Software triggered single Pulse Generation

Hi,
I have an AT-MIO-16E10 board and I am trying to generate multiple but
finite digital pulses without having to reset, configure and rearm the
counter for every pulse. This takes too much time for my application. I
would like to configure just once the counter and gate it by any
software method. I am using LabWindows/CVI.
Does anybody know if it is possible to rearm the counter without having
to reset and configure it previously?.
Does anybody know how to generate a software trigger?
Thanks
Manolo

Hi Manuel,
Configure your counter for retriggerable pulse generation, and connect
one of the digital lines to the counter gate. Toggle the digital line each
time you want to generate a pulse. See GPCTR_Set_Application(),
application = ND_REGRIG_PULSE_GNR in the NI-DAQ Function Reference
Manual for details. Please feel free to email me if you need more help.
Regards,
Reed.
Reed Blake
Beta Technology
Industrial and Scientific Computing
Manuel Prieto Mateo wrote in message <[email protected]>...
>Hi,
>I have an AT-MIO-16E10 board and I am trying to generate multiple but
>finite digital pulses without having to reset, configure and rearm the
>counter for every pulse. This takes too much time for
my application. I
>would like to configure just once the counter and gate it by any
>software method. I am using LabWindows/CVI.
>Does anybody know if it is possible to rearm the counter without having
>to reset and configure it previously?.
>Does anybody know how to generate a software trigger?
>
>Thanks
>
>Manolo
>

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Hey 45,
Unfortunately, there is no way to generate a pulse width smaller than 2x your external timebase.
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Monitoring pulse generation

Hi all,
I am using a USB-6210 card and
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\National
Instruments\MeasurementStudioVS2003\VCNET\Examples\DAQmx\Counter\Generate
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\National Instruments\MeasurementStudioVS2003\VCNET\Examples\DAQmx\Counter\Generate Pulse\GenDigPulseTrain_Continuous
\National Instruments\MeasurementStudioVS2003\VCNET\Examples\DAQmx\Counter\CountDigEvents\
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To
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class ?
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Use
a finite pulse train. This imply using my two counters and then i would
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prematurely.
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Duplicate thread:
http://forums.ni.com/ni/board/message?board.id=250&message.id=37363

Synchronous submillisecond pulse generation on 2 outputs

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Hello,
Thank you for contacting National Instruments!
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Attachments:
Generate_Single_Triggered_Pulse_(DAQ-STC).vi ‏104 KB

Two retriggerable pulse generations after a pulse train generation

I am trying to generate 3 pulse trains (ABCABCABC...) one after another.
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pchemjjang,
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National Instruments
Attachments:
Counteroutput.jpg ‏49 KB

Please How can I capture and integrate a single pulse of a DC signal from an external circuit

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I am trying to integrate a signal from an external circuit I have built. I want to capture just a single pulse from the signal and integrate it. Please can anyone assist me with how I can perform this?

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Digital pulse generation

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Right now you are trying to capture a digital signal right?
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Pulse generation from an encoder on a PCI6601

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Hi,
I think you would have to use one counter to count up till x, then you would start the second counter and let it
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regards
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Pulse generation

Hello,
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1 x NI 6537 I/O Card
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I would always start with the example finder, you can teach yourself much daqmx with the axamples alone.
Continious buffered hardware writing will stream out the sequence that you write to the buffer with a hardware timming,
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Software triggering

Dear All,
I'm using LabVIEW 8.0 and Daq-mx to program an application where I use
a finite retriggerable pulse train to time analog output of a waveform.
Currently, I'm using a hardware trigger pulse from another counter to
trigger the pulse train. Is there any way that I can change this to a
software trigger, such that, once I run the program, if I press a
button on the block diagram, it will set off the pulse train and I can
keep on repeating it without having to stop and restart the program?
Anyway help would be greatly appreciated.
Thanks in advance.
-Ashesh
Message Edited by Ashesh on 08-23-2006 01:41 AM

Hi Ashesh,
Thank you for contacting National Instrument's support! That's an interesting question, and I think that you're very close to the solution already. It sounds like you already have the foundation to your program, which will probably be very similar to our shipping example called "Gen Dig Pulse Train-Finite-Retriggerable."
Basically, our counters are only hardware triggered. If you look at the source list for all potential trigger sources, you'll notice that they are all hardware related. Unfortunately, we don't have any software triggers as such.
However, what you could do is use a software trigger to generate a digital high on one of your digital ports, and wire that over externally or internally (depending on your hardware, using the Connect Routes vi. Check in your Measurement and Automation Explorer >> DAQmx Devices >> Device Routes to see what available options you have). You would want to do something similar to the "Write Dig Chan" example program that is also shipped with LabVIEW.
I hope that this points you in the right direction. If you have any questions on implementing this solution, feel free to ask again and I'd be more than happy to help. Thanks for choosing National Instruments!
Regards,
Daniel L.
Applications Engineer
National Instruments

Retriggered single pulse

I am using NI-DAQmx C/C++ API. How can I set up a counter to produce a retriggerable single pulse? That is, I need to trigger an output pulse, and while the pulse is being generated, if a new trigger comes in, it resets the counter so that the pulse timing is extended.
Is that what the DAQmxSetStartTrigRetriggerable property does? I'm guessing that the ability to do this depends on the hardware being used?
Thanks!
John Weeks
WaveMetrics, Inc.
Phone (503) 620-3001
Fax (503) 620-6754
www.wavemetrics.com
Solved!
Go to Solution.

WM_John_Weeks wrote:
I need to trigger an output pulse, and while the pulse is being generated, if a new trigger comes in, it resets the counter so that the pulse timing is extended.
The need is a replacement for the (ancient) NI-DAQ API GPCTR_Set_Aplication() with ND_RETRIG_PULSE_GNR with something equivalent in NI-DAQmx.
I'm glad you clarified. ND_RETRIG_PULSE_GNR does not extend the pulse timing if an additional trigger is received during generation. From the NI-DAQ Function Reference Manual:
ND_RETRIG_PULSE_GNR: ... Any gate transitions received during the pulse generation are ignored.
With this in mind, DAQmxSetStartTrigRetriggerable is in fact what you would want to use to get the same behavior in DAQmx.
Best Regards,
John Passiak

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