Triggered signal = digital output

Hello everyone,
I am using the following:
NI6220(PCI, M-series)
Visual Studio 2003 C#
The project I am working uses a watchdog. I get a serial signal which I have to pass on. I was thinking of a trigger to read this serial signal, and then pass it directly on by using a digital output. At moment I read the serial signal with a pausetrigger which starts a pulsgenerator when it is high and pauses the generation when it is low. This is not what I want, because in this situation you are working with a predefined pulstrain generator(initialization of frequency, duty cycle et cetera). While the serial signal is randomly high an low I cannot use this predefined signal. Is there an other way to get this working.
Can anyone please help me with this problem.
Thanks in advance,
Souza

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Externally Triggered 6534E Digital Output

Hi Dear Friends,
I have get a question on how to do the triggered output for the 6534E card. Right now I am using the 6534E card to output a digital gate pulse, and I want to synchronize the output of this gate pulse to an external source, which is the Sync output of a Angilent 33220A function generator(10 kHz). I want the rising edge of one trigger pulse(the sync output) to start one digital gate pulse output, and when one digital gate pulse if finished it waits for another rising edge of the trigger pulse to start another digital gate pulse.
For the more detailed description, please have a look at the attached waveform. Hope you can shed some light on the possibility of doing this.
Thanks a lot for the help.
Attachments:
6534 Triggered Digital Output.JPG ‏95 KB

Hello tiddlycorona,
From the diagram you provided, you can try the Gen Dig Pulse-Retriggerable.vi. This LabVIEW example demonstrates how to generate a digital pulse from a Counter Output Channel on a digital trigger. The Initial Delay, High Time, Low Time, and Idle State are all configurable. It also shows how to use a Digital Start trigger, so the digital pulse is not started until a trigger signal is received. Though the pulse is configured in terms of ticks, it can easily be modified to generate a pulse in terms of Frequency/Duty Cycle or Time.
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Ali M
Applications Engineer
National Instruments
www.ni.com/support

MyDAQ, Increase Digital Output?

Hi y'all,
I'm currently working with a myDAQ trying to trigger three 3V relays through the digital outputs. My main problem is instead of giving me 5V when triggered, the digital outputs are only giving me ~2V since they can turn on an LED, but they don't switch my relays. Is there any way to increase the voltage coming from the digital outputs?
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Hello SNorrell,
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How can i generate an output pulse at every 10 input pulses comming from an encoder?
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Hello jyp777,
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I am a beginner in Labview and would appreciate any advice on how to solve the following problem.
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Solved!
Go to Solution.

Hi Yann,
Wow, thank you so much for this example! I'm trying to take a look at it, but when I run it.. it responds with the following error message
Error -200452 occurred at Property Node DAQmx Trigger (arg 1) in DAQmx Start Trigger (Digital Edge).vi:1->reprise-1.vi
Possible reason(s):
Measurements: Specified property is not supported by the device or is not applicable to the task.
Property: Start.TrigType
Task Name: _unnamedTask<49>
This is strange too, because ive already used the Digital Edge Start trigger for a different application with this card.
-Sidney
NI Hardware: PXI-7853R, PCI-5122, PCI-6733, PXI-1036, PCI-MIO-16E-4, PCI-6110
Computer Hardware: Xeon Quad Core - 2.33 Ghz, 8 GB RAM
Software: Labview 2009, Labview FPGA 2009, Vista 64-bit, MAX 4.6, DAQmx 9.0, NI-SCOPE 3.5

How to do a digital output triggered by the falling edge of a clock?

Hello !
I would like to do a digital output (on a given line of a pci 6602 card) triggered by the falling edge of a clock.
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see the following link (other forum same subject)
http://forums.ni.com/ni/board/message?board.id=40&message.id=1634

Is it save to use digital output as a digital input signal for another channel

Hi all,
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I do loop backs all the time, especially in my test systems as a way of making sure my signal is making it to the UUT pin. I typically throw in a 10k resistor just in case, but I have never had an issue.
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SB X-FI Titanium.. Digital output works but Analog Signal M.I.A.

@SB X-FI Titanium.. Digital output works but Analog Signal M. I.A. Hi Guys,
I recently installed a new hard dri've on my machine after my power supply failed and fried it. After reinstaling Vista 64 and my drivers I noticed that my sound card was not working properly.
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DRe: SB X-FI Titanium.. Digital output works but Analog Signal M. I.A. High definition audio device is what your card is detected as until you install the original CD driver or the Daniel K 2.0 support pack. Then you can update to the newest Creative drivers. I tried to format just like you and thought that I would just download Creative's newest driver and start from there. No Go!!? The newest Creative driver seems to install, but then after reboot like you, I have multimedia audio device.
So take out your CD if you have it, and run the driver setup only. Then using just this driver you can install all of the newer Creative updates. The Creative auto updater is installed along with your original driver and you will see it detect all available updates.
Easiest solution of all,
Try this pack and save yourself a load of hassle........
http://forums.creative.com/t5/Sound-Blaster/SB-X-Fi-Series-Support-Pack-2-0-05-5-2009/td-p/527485
This will install a very proper Creative driver, and applications that will work very very well on your system compared to the CD orignals

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Any advice appreciated / Martin
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Even with an onboard program you will always get a delay of several milliseconds between your axis has crossed the position and until the digital outputs are set. If this is ok for you then you could choose this approach.
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Digital stimulus-frequency response: Need to drive with digital output trigger. Using counters for response.

