Motion Control and Motor Drives

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How to get time based external encoder position.

I have a servo linear motion system with 7344 and PCI6024. I run a
onboard program in a loop while i measure force and sound with AI on
6024 triggered by RTSI0 line from the onboard program each time a new
move is started and samples are syncronized (rate = 20kHz) by a
counter. I use continuous sampling because i don't no the time one
move takes.

Question 1.
I want to show data for one move, but at the same time don't loose any
samples from the second move and so on. How can i get the excact time
the next start or stop trigger arrives and continue sampling? (See
drawing) The closest i get now is to stop sampling before next trigger
arrives so i am ready to start a new sampling on trigger. I use DAQmx.

Question 2.
I have
a second incremental encoder to collect time based position
from the move. Rate = min. 500samples/sec. Software read is not
accurate enough, so i have to do it with hardware. The encoder is
connected to encoder 2 input in 7344. How to reach this position
syncronized with the earlier mentioned measurement? Do i have to
connect it to the second counter on 6024 to get it syncronized? What
is the best methode?
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To retain data during each move, you may consider using high speed capture, such as demonstrated in the following example:
Developer Zone Example: Onboard Program - Continuous High Speed Capture into General Purpose Buffer

You might also find the following resources helpful:
Developer Zone Example: Motion Synchronization with DAQ via RTSI (Routing Onboard Breakpoints to DAQ...

Developer Zone Tutorial: Integration with Motion Using RTSI
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Message 2 of 2