synchronize AO and AI

[NIDAQ user]

Hello,

How do I program a two-channel AO that is exactly in sync with a two-channel AI (using NIDAQ 6.9 within Visual Basic)?

I thought it should be enough to just trigger both AO and AI off the same pulse, since both derive their update/convert pulses from the common master clock - but it turns out that usually either AO or AI runs a bit faster than the other than this way.

I had also tried the approch by deriving the AI convert signal from the AO update pulses by using the PF5 line - but without success.

I am using a PCI-MIO-16E4 or alternatively a PCI-6110 board.

Any ideas?

Thank you,

Tilman

[Andre_Saller]

Hello Tilman,

so that AO and AI work synchronized, it is not enough to just trigger them simultaneous, you have to synchronize the clocks additionally.
Because I don´t know if you are using the ActiveX components or calls to the nidaq32.dll directly to program your application, I can not tell you how this is done in detail. In the ActiveX elements you can select the clock source directly in the property-page of the activeX elements. If you are using the dll, you have to route the signals with the function Select_Signal. You can check the NI-DAQ documentation for more details.

[Kai I. H.]

Hi NIDAQ user,

i've got a question: How did you trigger both AO and AI off the same pulse so that analog input and output can run simultaneously?

I have to run analog input and output simultaneously and it doesn't work in my application...

Hope you can help me!

Thanks in advance.

Kai

Message Edited by Kai I. H. on 07-26-2005 01:20 AM

[Andre_Saller]

Here you can find a link on how to do this:

http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B45EACE3E9D356A4E034080020E74861&p_node=201234

[Kai I. H.]

Is there also a VisualC example because I'm using C++?

[Andre_Saller]

Here is an example in AnsiC that uses DAQmx, that might help you:

http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=EE91CE2098BB42C1E0340003BA230ECF&p_node=201206&p_source=External

In general you can search for examples on your own in the developer zone.

[Kai I. H.]

Thank you for you help. Next time I will have a look on my own.