trigger 6132 from 6602

[klausc127]

Hello,
I have the following task:
In my system I am counting quadrature-encoder on the 6602-board. I need to trigger analog-data-sampling on the 6132 at a certain value of the counter and then sample at 3 Mhz. The time between the arriving at the position (counter-value) and the start of the sampling should be as low as possible (zero?), at least it should be stable at very small value, so there should be something like a hardware-trigger.
Is this possible? Are there examples or other documents.
Sorry if this a stupid question
and thank you for any hint.

Klaus

[Christian Mergl]

Hi Klaus,

What you will need is to build a pulsetrain generation on the counter card (6602) and use the generated pulse train as start trigger on your dataacquistion board (6132)!

For the pulse train generation you take the quadrature encoder signal as timebase and configure the low time of the pulse train with the number of samples, so the value of pulses from the quadrature encoder which should perform the start of the acquisition. E.g. after 5000 pulses you will receive a rising edge. This rising edge you can use as start trigger for your acquisition. You can hardwire the counter output from the pulse train generation to a PFI of the 6132 (e.g. 6602\ctr1_out to 6132\PFI0) , or via RTSI cable (better) if you are using PCI-Cards, or via the integreted RTSI if you are using PXI-Cards.

For more information about pulse train generation or analog input with external trigger please investigate the DAQmx example libraries or the DAQmx help!

BR, Christian