Start trigger

Similar Questions

• Restart waveform immediately start trigger

  I create a waveform 50 ms with an SMU-5451 in SMU-1078 chassis with a controller of SMU-8840 running Labview RT.  The waveform is currently triggered by a pulse of a counter of data acquisition because the timing of the wave must be closely synchronized with data on the acquisition of data collection.  However, this approach is problematic because it is difficult to produce a continuous of the 5451 signal when it is triggered in this way.  If the waveform is exactly 50 ms long, will miss the start trigger.  I can tolerate losing at the end of the wave, but I can't tolerate having a gap in the output, and I need the waveform to start exactly on the edge of outbreak of 50 ms.  I can configure the 5451 to accept a trigger start and restart the wave immediately rather than wait for the current iteration of the waveform to complete?

  I guess I could use a complete the 5451 event to trigger the acquisition of data instead, but I guess there is a way for me to do what I want.

  Are you familiar with the mode "script"? You might be able to use this example script:

  script restartWhenTriggeredScript
  
    Repeat forever
  
      generate wfm
  
      break on scriptTrigger0
  
        Repeat forever
  
          generate wfm
  
        end repeat
  
      end break
  
    end repeat
  
  end of script

  Basically, the idea is that, when it receives a trigger, it stops the execution of the inner loop and finish the iteration of the outer loop. Then it will start again from the beginning and to the inner loop.

  Please let us know if that fixes the problem.

• analog output digital start trigger the api c

  Hi, I'm trying to start analogue output based on a digital trigger (either PFIO or a PXI line) I can make this easy in LabVIEW.  However with the C API (through the Python wrappers), the problem is when I call DAQmxBaseWriteAnalogF64, writing will always be timeout that the acquisition was not triggered.   However, I can't call it after the trigger occurs, because obviously, it will be too late.

  I can't find any examples of C API where the analog output is triggered a digital triggering.  I can find for the analog input, but is fundamentally different that you can CONV read anytime after the trigger occurs.

  Python code as follows (functions are equivalent ot C API, even if you have no need of ot pass the task handle such that it maintained as part of the Task object)

  # create analog output task
  analog_output = Task()
  analog_output.CreateAOVoltageChan("Dev1/ao0","",-10.0,10.0, DAQmx_Val_Volts, None)
  analog_output.CfgSampClkTiming("",outputRate, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, numSamples)
  analog_output.CfgDigEdgeStartTrig("/Dev1/PFI0", DAQmx_Val_Rising)
  analog_output.StartTask()
  analog_output.WriteAnalogF64(numSampsPerChan=numSamples, autoStart=False,timeout=1.0, dataLayout=DAQmx_Val_GroupByChannel, writeArray=data, reserved=None, sampsPerChanWritten=byref(samplesWritten))print("Analog output: Wrote %d samples" % samplesWritten.value)# create digital trigger dig_out = Task()dig_out.CreateDOChan("Dev1/port0", "", DAQmx_Val_ChanForAllLines)
  
  # create digital trigger function
  highSamples = 1000
  numpts = 3 * highSamples
  doData = np.zeros((numpts,), dtype=np.uint32)
  doData[highSamples:2*highSamples] =  2**32 - 1
  
  # send digital trigger
  doSamplesWritten = c_int32()
  dig_out.WriteDigitalU32(numSampsPerChan=numpts, autoStart=True, timeout=1.0, dataLayout=DAQmx_Val_GroupByChannel, writeArray=doData, reserved=None, sampsPerChanWritten=byref(doSamplesWritten))
  print("Digital output: Wrote %d samples" % doSamplesWritten.value)
  

  Hi PatrickR,

  You can review examples of code NI-DAQmx (ANSI C) text based on the production of an output using a trigger to start digital analog. If you included/checked support textual dusing your NI DAQmx driver installation, you can navigate to Windows start > all programs > National Instruments > NI DAQ > Teaxt-Based Code support > ANSI C examples > analog output > generate voltage > Mult Volt updates-Int Clk - Dig start. If you have questions/doubts about the material.

