05-19-2007 03:49 PM
Hi,
I am trying to utilize a feature detailed in the NI tutorial Triggering With NI-VXI of the TIC ASIC within the NI GPIB/VXI controller in my application. I am trying to generate a simple SYNC trigger (low going pulse) on VXI TTL0, map that trigger to the External connector of the GPIB/VXI (GPIO1) with signal conditioning, specifically - stretch the trigger pulse to one clock cycle Synchronously based on the clock signal applied to the EXT clock input (GPIO 3). I have managed to generate the trigger on VXI TTL0 and map it to GPIO1 with the following string commands:
"MapTrigTrig 0, 41, #b0000;*WAI;SrcTrig 0, 4, 0"
The following command which is supposed to use the EXT Clock behaves identically to the last... I'm not sure it did anything...
"MapTrigTrig 0, 41, #b1000;*WAI;SrcTrig 0, 4, 0"
When I try to tell it to synchronize with the external clock:
"MapTrigTrig 0, 41, #b1001;*WAI;SrcTrig 0, 4, 0"
I lose the trigger mapping all together... It is still on the backplane, but not coming out of GPIO1
And when I try to tell it to do everything I want, Map it to GPIO1, Use External Clock, Sync with Edge of Clock, and Stretch to one Cycle min:
"MapTrigTrig 0, 41, #b1101;*WAI;SrcTrig 0, 4, 0"
I still get nothing out of the mapping, but sourcing the backplane is still working...
Any help with this would be greatly appreciated.
Thank You, Stephen.