External trigger a continuous pulse train

Similar Questions

• Sync to external trigger in conjunction with a nearest pulse frequency device fixed...

  I am writing an application running a scan frame. One axis of the scanner runs at a fixed frequency. I use a scanner high speed 5105 to get the data. The slow axis of the scanner is controlled by a servo with an analog input. I have will probably use an M-series card for analog control, but can also go with a 6713 (output only) or another Board. Fixed frequency Analyzer provides a clock line, I want to use to drive the 5105. In addition, the analog card must be synchronized in this. The entire system should be able to accept a trigger external devices, as it starts scanning at the edge of clock on next line.

  I'm not quite sure about what would be the best way to do it. External triggering from other devices will be an indeterminate pulse width, so I can not just use it as a portal for the line clock. I am reluctant to do it in software (IE via the detection of changes on a digital line) because I want to be reliable started the next clock pulse. I have taken into account things like a counter/timer with a relaxing break, but which could lead to drift between the narcotics control and frequency scanner fixed. It seems just more complex that I think it should be, and it feels like I'm missing a simple way to do it.

  Any suggestions?

  Hi cshl,.

  Good to know - the 5105 has a duty cycle of tolerance of 45-55% (mentioned on the page of the form), so that is why you cannot change clock speed from 3 to 12 MHz on-the-fly (though if you make small incremental updates over time, it would be theoretically possible).

  With the additional information in mind, you might want to try the following on the 5105:

  Use the external trigger as a trigger of departure (arm of acquisition).

  Use the line as a signal reference clock (with a position of 0 samples for reference ~ 7500 are after initiation).

  The problem with this is that you will have to re - trigger on each line - 5105 has a 2.4 rearm us time (also mentioned in the page on record).  If this is unacceptable, another way that I can think of is to use a clock to external reference in PLL internal clocks of the bezel to.  If you can provide a stable, a clock accuracy 50 ppm which is synchronized with your scanner within reach, would solve the problem of drift over time without having to re - trigger on each line (only acquire data continuously).  This clock frequency must be between 1 MHz and 20 MHz in steps of 1 MHz.

  We have no Council can take in an external variable clock up to 12 MHz (on-the-fly), but if you wanted to compromise a little bit the 6115 can enjoy up to 10 MHz, and has no obligation to cycle to 45-55% so it's maybe interesting look in.

  As far as AO goes, I assumed that the clock line is declared after the quick scanner has completed his turnaround (ideally you do not update the zone of OCCUPATION during the lead time).  If you have a signal Analyzer that you can use instead probably easier.  If not, our peripheral series M and X series (but not the series AO 67xx) offer reference clock feature so if you go with the idea of reference mentioned above clock it may be easier to simply PLL the clocks together.  These cards in a PXI chassis or are they PCI form factor?

  I don't know what you mean by the sticking point about the need for two triggers.  I think the idea is that we use the external trigger to arm the 5105 and clock line to trigger each record.  However, if you do not need to generate a pulse double based on the clock of your line then you can use counters to do (our counters are redeclenchables with time to rearm in the ns range).

  Best regards

  John

• Continued use of digital dashboard to stop a generation pulse train

  Hello

  I need to generate a train of pulses for a period of time. However, this period is variable, and because of that I can't

  Use the finite number of samples.

  The pulse train must be output depending on the State of the digital I/o. When the line output goes high, must be output of the pulse train.

  and when he goes down the pulse train should be stopped.

  I use a USB-6212, but is already using one of the available counters for the measurement of pulse width. I tried to do a

  AND logic with the pulse train and line activate, but due to the execution time of vi this solution modifies the pulse train

  frequency, which is not acceptable.

  Thanks in advance,

  Mariana.

  Hi Marianne,.

  Your previous message mentioned "line in/out" (in the singular) and "enable line" (in the singular), isn't "the i/o lines" (in the plural). Are the two edges on the same line in/out? Or are they on separate i/o lines (for example, climbing on PFI0, falling on PFI1)? Can you clarify your needs?