• PCI-6221 PFI0 start trigger is stray signals reading

  We have a card PCI-6221 attached to a SCB-68 in a control console, we've made dozens of times. However, this time, we will have problems with the beginning of PFI0 relaxation. Operation of the actuators 24 v remote (cable to DAQ card but operated through manual switches) triggers the beginning. We tried a shielded cable and everything is grounded. There is no parasitic voltage coming into the SCB-68 box. We sent also all the other analog I/o box. It's just the son of trigger start going. What is unusual, is that if we give a thread to the PFI0 (Terminal 11) who does not finish anywhere, we just hold in the air, do not cross any other thread, running our actuator valves still initiates the trigger. If we remove the wire, it does not raise. It's almost as if she receives wireless signals. But how wireless receives + 5V to trigger I don't understand. We also tried to use a spare PCI-6221, same known issue work. When you view the PFI0 in MAX, flipping the switch actuator will cause the counter generate 400 + charges. A normal release with our power switch usually generate 10-20-count indictment. We are really puzzled. Thanks for any help!

  Don't have not an answer to the first question, will have to research.

  THA Cabinet is wired the same, the only difference is that we added a transformer so that the system can run on the seas, but has not actually been hooked again, sitting in the Cabinet.

  Yes, we used a cable leading to one end. We tried the ground at both ends, the same results. I also waved to the cable in the air and a people in the head with it, it made me feel better.

  Don't think on the unused entries in the Earth. Personally, I think that the PFI0 is to be triggered with less than the + 5V, the scope is the very low voltage reading.

  But I found a solution. I mentioned in the original post that trigger actuator, just once, causing 400 + edge detections/counts when viewing in MAX. It is a large number of charges in such a short time. So I programmed in a digital filter using a min pulse width. ".". 00256. Eliminating the 400 + short bursts of any signal. I used the example of filtering VI in this knowledge base article:

  http://digital.NI.com/public.nsf/3efedde4322fef19862567740067f3cc/9ece7dbe7df338bd86256f8600734a41?O...

  For those who have similar problems, there is no physical change, just incorperate of wiring of the filter.

• 200077 error has occurred to the property trigger Node DAQmx DAQmx Start Trigger (analog Edge.vi:1-> CRT with trigger

  I created a program that reads analog data and draw a waveform, but I need to stop the program when the voltage drops to a certain tension. When I tried the analog edge trigger it showed the error in the subject:

  Reason: The 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: Trig startup type

  Requested value: analog edge

  You can select: Digital Edge, no

  I understand what the analog trigger is not available for my DAQmx version, without again getting equiptment, can I use a trigger to stop reading data at a specific voltage?

  How to start and stop a similar read digital triggering?

  Thanks in advance!

  Ah! Well, then the Boolean value of status would be connected to the State of the thread of the unbundled error, Boolean stop to the stop button and the Boolean value to the right would be the stop for loop itself... so something like this (see image).  This is an excerpt from LabVIEW 2014, so it can not easily fall in your version, but I hope it's clear enough on how you can wire it to the top.

• Start trigger M Series C++

  Hi, I seem to have discovered a bug in my C++ when I tried to delete some maps:

  I usually synchronize each task to a task and THE task is linked to the NISYNC_VAL_PXITRIG0 using DAQmxCfgDigEdgeStartTrig

  Now it worked well as my main task was a S series, but when I was doing my Masters M and acquiring signals series, tasks they never start.

  And Yes, I did some tests on the S series (bind it to a NISYNC_VAL_PXITRIG1 watch it freeze... to make sure that it was indeed listening to the trigger signal)

  Also, if I remove the beginning of NISYNC_VAL_PXITRIG0 relaxation, it works like a charm...

  Finally, each task is linked to the task of master by his "/ AI/StartTrigger ' and it works very well...

  NISYNC_VAL_PXITRIG0 so only is a question... is it because some locations receive the signal sent by the PXI_Trigger or something?
  Should I use the STAR version instead? (With the help of a calendar in slot 2 card)

  Well after trying this Sunday...

  I noticed that all my problems were gone, if instead of linking manually to trigger lines I'd let the frame automatically link as follows:

  (code not real but rather a sketch)

  StartTrigger (taskHandle, "" / Dev1/StartTrigger "")

  and all things HR, I used, I also changed forever the call the trigger lines myself... He solkved that emit a

  Sorry for the long time between response... never got the message that I got a response ^^;

  Thanks if

• Producer consumer Start Trigger

  Short explanation: I use a party apparatus 3rd signal a TTL to use as my trigger early in my VI. My cDAQ and modules seem to have the ability to send a trigger start regardless, but I could not track down the how to do this in a system of producer/consumer.  I have an idea at the bottom of the long explanation.

