NI PCI 6731 with DASYLab

[MD_Electronic2]

Hello Dasylabers,

I use a NI PCI 6731 to do waveform generation with DASYLab 11, which works correctly.

But this card is able to have an external reference signal (AO EXT REF) for the digital to analog converter.

How is it possible to active this function for each converter (there is 4) in MAX or DASYLab?

Thank you in advance for your help!

[MHa]

Hello Frédéric,

we would like check if it's possible to configure this feature into a MAX NI-DAQmx task. I contact you later.

Best regards,

MHa

[MD_Electronic2]

Hello MHa,

Thank you for looking at a solution.

I have not seem the possibility to choose external ref in Max.

I only found this information in Max Help:

Devices that support an external voltage reference enable you to maximize the resolution of your device. If you know that the voltages you wish to generate will never exceed a certain level and you can supply an external reference voltage at that level, you will achieve the maximum resolution your device is able to provide. The external reference voltage settings are available as a Channel attribute/property in the Analog Output»General Properties»DAC»Reference Voltage.

The problem is to change this attribute/property in Max or Dasylab!?

[MHa]

Hello Frédéric,

sorry I have not yet more details for the specific 6731 device feature configuration under MAX NI-DAQmx configurator. But general - We support under DASYLab NI-DAQmx driver only properties:

- which are supported and can be configure from MAX NI-DAQmx configurator itself
- Channel attribute/property (available under LabVIEW) are not available / changeable under DASYLab

Best regards,
MHa

[MD_Electronic2]

Hello Mathias,

Bad news! It could be interesting, in the future, to have possibility to change channel attribute/properties under Dasylab like we can do pfi routing for clocks!

Today I can choose external clock, but not external analog output reference...

I have an idea for this problem, but I'm not shure it works: I could use Labview to modify the channel attribute/ property of the NidaqMX task created with MAX and replace it, so Dasylab could import this modified task with the right channel/attribute property!

What is your mind????

Frédéric

[MHa]

Hello Frédéric,

your idea to modify an under MAX already defined NI-DAQmx task - it's a good idea - we use this way already with our current DASYLab 9.x ... 11.x NI-DAQmx driver interface. So we "ask" with the NI-DAQmx API functions for all under MAX defined tasks and get return for every task a specific handle. We change now under DASYLab some parameters from a task, for instance the analog input sampling rate, blocksize, ... -> but only some little things. General we can only handle parameters which are already defined into the NI-DAQmx task from MAX itself. This changes are temporary and not saved into the task database from MAX - This is not supported from NI-DAQmx API.

Your idea to modify the MAX task under LabVIEW: I'm also unshure if this way is a workarround. I'm affraid that DASYLab and LabView work with another "copy" handle from task pool - same data task base, but different instances with DASYLab tasks handle and LabVIEW task handle. So I'm unshure if the relation         LabVIEW <-> MAX task <-> DASYLab
works for this workarround. I think the more useful way is if you contact the NI-DAQmx developers with your application request to implement this feature direct into the NI-DAQmx task configurator.

Best regards,

MHa

[MD_Electronic2]

Hello Mathias,

I've tried to modify with Labview a MAX task and save it. I have this result:

Not modified MAX task:

Task modified with Labview and saved in MAX:

It seems to work, but I have not the hardware to test the result in Dasylab. I use simulated hardware.

Sure that this possibility should be add in MAX task configurator, so Dasylab could use all the hardware functions!

How can I contact NI-DAQmx developers?

Where are the ressources for NI-DAQmx API functions?

Thank you for your help,

[MHa · Accepted solution]

Hello Frédéric,

"... How can I contact NI-DAQmx developers? ..." - I make an arrangement for you and get in touch via E-Mail.

"... Where are the ressources for NI-DAQmx API functions? ..." - NI-DAQmx -> https://www.ni.com/en/support/downloads/drivers/download.ni-daq-mx.html

Best regards,
MHa

[MD_Electronic2]

Hello Mathias,

Thank you for the information and the contact. I hope they could do somethink!

Meanwhile, there is a solution: I have a Labview program that drive the DAC (in pooling mode) and the values are send by Dasylab using datasocket.

Not vey fast and reliable, but it works.

Should be better if Dasylab Datasocket Module was supporting all the Datasoket functions, but it's not done...

Perhaps in Dasylab 12?