  If the fronts and sides come from the same line of output, then a relaxing break seems to do what you want: cause the meter generate impulses while the input/output line is high and cause the meter to stop while the input/output line is low. However, if you start the job, while the input/output line is high, it will immediately start out impulses. If you want to wait the first front line input/output to generate impulses, you can use a trigger 'start of arms' (which is just below "break" in the node property). When the trigger 'arms beginning' arrives, the meter will be armed, and therefore, the task uses the break to determine when to generate impulses. Using pause and start the same counter task returns error-200146, "put in Pause and start triggers cannot be active in this task," but using break and triggers 'arms beginning' in the same task of counter should be correct.

  If you want to increase the edges of PFI0 to start the meter and the fall of the edges of PFI1 to stop the meter, which is more complicated and it will take thought additional (and possibly additional hardware).

  Brad

• Problem with the generation of two internal counters pulse trains

  Hello

  I do a control of temperature for two heaters, OR 9472 (output module digital), NI 9271 (RTD for measuring temperatures) and cDAQ-9174 chassis. So, I use the internal meter NI 9174 to generate two pulse train on the outputs (I tried with both cases-> pulse continuous and finite). Before that, I have two separate PID.vi, in which each sent the percentage of cycle of obligation for the two tasks of pulse generation (I configured these tasks with the physical channel cDAQ1Mod1/ctr0 and cDAQ1Mod1/ctr1). The problem is when I run the program, because the application initially worked fine, but after a few seconds the communication between the chassis and the application is not respected (no error message, but the external LEDs on the NI 9472 module had been disabled and stopped too NI 9271 module temperature readings). Then I tried to stop it with a 'Stop' button, but nothing happens. After, I abandoned the race and still nothing happened. So, I finished the Labview program with the Task Manager and a message appeared "reset VI: xxxxx". Finally, I have to restart my computer to run the program again. Can anyone help with this please? If you need more information, let me know.

  Kind regards

  Hi Luis,.

  I have the error cluster connected. But I solved my problem in a different way. I don't know why, but when I configured my RTD module with the DAQ assistant to test some of my design in a new file in VI, the RTD module works fine, but if I copy the entire program logic (include my DAQ assistant) back to my main VI folder and run the application, only for communication between my DAQ hardware and my software works there shortly. So I solved my problem set up any device or module in the same file from the application again and problem disappears.

  Thanks for your help.

  Luis C.

• How to connect to the list of the pins for a redeclenchables pulse train

  Hello

  I'm relatively new toDAQmx, especially for the counters. I have problems to determine what pins to plug on the DAQ card. I would like to run the vi described here, but am not sure how to connect the card. I looked at the manual of the X series for the pinout descriptions, but I don't know how they apply to the program on this page. When I connect DOOR a meter, THE, A, B pins, etc.?

  Any input on what to connect or pages that may make how to connect the counters would be very useful.

  Thank you.

  Your most recent post of links to an example more advanced sounding & I recommend that stick you with something simple to start.

  Your first post links to such an an example where the signal of pulse train going out of Ctr0_Out.  Ctr1 is used to make the trigger and the 'break' (enable / disable) Ctr0.  However, much of this stuff is configured using some features of DAQmx such that you don't need to physically connect the pins between the two counters.

  Only physical wiring that you need is to plug your physical digital trigger to the PFI1 signal and connect Ctr0_Out to some external thing must receive them.  As long as your device is called "Dev1", I think this example to work.

  I know there are some docs useful for more general info on the pins meter & behavior, but I don't remember quite so that I have not watched for them for many years.  Meanwhile, here is a * little * bit General description I wrote myself once.

  -Kevin P

• Two pulse trains with delay of fixed phase using USB-6216

  I need to generate two pulse trains of continuous with the 2nd train of pulses at a set for the first time. Is this possible with the USB-6216?

  Yes it can.

  You will need to set up a dummy analog input task and set the two tasks of counter to serve their trigger start of AI/StartTrigger.  Your first meter will start immediately, but your second task is to counter, specify a value for the terminal 'initial period' of the DAQmx VI create channel.