  Long explanation:

  I am running a test system that monitors the pressure wave by an inflammation of the hydrogen/oxygen. The components are a cDAQ-9188 with modules 9222 (x 3 HAVE broadband), 9481 (x 2 relays), 9402 (x 1 i/o Module), 9221 ('Low' speed HERE).

  Based on the recommendations contained in this forum, I placed my DAQ in a producer/consumer architecture.

  At this point the system works for the most part, I still have some more things to add for all the information I want to collect. However, it records at high speed and the 9221 and the 9222 modules are synchronized. He collected reliable data to date successfully.

  When the system boots it will follow, but not save. I need to fill the structure tested with gas at a specific concentration before I switch on/registration. When I press the record button I have a TTL of the 9402 signal to my high-speed camera and I close a relay on a 9481 who engages in an ignition system. Ignition system takes a variable amount of time to load and shoot so I have a timer that leaves the TTL and the active relay for half a second.

  My problem and it is a small, comes up with the system monitoring and synchronization. In order to get the system to synchronize properly, I had to generate an external impulse in PFI0 to use as a trigger. I tried to assign the different clocks available as a trigger of the beginning, but I found myself with unsynchronized data.

  Is there a way to generate a pulse on my 9402 to use as a trigger? It feels stupid for me to use an external device, when I have something that can generate the signal that I need.

  Thinking about this post, I have solved my problem, at least in my head. I think I can move the output TTL VI (that I'll eventually change to DAQmx) in the loop of producer and move my statements true or false for the consumer in the form of a 1 d array loop in my queue to start recording. Probably more than that, but I can only learn by experimentation on the right?

  Thoughts? Recommendations?

  VI attached.

  You cannot generate a pulse with the 9402 himself. The pulse would be actually generated by the 9188. You must create a task of meter output to generate a pulse train. Try the attached example as a starting point to experiment with the meter.

  This Vi is for LabVIEW 2013, if you have an older version let me know and I'll try to convert.

• DAQmx: set up a digital acquisition continues with start and stop trigger

  Hi all

  I write because I can not find a solution to my problem.

  As written in the title, I just want to do an continuous (continuous sampling) a digital line. The fact that it's a digital line instead of an analog is no big deal, I guess. I want to start the acquisition on a rising edge of digital trigger (PFI0 for example) and stop acquisition on a trigger too (forehead down on the same signal (PFI0 even then) or a new front amount). This way I could precisely control the time of acquisition or of the start or stop other devices.

  Since this is a digital acquisition, you need to do first "something": create a fictitious analog input task and get the clock back to the digital input. I setting this analogue of the task to start on a trigger. It works but I can't find a way to stop it on another trigger.

  Do u hav no idea how to implement it?

  Finally I have not found an easy way to break cautiously the VI to wait for a trigger (in case you want to start an acquisition with different settings for example). Do you use the task to Abort or is it better to set a deadline to playback digital channel VI until the outbreak occurs?

  Any help would be appreciated!

  Thank you

  Config: LV 2010, latest version Daqmx and USB card or 6251.

  Hi Chris,

  One way is to use counters as Kevin described. For me, it's usually easier to create the dummy task that has the timing engine (as I HAVE), but it depends on what resource you have on your board you will not need .

  In fact, the example is the same thing that you need to measure continues - just what you need to do is remove the counter part and replace the trigger reference to be external (your stop trigger).

  with this approach, you should be able to do the continuous measurement - I noticed that you need DI - in fact with few changes you should be able to use this example. DI does not have its own timing engine, that's why you should use the external sample clock. If we use the example to create dummy HAVE to provide the sample clock, and we start DI task until we start to HAVE fake, then we can get pretty much continuous clock which begins start trigger and stop the trigger of reference.

  Take a look in the change - once again, I have not tested, but logic seems to be OK.

  

  with sincere friendships.

  s9ali

• How to delay a PXI-5122 trigger before routed to string of PFI

  Hello world

  I use a PXI-5122 in a PXI chassis. I want to synchronize with two external devices. The first will send a trigger (with a 10 Hz repetition rate) for PXI-5122. Then PXI will generate a trigger (with a constant delay) in the second.