I need to drive stimulus-response with a software driven digital trigger and NI-TIO counter based response. No analog I/O is really relevant, although I have a PCI-6035E multi-function DAQ as part of my gear. I intend to use the analog, but its timing is non-critical and can be software timed.
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What I need is:
while( enabled )
Repeat at (
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Post-process
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I have made some failed attempts which relied on software to sync up the trigger and the response frequency acquisition. This is definately flawed. I need to start the counting right after setting the digital output trigger, and stop the count after a fixed interval for frequency calculation.
I am having trouble working through the signal routing to get the timing to trigger off the digital stimulus output pulse.
Any help would be appreciated
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Joe

Joe
What are you using the trigger from the 6035E for? I do not know what you mean by, "to trigger frequency countes."
If you are having problems just routing the signal to the 6602, here is a vi that shows you how to route a signal through the RTSI cable to use as the source of a counter.
Brian
Attachments:
Route_RTSI_to_Source.vi ‏67 KB

Need 1200 digital outputs that can be updated at 1 MHz

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Thanks for your response.
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Sequential Digital Outputs or Counters

I am trying to sequentially flash four digital outputs. I want to run them at a frequency, with 25% duty cycle, one after the other. To be clear, output one on for 25%, output two for 25-50%, output three for 50-75%, output four 75-100%, then repeat. I tried using four counters, but they are not synchronized, so the pulses do not stay sequential. I am using a USB-6143. This seems really basic, but I am a pretty new user.
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Assuming you are using the USB-6343 (there is no USB-6143, although there is a PCI variant), you can either run 4 counter output tasks with triggering and appropriate initial delays, or you can use a single digital output task with the appropriate waveform--for example, using lines 0:3 you could generate {1, 2, 4, 8, 1, 2, 4, 8 ...} to get the desired waveform. The frequency of each output would be 1/4 of your sample rate (the sample rate is configurable).
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Duplicate digital output on 32-bit port

Hi all, any help appreciated with the last (!) step in a very time consuming puzzle...
I have a PCI-6254 card with 2 x 64 channel breakout cables. Each cable goes to a remote box, each of which essentially runs a multiplexer and acquires analog signals.
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Thanks!

Thanks both, really appreciate your input. I think I tried something like that today with no success but maybe I did it wrong. It ran without errors but just generated the output on 0:3. I'll try your suggestion in the morning (New Zealand evening now).
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Trigger Solenoid Valve (Digital Output)

I was wondering wether it is possible to use a trigger to send a signal to a digital output. I currently have to send a signal to a solenoid valve when the slope of the data I am acquiring starts to become negative. I know LabVIEW can do triggered data acquisition but can it send a signal to a digital output based on a trigger (falling edge)? I already know what code the signal should send. However, i tried trigger.vi without success. I am relatively new to LabVIEW and would really appreciate any help.
Attachments:
Moses_SBE_SSE_Triggered_Continuous_Acquisition.vi ‏76 KB

Hi M^2,
If all your trying to do is a software timed trigger as shown in the vi that
you provided, theres a few things that I would change. First off, I would
create the digital output channel and start it prior to the loop. Second,
I would initialize the value of the digital output to high (I was using an
inverse logic LED output) prior to the loop. Then after the trigger is
found, write the digital output to the opposite (low). In addition, I
changed the DAQmx read to 1 channel with N samples (1D DBL). This seemed
more appropriate if you’re just using one analog input channel.
I've gone ahead and uploaded the code I modified. This is setup to my
parameters. Basically, I triggered when my thermocouple voltage rising
edge went over 0.29V. You will need to change these settings back to what
you need for your application. Also, I wanted to note that once the
digital output is changed low when the trigger is found it will remain low
until changed high again.
I hope this helps,
Paul C.
Message Edited by Paul C. on 08-16-2007 03:34 PM
Attachments:
Moses_SBE_SSE_Triggered_Continuous_Acquisition (REVISED).vi ‏81 KB

Solution to my Audigy 4 Digital Output probs... please make a stic

I was recently playing Q3TA with my son when my overheat protection kicked in. I exited to windows to see the temp and throttle back my CPU a tad, and when I returned I had no sound from my digital output. Analog was working fine, however.
Setup:
Giga-byte GA-MA78GM-S2H w/780g chipset
Athlon 64 X2 5000+ BE
Integrated Realtek HD audio (disabled)
Integrated ATI HD 3200
2xGB 800MHZ DDR2
Creative Audigy 4
Boston acoustics Digital BA735 2. speakers
I went over every setting in all of my consoles, HQ's and drivers. I played with driver versions, DirectX versions, diagnostic programs and procedures in the knowledge base. In defeat, I even wiped out my XP install and started fresh with the Aud-4 removed, using analog on the integrated card thru headphones. Then I disabled the integrated card and reinstalled the Audigy 4 only to find that there was still no sound from the digital speakers.
Solution?
I[color="#ff0000"] unplugged the power to my speakers, and reconnected everything. As soon as the power was back up, the sound started playing (I had a .MP3 on for testing).
This stumped me for two reasons that occur to me know:
. These speakers (and possibly many others) don't fully power down when you turn the volume knob off and the light on the satellites goes out. The decoder and subwoofer unit keep their light on.
2. Apparently, some situations introduce a faulty signal to the digital output that scrambles the speaker units and they refuse to operate any longer.
Now I know, unplug the power to my speakers. My system works on all three sampling frequencies in "audio console" 44., 48, and 96KHz. None of the troubleshooting procedures touched my problem, because they didn't even mention the speaker setup, let alone doing a hard reset.
Please please please!
Make this a sticky for future me!!!

The Digital output jack on the card isn't of optical signal type.....you will need to get those I/O module mention bt johnston2 for optical connection.

Triggered signal = digital output

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