  This 'initial period' will be in a few seconds and the period after receiving the start trigger that starts the second pulse train.

• problems with several hr2000 + external trigger mode

  I hope someone can me halp on this problem:

  I need to acquire spectra with two hr2000 + and a nirques256 with labview external trigger mode.

  The external trigger mode is done by another pc and also the train of pulpse generator.

  If a trigger after I'm going to generate a 100 impulse every 20ms for each device through a dedicted Council.

  If I only work with ghosts at times things works fine and the system is very stable, BUT if I work with two or three spectres by now I have a really strange (maybe for me) problem with the timeout.

  This is due to an incorrect number of pulses:

  If I work with two device then I need to produce pulses of 200 each 20ms but my spectrometers provide data every 40ms, but I need to equip every 20ms

  If I work with threedevice and then I need to produce pulses of 300 each 20ms but my spectrometers to obtain data each 60ms but I need to equip every 20ms

  Thus, in this way, I lose the synchronization of the three councils.

  An options may be to use a dedicated pc for each device

  I acquire the signal via usb and the problem is maybe duo to the bus

  I think maybe the problem is duo to the vi block! Maybe I can use single istance at times when I call the procedure

  Thank you

  I just solved the problem: it was a problem with reentrancy

  Default LabVIEW use not reentrant execution

• initialization of the fgen on external trigger

  Hello

  For NI_Virtual bench with the BNC switch, we can trigger the function generator to start the square wave? I mean, I want to relax, so I have the beginning of the square wave

  You cannot trigger the function generator to start in response to an external signal.

  However, you can export a signal only pulses when the FGEN starts the external trigger BNC. You can do this with the entry point to 'Dig deeper the Signal to export'.

  Kind regards

  William Earle

  OR R & D

• external clock or wave pulse or sinusodial?

  Hello

  I'll plug an external clock to 6711 map source. But I wonder if the source should be trains of pulses (wave squre) or it might be vague sinusodial. When we say the frequency of the clock, it means the occurrence of the rising or falling on board but not the pulse, right? And what is the range of voltage for the clock signal?

  Hi dragondriver

  The external clock should be a pulse train, not a sine wave.

  When we talk about frequency, as you said that it: the appearance of rising or falling edges within a period determined.

  Voltage range must be from 0 to 5V.

  Concerning

• Redeclenchee HW with line Enable Pulse Train

  I am using the 'Multi-multifunction-Ctr Retrigg Train generation of impulses for the Clock.vi sample' in the Finder for example LabVIEW to sample a waveform. It worked great, but now I need to sync my purchase with another piece of equipment. The material defines a "Enable" high TTL line when it is ready to acquire and I need to start my purchase at the pulse of available next synchronization. The option "Activate" is low and I have to stop acquiring after than the gust / the current image is complete. I tried to use a line of 'Pause' and a 'Digital Plan' trigger but doesn't seem to work with a finite pulse train. Since it kinda is diffficult to explain in the text, I have attached a waveform.

  Any suggestions? I use an inLabVIEW DAQPad 6016 8.5.

  I would treat differently the digital. If you watch the digital parallel and just read single points, then you will have a quick way to signal to the loop to HAVE the enable option has been low. I added an untested VI which should give you the idea. There is probably a better way to manage stopping both loops, I just did a quick and dirty method. After watching your VI it dawned on me that you could build a machine of the State where he's just looking for available samples then actually starts reading, and once there are no samples available after a certain period of time you would stop. You would still need the door AND but would not need to worry monitors the enable line. This would be probably as fast that monitors the line to activate it if.