  It seems that I need to generate a trigger, then export this trigger to PFI 0 line, but I do not know how to delay triggers with a timeframe of 4µs. I read that there is a slight delay between a trigger on the PFI and the first sample. And the length of the cable is also an important factor to consider.

  Could someone give me some suggestions?

  Wednesday,

  Thanks for the drawings, that helps a lot!  Somehow, I see this work (how to set up the scanner):

  1. set up the record length to be 12us (4us trigger samples, 8us after outbreak).  If the sampling frequency is 100 ms/s, that would be a record length of 1200 samples.

  2 configure the position of record reference to 33%.  That's how the digitizer breaks 1200 400 samples according to trigger before triggers and 800 samples.

  3. configuration of triggering immediate reference.  This will allow the acquisition of trigger the moment she gained 400 before triggering samples.

  4. export the "reference trigger (Stop)" to send to Device_2.  This output pulse is of variable width, so if you want consistency, you will need to the Device_2 trigger the rising edge of the pulse, did not not fall m.  Once 400-pre-trigger samples are acquired, this impulse will be sent, and then the scanner will be immediately habitable after initiation of sampling.

  5 configure the trigger of the entrance of Device_1 (10 Hz trigger), as the 'Advance trigger' and 'Start Trigger'.  This will make the digitizer wait this impulse to start sampling before the next record.  We set up, the relaxation of beginning to the 1st record and the trigger in advance for all subsequent records.

  This facility should allow a pretty decent timing, but please test to be sure that it will be sufficient for your application.

  Kind regards

  Nathan

• Start-up delay triggers real beginning of the acquisition of waveform on SMU-6535?

  How long does take a condition of trigger start happening to the actual start of the acquisition of waveform on an SMU-6535?  In my case, it takes ~ 70ms, who seems to be too long.  The delay times, I found in the manual are all down in one nano-second two-digit range.

  Here's a little history: I'm trying to measure a PWM signal to report cyclic verity, generation of total time, frequency, etc.

  The PWM signal is entering in the SMU-6535 on line Port3/3, and I rider Port3/Line3 to PFI5 on my map of derivation.  Start trigger is configured to fire on the PFI5 front, with the acquisition of waveform happening on Port3/Line3.  PFI5 and Port3/Line3 consider both the same waveform PWM, which is the yellow signal out of range.

  The task is configured to use a sample of 10 Mhz clock frequency and collect samples of 2 500 000, coming at a time of acquiring signals 250ms.  You can see on the scope probe that there is a gap in the PWM signal.  I want to collect just the first section, and I know that the article is (or should be) long 250ms.

  However, I am very clearly this gap and 70ms ~ the next wave PWM of the PXI system.  PXI signals is checked 250ms.  The problem is that it is delayed by ~ 70ms when the first time PFI5 goes high when it actually starts the acquisition.

  Ignore the ringing.  The probe is not the best reference.

  

  Here's the installation code:

        readPwmTask = new NationalInstruments.DAQmx.Task ("task of reading PWM");
  
        readPwmTask.DIChannels.CreateChannel ("PXI1Slot6, Port3/line 3", ", ChannelLineGrouping.OneChannelForAllLines);
  
  readPwmTask.Triggers.StartTrigger.ConfigureDigitalEdgeTrigger ("/ PXI1Slot6/PFI5", DigitalEdgeStartTriggerEdge.Rising);
  
        readPwmTask.Timing.ConfigureSampleClock ("", 10000000, SampleClockActiveEdge.Rising, SampleQuantityMode.ContinuousSamples);
  Reader = new DigitalSingleChannelReader (readPwmTask. Stream);
  
        drive. SynchronizeCallbacks = true;
  drive. BeginReadWaveform (2500000, New AsyncCallback (DataReady), readPwmTask);

  Narrowed it down.

  This problem only occurs when it is the first acquisition of signals in the life of the application.  If I do a 'normal' acquisition before attempting to use the departure function acquisition, it works much better.

• I'm trying to get my vi to trigger, do not know where to add the trigger

  I need a vi that can trigger using an analog front (1V), then produced a square wave (all square wave will do for now) and then show the extent of the wave.  Attached is the code that I've done so far.  Not sure how to get a trigger attached, or where to put the trigger on what I've done so far.  Another question is where it is triggered since then, I have to add another generating the waveform to produce the trigger signal?

  Any help is appreciated!

