02-09-2015 03:10 AM
Hello,
When setting up niSync Connect Software Trigger.vi, I get the choice of 8 PXI_TrigN trigger lines (see screenshot). However, for a multisegment chassis like the PXIe-1085, there are 3 x 8 = 24 PXI_TrigN trigger lines, where each segment has 8 lines.
From some quick testing, it looks like the software trigger connects to the middle segment. I'm just wondering if it's possible to connect directly to the other segments?
(This is simply for academic curiosity -- for my real application, I think I'll use the Star Trigger to reach all segments simultaneously)
Thanks!
02-11-2015 11:58 AM
Hi,
You can route trigger lines across multiple segments. Click on the following KB for more details:
Routing PXI Trigger Lines Across the Buses of Multisegment PXI Chassis
http://digital.ni.com/public.nsf/allkb/CA9A49FA50393C4186256DC200774E2B
By the way...
If you have have a PXIe-6674T and do use the PXI_Star lines, you may want to route the Global Software Trigger to an intermediate terminal before fanning it out to the PXI_Star lines. This will ensure the trigger reaches each slot at the same time. If routed directly to the PXI_Star lines, the software trigger may be delayed by one synchronization clock cycle to some slots and not to others. The following example demonstrates the use of PXI_Trig0 as a intermediate terminal:
You can also use a PFI terminal as an intermediate terminal.
Depending on your application, the delay might not be an issue. By default, the synchronization clock is PXI_Clk10 which runs at 10MHz. With this clock you might see a 100ns delay between PXI_Star lines when routing the Global Software Trigger directly to them.
Regards,
-Tyler