Use DIO and counter in DIAdem

[somewei]

Dear,

I can successfully execute a AI and AO task using DIAdem DAC and my DAQ device. But when I try a DI task and counter input (for frequency measurement) task, problem occur, every time I start the DAC module, nothing happen but a short twinkle, it stops immediately before there is any measurement data. The DI and counter input virtual channels work fine in DAQmx, and I can see them in DIAdem. Did I miss something ?

Regards 

Somewei

[ralfn]

Hello somewei,

I tested it here successfully with the following settings:

MAX:

 Data Neighborhood
 - 1 global virtual channel for DI (port)
 - 1 global virtual channel for CI (frequency measurement)
 
 see attached images (MAX_01 & MAX_02)

 NOTE: Ensure for this test that there are only these two global virtual channels in MAX.


DIAdem (*):

 clock-block
 - clock: DAC-core->software clock
 - sample-rate: 100 Hz

 (DIAdem_clock-block)

 clock-source should be Windows-Timing (Settings->single value processing->measurement parameters->timing source)

 (DIAdem_timing-settings)

NIDAQ-block
 - add the two signals to the MAX signal list (e.g. MyDigitalInChannel_Port & MyFrequencyChannel)
 (DIAdem_NIDAQ-block)


Please test it in the above configuration.


If this shouldn't work please provide me with
 - the DAC-card you're using
 - the version of DIAdem
 - the version of the DAQmx-driver
 - the version of the operating system (any servicepack?)


Good Luck !!!

With best regards,
RalfN

(*) I have only a German DIAdem version here. So terms may vary.

[ralfn · Accepted solution]

... remaining images

[somewei]

Hi Ralfn,

Follow your instruction, I succeed also. Change the timing selection from 'set best timing automatically' to 'set windows timing' make the difference. Thanks so much.

A further question, how to use hardware trigger function in DIAdem ? 

DIAdem 9.10 with DAC bundle

Windows XP

NI USB-6211

MAX 4.5.0f0

Best regards

Somewei

Message Edited by somewei on 09-30-2009 12:16 AM

[ralfn]

Hello somewei,

traditional hardware-triggering is not supported, but in almost all cases it's not necessary.

For triggering-purposes you typically use the advanced triggering-functions of DIAdem DAC. They can be found under control (gear-icon). 

You can choose between a slope-, a window- or a a signal-change-trigger.

For a digital-trigger use a NI-DAQ-block (DI-line) and connect it to the slope-trigger-block.

With the output of all trigger-blocks you initiate an action, e.g. you can start or stop a measurement (via the control-inputs of the save-block).

I hope this helps. 

With best regards, 

Ralf N.

Message Edited by ralfn on 10-02-2009 04:14 PM

[somewei]

Hi Ralfn,

This method come into my mind once. It seems here we monitor signal change of the trigger source and response to it by DIAdem at Windows level, is it the same as Labview? I thought in Labview it is those chips in DAQ device that monitor the trigger source and response to its signal change.

Best regards

Somewei 

[EricHayoz]

Another solution for frequency measurements or triggering functionality is my example program (which can be even used with non-NI devices):

Frequency Measurements and Triggering with DIAdem DAC - Discussion Forums - National Instruments

https://forums.ni.com/t5/Example-Program-Drafts/Frequency-Measurements-and-Triggering-with-DIAdem-DA...