  Hello

  You can place a start trigger VI DAQmx in the code above, between the Timing DAQmx and DAQmx write screws and then set the trigger to "Analog Edge" type and specify the channel to trigger of (in this case, I think that you should use the APFI line on your map).  Discover the 'voltage - output continuous' example ' If you need help implementation of this code, this example includes outputs analog with different trigger types in a similar setup to yours.

• Problem sending trigger software through backplane PXI (chassis SMU-1082, SMU-6363 DAQ, SMU-6544-HS-DIO)

  Dear community,

  I am trying to implement a background basket (software) PXI trigger on a chassis NI SMU-1082 with LabView 2015 (32-bit) running on an SMU-8135:

  HS-DIO (SMU-6544) in slot 2,

  -Acquisition of data (SMU-6363) into the Groove 4,

  -Flex RIO (SMU-7962R + OR-6583) in the Groove 3.

  The trigger schema is explained in the attached file ' LV-PXItrig-HSDIO-DAQ - overview.jpg ".

  Scenario 1: written DAQ analog signal and sends signals trigger HS-DIO (software) through bottom of basket, after East of waveform of the complete signals to DAQ for acquisition.

  Scenario 2: logical impulse on an external port HS-DIO triggers signals HS-DIO, after HS-DIO waveform is complete DAQ triggered for the acquisition of the ADC by the backplane.

  In principle this breaks down to send a trigger of module A to B by PXI backplane. The SMU-1082 chassis has a bus trip with 8 lines (PXI_trigX, X = 0,..., 7) more a trigger in Star controlled the slot 2.

  I've linked to implement a software trigger, but I can't access the refreshing resource and execution, see the attachment. Other ways of implementation including the DAQmx Terminal / routine disconnect Terminal have not worked for me either. I am aware about the connection of trigger using the node property VISA but I can't make a trigger.

  Tips, comments or solutions are appreciated. Thank you!

  For scenario 1, you want to trigger the HSDIO acquisition to begin as soon as the analog output DAQ starts?  You can use DAQmx Export Signal to send the trigger for the start of one of the lines from the Trig PXI backplane. Then, you need to configure your HSDIO acquisition to use a trigger digital beginning on the same line of trigger. Take a look at the example of the "Dynamic hardware generation start trigger" in the Finder of the example (help > find examples)

  For scenario 2, looks like you do a dynamic unit HSDIO generation when a digital trigger arrives on one of the PFI lines. Once the build is complete, you want to send a trigger for the DAQ hardware to begin sampling. If this is the case, you again use a trigger to start material in your task of NOR-HSDIO, as you did for scenario 1, but use external trig line as the source, rather than the bottom of basket. There is no case of material when the build is finished, but you can use a marker in script mode event instead. The example of the Generation with dynamic event marker' in the example Finder gives a good starting point for this type of operation. You'll want to set the output terminal for the event to be a line of backplane trig, and then tap the DAQmx to start on the same line trig trigger.

• Measurement of voltage deferred with a start from a pulse TTL (PCI-6251, OR DAQmx)

  Hello

  What I do: gain a measure of tension after a certain period of time (order of microseconds) when we observe a TTL pulse, lasting about 1-100 microseconds. What are the options I to do thins?

  PS. If this problem is solved in a C code example, please point me to the right direction. I saw examples of NOR-DAQmx, but not a not spot something like this.

  Hi hum-human resources management.

  The example of DAQmx ANSI C Analog In\Measure Voltage\Cont Acq - Ext Clk - Dig start shows how to use DAQmxCfgDigEdgeStartTrig() to activate a digital start trigger. It also illustrates the continued acquisition, clock to external sampling and all events of samples N; for a simpler starting point, look at analog In\Measure Voltage\Acq-Int Clk-Anlg start and try to convert to using digital analog INSTEAD of triggers.

  However, this will start acquiring exactly when the trigger occurs, not after a period of time fixed. Use DAQmxSetStartTrigDelay() and DAQmxSetStartTrigDelayUnits() to add a fixed delay between the trigger and the beginning of the acquisition. Help OR-DAQmx C reference (which should be on the start menu under National Instruments > NOR-DAQ) lists the valid values for the property of units.

