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Triigering two cards from one trigger

Here is a quick question - in the diagram below it shows two cards (DEV1 and DEV2) being triggered from the same device (DEV1).
 
 
The way I understand LabVIEW is that once it is setup and sitting waiting for the trigger it becomes indpenedant of sofwtare making it more accurate in time. That is fine for DEV1 using a DEV1 trigger, what happens if DEV2 is using a DEV1 trigger does it incur a time cost does it use software in order to begin acquiring ADC data.
 
I suppose to summarise what I am asking is,
 
(1) If I wired the trigger into one device and then on my VI made both devices look at that trigger will it be less accurate than if I (2) phyiscally wired the same trigger to both DEV1 and DEV2 via a SCB-68  and then in the VI made them look at their own device trigger. Is (2) more accurate because I am using both the cards hardware to begin data acquisition and in (1) I have one card which is relying on sofwtare to tell it tha something is triggered. If this is a case is it really an issue anyway, i mean is do I really incur large error in timing (a 1ms is bad timing in my case)?
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For shared card triggering the RTSI bus cable is a nice option.

 

Paul

Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA
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Hello Mr Nice,
 
Using a RTSI cable between your devices will be the way to go to achieve what you wish. Theres a great article on the NI DeveloperZone that discusses the different possiblities of Multifunction and Multidevice triggering and synchronisation, you can read it here: M Series Synchronization with LabVIEW and NI-DAQmx
 
Hope this helps Smiley Wink

Tom
NIUK
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