PCI 6251 ConfigureAnalogEdgeTrigger
Hello,
I try to start a measurement on a analog signal. This signal is a positive pulse. When it arrives, i start to count until the signal on "ctr0" arrives.
So i try to configure a analogTrigger on APFI0. But the following error occurs :
"Specified property is not supported by the device or is not applicable to the task
Property : CNiDAQmxStartTrigger::type
Task Name : BancDeTest
Status Code : -200452
Any one can help me ?
Thank you.
I've attached two files
Attachments:
DAQmxTaskTempsDetection.cpp 6 KB
DAQmxTaskTempsDetection.h 7 KB
Hi everybody,
This is a tricky one so I just wanted to post so there isn't any confusion here. What you have described would not be possible on any of our Multiplexed boards. It is a bit difficult to find, but page 11-3 of the M Series User Manual actually mentions the restriction:
When you use an analog reference or pause trigger, and the analog channel is the source of the trigger, there can be only one channel in the channel list.
We can explain the restriction by looking at the triggering circuitry (page 11-2 of M Series User Manual):
When using a reference trigger, the hardware is actively sampling data the entire time in order to create a pre-trigger buffer (i.e. the data is being MUX'ed into the ADC). The routing of the ai channels to the triggering circuitry is after the multiplexer. So, we have the multiplexed version of the ai lines going into the triggering circuitry MUX. We do not allow the user to configure an AI line to be used for a reference trigger in this case since there is no way to isolate the single AI line to be fed into the triggering circuitry (e.g. we might trigger on a transition between ai channels even though both lines are DC signals).
The best workaround use the APFI lines as your trigger source. Looking at the above image, they do not have the same restrictions as the AI input lines when used for Analog triggering since they may be directly rotued to the triggering circuitry.
If you have any questions about this don't hesitate to post back!
Best Regards,
John Passiak
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modified code.png 18 KB
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Buen día:
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Preguntas:
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¿Existe algun ejemplo para estudiar su implementación?
Cuento con LabVIEW 8.0 y tengo instalado el modulo Real-Time.
Tengo algunos problemas con el tutorial Real-Time.
Gracias de antemano.Estimado itlcarlos
Gracias por utilizar los foros de National Instruments.
En primera instancia quisiera entender a lo que te refieres con "Tiempo real", ya que tiempo real indica que estarías trabajando bajo un sistema operativo determinístico con el cual te asegurarías que existe confiabilidad total en el sistema, de ser así no podrías trabajar en Windows ya que no es determinístico. Si intentas ver la tarjeta como un dispositivo RT no va a ser esto posible en el proyecto de LabVIEW.
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Me gustaría me aclararas si esa era tu pregunta o me detalles un poco más que es lo que intentas hacer y con todo gusto te ayudaré.
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Que tengas un excelente día.
NI 625x Specifications
http://www.ni.com/pdf/manuals/371291h.pdf
Coamín Cruz
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The PCIe-6259 is a x1 lane PCI express board. Basicly, the driver software is the same for both boards (DAQmx) and programming is not different for these boards. Yes, a BNC-2110 can be used allong with this board. Last, this board should be orderable in the Neterlands without any problems. For more order information you could contact the dutch office and ask for the sales department.
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Rik Prins, CLD
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Please tip your answer providers with kudos.
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Hello
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We have PCI-6251 card for voltage acquisition at 200 sample/sec at 14bit. Now I see NI has new product for wi-fi wireless measurement. I see WLS-9219 (4-channel, 100 S/s/ch, 24-bit, ±60 V, ±25 mA universal input) may meet my requirement. But I am now sure and want ask NI expert, Does WLS-9219 can transfer 200S/sec at 14 bit???
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LimingHey Liming,
The 9219 does not have a flexible resolution and the max sampling rate is 100 S/s/ch. You will not be able to achieve 200 S/s/ch with this device.
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National Instruments -
Hi all,
I am using DAQ PCI6251. Can I use this card for creating PI controller ?
Basically, I think that we can analyze a PI controller into two phases, including the proportional and integral phases. I could do this easily with Labview library. But I am facing a difficulty how to build the saturation block for PI controller ?
Pls give me the solution.
Thanks so much for your helps and supports.
Best regards,
DuyDear Jochen,
Thank you very much for your reply.
I can describe what I am doing as follows:
I would like to control the induction motor drive system with vector control approach.
The equipments in my system include the induction motor drive system, inverter, PCI 6251 Labview card, block connector BNC2110. I am using Labview 7.1.
I will gather the stator currents and voltages from the induction motor under analog signals. Then I will make some calculations on Labview with available Labview library. After that I will output two analog signals. PCI 6251 has two analog signals. I will use two analog signals from PCI6251 Labview card as input signals for PWM generating board which I could bulid. This PWM generating board will create signals to trigger IGBTs of inverter. And the inverter will create signals to control the induction motor drive system.
In this drive system, we need to use two PI controller as the requirement of vector control approach.
I hope that my description is clear.
The expected sample rate is 10 kHz.
I am using XP Window OS.
I attach the diagram what I need to do as well.
Thanks so much for your great ideas.
Best regards,
Duy
Attachments:
Practical_diagram_Labview_NI.pdf 27 KB
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