  For a door AND every door TTL AND must accept a 5 V power supply. If I remember just a 74LS08 should work - if you only need the one you may be able to get a free sample.

  see you soon,

  Andrew S

• How to generate a variable frequency pulse train constantly

  Hi all

  I am using NOR-USB-6259 (BNC) to send signals of impulse to the position of a servo with labview motor control. The position of the servo-motor control follows these rules:

  1. The pulse train number determines how many degrees the motor;(par exemple la position angulaire dele de moteur)
  2. The pulse frequency determines how fast the engine is running; (for example the engine rotation speed)
  3. Digital determines the direction of rotation of the engine (for example in the clockwise or counterclockwise)

  My question is when I have to continuously generate a body finished, train signal in a period of time. Here's a sample:

  Time (s)	Number of pulses	Direction of rotation (1 clockwise, counterclockwise 0)	Frequency
  0-1	923	1	923hz
  1-2	3540	0	3540hz
  2-3	1751	1	1751hz
  3-4	2663	0	2663hz
  4-5	353	0	353hz
  5-6	1017	1	1017hz
  6-7	3436	1	3436hz
  7-8	10 p	0	302hz
  8-9	1513	1	1513hz
  9-10	570	1	570hz

  Here is the explanation of this table, the motor continues to turn clockwise for 0 ~ 1s. When the time reaches 1 s, the engine simply fill out the rotation of 923 pulse signals. And then the engine starts to turn clockwise for 1 sec ~ 2 s. When the time reaches 2 s, the engine simply fill out the rotation of 3540 pulse signals. So we can see that the speed of rotation of the motor to 0 ~ 1 s is different from the speed in 1 ~ 2 s. Namely, the frequency of the signal from pulse to 0 ~ 1 s is different from the frequency in 1 ~ 2 s.

  I already use the DAQmx counter output, it can simply generate pulse signal with some numbers and some frequency only once. The attachment is the vi that allows to generate a digital pulse train finished the meter output channel and frequency, cyclical, delay report Initial and idle state are all configurable.

  How can I continuously generate a series of pulse train with a variable number and frequency for a certain period of time.

  Thank you very much for your help!

  The frequency 'on the fly' control requires intervention of software and can not guarantee a specific number of impulses for each rate (which I assume you want because it's an engine step by step).

  If it was me I would do one of them instead:

  1. use the digital output for everything.  The digital output at a higher clock rate and build the waveform to give you the desired number of steps and management.  This method would give less temporal resolution than others.

  2. use a task of meter output, 1 section at a time.  Reconfigure and restart the task for each section after the management output setting.  This method could introduce a delay between each section.

  3. purchase of new equipment - X series supports put buffered outputs of meter that can do what you ask.

  Best regards

• Counter/Timer Pulse Train generation

  Hello

  I'm having some difficulty to understand why a particular VI I does not work (upper part of the image below), I was wondering if someone could give me an idea of the cause of the error message.  I have a counter/timer, which I use to generate a pulse train.  It works very well on samples of "continuous", but when I turn it on to 'finished samples' I get an error of "resource is reserved" when it comes to the DAQmx VI of 'play '.

  I made an another VI (lower part of the image) and it works very well with finished samples.  So basically I wonder what's different on finishes versus continuous sampling which could cause a resource to book or not. (the Board of Directors is a PXI-6281 if it matters)

  Thank you

  Adam

  

  OK, I just looked through the manual and it seems that when you do a finish on a counter pulse train generation, the jury must in fact to divert the OTHER counter.

  This may have been aparent earlier if the error message about what resources he tried to get was more prolific.

  In any case, problem solved I guess.

• Acquisition of a sequence of images based on an external trigger.

  Hello

  I have a photonfocus MV-D1024E-160-CL-CMOS camera. I'm generating a square signal of a NOR-DAQ. I want the camera to image acquisition on each falling edge or rising edge of the signal. I've seen examples related to IMAQdx drivers to get a sequence of images using an external trigger like this, but there is no examples for the IMAQ. If anyone can post a few examples, it would be really useful. I saw the example of component snap off and tried to use it. But I think that if I use the encoding that is used in this example it will only launch the sequence rather than what I want. Thanks in advance for anyone who can help me in this regard.

  Hello

  Have you acquired images triggered in MAX when using the pulse width to determine the exposure time? It is always good to make a step back with these changes and make sure things are running at a more basic level.