  Brad

• How to synchronize the start of IT and relaxation the Scan list (DAQmx Switch)

  Hello

  I want to measure samples of N to the AI0 of Council NI PXI 4461. The measurement starts on a rising edge of a digital triggering provided to the PFI0 of the same Board. The measure is configured with samples of N/2 pretrigged. So far, everything is under control...

  Using an NI PXI 2567 Board, the signal applied at the entrance the 4461 (AI0) switches between a V2 and V1 signal. I would like to synchronize the switch between the two signals with the trigger signal applied to the input of the PFI0 Governing Council 4461. In order to obtain samples of N/2 of V1 and V2 samples N/2. Synchronization of 1 to 5 ms would suffice!

  My question is how to synchronize the start of acquisition of AI pretrigged of 4461 with the switch control given by the Council of 2567?

  Thank you in advance for your help...

  PS: the configuration of the system is:

  -LabView 8.5

  -Chassis PXI-1044

  PXI-4461 on slot 2

  Module 4-slot PXI-2567

  Hi Frederic,.

  I came back to this recently and used the following examples to run the desired synchronization.

  PXI-4461: Acq & graph tension-Int Clk - dig Start & Ref .vi

  Samples per channel = 1000

  Rate (Hz) = 10000.00

  Start the trigger Source = / [name of the instrument DAQmx] / PXI_Trig0

  Onboard start = fall

  Reference Source Trigger = DAQmx Device Name] / PXI_Trig0

  Reference edge = fall

  Trigger samples = Variable (100, 500, 900)

  PXI-2567: Switch Scaning-SW Trigger.vi

  Advance the output terminal full = / [name of the instrument DAQmx] / PXI_Trig0

  Scan list = / [name of the instrument DAQmx] / ch0-> com0.

  Scan list = / [name of the instrument DAQmx] / ch1-> com1;

  Hardware configuration:

  The PXI-2567 module controls an external relay that switches between the voltage of 5 V on ch0 and ch1 0 V.

  The PXI-4461 connects to the COM of the external relay and therefore reads 5V when ch0 is connected; 0 v when ch1 is connected.

  Procedure: The above examples are used in the following procedure.

  1. run the PXI-4461 VI.  A start trigger (falling edge) is necessary to start collecting samples before firing.

  2. launch the module, PXI - 2567 VI.  When ch0 is initially (and immediately) on com0, a trigger is sent to PXI_Trig0.  The PXI-4461 will begin to acquire samples before firing.

  3. - click on the "Connect to the next" button on the front of the PXI - 2567 VI module.  This sends a trigger to entry software for the PXI-2567 module and the transitions of the scan for ch1-> com1 list.  Once the PXI-2567 module remains (debounced), advanced complete relaxation is sent on PXI_Trig0 for the PXI-4461.  The PXI-4461 will begin to acquire samples after outbreak.

  Note: Instead of the trigger of the software entry, an external input trigger can be used (e.g. PXI_Trig1).

  Results:

  > Before instant release of samples = 100

  Delay is caused by the time of actuation of external relay.

  

  > Before instant release of samples = 500

  Delay is caused by the time of actuation of external relay.

  

  > Before instant release of samples = 900

  Delay is caused by the time of actuation of external relay.

  

  I hope that the attached screws and the explanation above helps you and/or other customers who have this problem.

  Best regards

  Chad Erickson

  Switch Product Support Engineer

  NOR - USA

• What is the best way to check if the trigger was held

  What is the fastest way to check if the trigger was held. Right now, the only way I can think is to query the number of samples acquired on the AI channel (which is triggered). Is there a faster way? Is there a property node (that I can't find) that returns TRUE/FALSE?

  Thank you

  Can you elaborate a bit more? What type of trip (I guess a start trigger)? What equipment? What do you mean by 'faster '?

  There is no property to "has a start trigger has occurred." If you want to find if a start trigger has occurred, you can he deduct the number of samples. There are several approaches you can take:

  * DAQmx Read will hang until a timeout is hit or up to the number of samples you request is read. You could do a DAQmx Read with a timeout-infinity (1), playback of a single sample.

  * Well, you could ask about properties DAQmx Read TotalSampPerChanAcquired or AvailSampPerChan; Once they no longer means 0, while this NEITHER-DAQmx started buffering data internally, which means that the material received the trigger.

  * If you use a digital border start trigger and according to your material, then you may be able to use the detection of changes in a separate task, but I don't know if it would be significantly faster then the other two approaches.