be found» Internet is Comcast. The router and the PC are about 25 feet apart on different floors of my house.

  • Show all windows

    I found a personalized on my logitech keyboard, which will show all currently open windows, placing them adjacent to each other and scaling the dimensions of the window, then all the windows will be adapted to the screen. The function is similar to O

  • Problem with QDE IDE

    Hello I just downloaded the new sdk native gold. uninstalled previous sdk and installed a new. While building the application, I'm not able to see the different perspective view. Not able to pass n/b of the design view, split etc. I want to see how m