Is it possible to use master slave independently?

[vjuno]

Hi,

 I have to PCI 6120 cards installed on my computer. Currently we have a program that acquires data from both the cards (one being master and other being slave). Is it possible to acquire data independently from the two cards without getting the bridge cable out of the cards? Or will that effect the data acquired from two cards?

Thank you in anticipation. 

Vijay 

[Jordan F]

Hi Vijay,

I take it that you are currently synchronizing your two PCI-6120 cards for acquisition by using master/slave architecture or by having the analog inputs all in the same task.  Are you asking about how to run them independently to acquire data and if that will affect your application?  If so, i do not see any problem with running the cards independently in your system with different sample clocks.  However, I am not sure the details of what you are doing in your program currently, what kind of signals you are measuring, or the overall application.   

Message Edited by Jordan F on 04-16-2009 05:25 PM

[vjuno]

hello Jordan,

Thank you for the reply. Yeah, currently we are synchronizing the two cards.  Ad now I wish to collect data from the two cards independently (with two different programs). Intially we were collecting data at the rate of 1MHz from 6 channels (3 on each card). But we see certain problems while handeling that much data. We are measuring voltage from each channel. This is how our code runs:

We collect voltage signals from 6 channels (3 on each card) , plot it on graphs and is temporarily stored into an arraylist. Once we are done collecting data, we write the data to to different files (one for each card). But, now our experiments demands for collecting data separately. I just wanted to ask if I can do that without having to make any alteration in the hardware and without the two card interfering with each other while data acquisition.

Once again thank you for your time and patience.

Vijay 

[Jordan F]

You do not need to make any hardware changes when running the cards independently (such as removing the RTSI cable, etc.).  All you have to do is in software set up each card to use its onboard clock and you can run them separately at different rates and they will not interfere with each other.  You will still have the same limitations though of transferring data across the PCI bus as you did when the boards were synchronized.