  -Zach

• analog input external trigger 6015

  Hello

  I was able to configure my 6015 to accept an external trigger to start a measurement of analog input (with a # set of samples and freq).  However, what I want to do is to set up so I can send a 20 kHz signal to the trigger, and whenever the trigger detects the signal, the device would take a measure of the tension of each of the two channels.  He would then save this memory on board and allow me to read the data later.  That's what I can't figure out how to do.

  If he put in place such as I have an asynchronous callback and read data after each pulse, it takes too much time in my application.  I want to get a measure for each external trigger pulse (the freq may vary higher or lower, it's why I can't put just a freq - I need to use the trigger) and these data saved in memory on the card for me to pick it up later.

  Is this possible with the 6015?  Another tip?  If so, can you please show a few snippets of code in VB.NET or c# .NET?

  Thank you

  Joe

  Hey Joe,

  I think that your application should work fine with the 6015. I mentioned only the buffer size as previous your post said 'I want... these data stored in memory on the card to grab me afterwards,' and especially supported in NOR-DAQmx devices (including the 6015, PCI E Series, the new series X PCIe and PCI M Series) don't work that way. They have permanently transfer data in a buffer in the memory of the host throughout the acquisition PC, and they have enough buffer on board to avoid negative/overflow buffer overflow errors at their maximum supported rate

  Brad

• several finite pulse trains of TTL

  Dear members of the forum OR,.

  We have just received a chassis NI SMU-1073 with an SMU-6361 OR switched in PXI1Slot2 and a shielded connector BNC-2111. Aims to generate trains of three TTL pulses to control a laser, sound and shock via Matlab Application. I use the C OR-DAQmx API with Matlab MEX to integrate C in Matlab code.

  I came up with the following code in the examples in C to generate a pulse over TTL time-based train:

  initialDelay float64;
  
  float64 lowTime;
  
  float64 highTime;
  
  uInt64 periodsPerTrain;
  
  float64 taskMaxTime = (lowTime + highTime) * periodsPerTrain + 2 * initialDelay;
  
  Configure Pulse
  
  DAQmxErrChk (DAQmxCreateTask ("", & taskHandle));
  
  DAQmxErrChk (DAQmxCreateCOPulseChanTime (taskHandle, "PXI1Slot2/ctr0","", DAQmx_Val_Seconds, DAQmx_Val_Low, initialDelay, lowTime, highTime));
  Configure the Pulse Train
  
  DAQmxErrChk (DAQmxCfgImplicitTiming (taskHandle, DAQmx_Val_FiniteSamps, periodsPerTrain));
  Departure Train
  
  DAQmxErrChk (DAQmxStartTask (taskHandle));
  Wait for execution
  
  DAQmxErrChk (DAQmxWaitUntilTaskDone (taskHandle, taskMaxTime));
  Clean
  
  DAQmxStopTask (taskHandle);
  
  DAQmxClearTask (taskHandle);

  I'm stuck with two problems:

  1.) SMU-6361 has 4 meter signals ctr0-3. With the above code, I can generate separate tasks for each TTL signal and evoke them consecutively with DAQmxStartTask. But in this case, I guess that the tasks are not synchronized. Can I use the clock signal to synchronize the other 3, for the tasks of each is triggered at the same time? What will be the right way to do this with the C API? The step of the smallest of the discrete-time in the example is 500ms. see the picture as an attachment to check how the TTL signals should look like.

  (2.) what is my physical connector on the BNC2111 to outsource these signals.

  / PXI1Slot2 / ctr0-> PFI12/P2.4

  / PXI1Slot2 / ctr1-> PFI13/P1.0

  But what ctr2 and ctr3? How can I configure the physical connector outsource? Is there a function to specify that?

  Thank you in advance for any advice, suggestions and directions!

  see you soon,

  go9kata

  

  Hello go9kata,

  for your second question, with the BNC-2111. You can route the signal from the counter for

  lines PFI avialable on the block of connection BNC 2111 with the following syntax

  DAQmxErrChk (DAQmxSetCOPulseTerm(taskHandle,"/Dev1/PFI0"));

  I hope that helps, if not please let me know.