How to sync. 50Hz sample rate with 5Hz external digital trigger signal?

Hello there,
I want to sample an analog input at 50Hz, where I further want to use
the 5Hz PPS signal of a GPS receiver as an external trigger/clock
signal for the NI DAQ USB-6008 device. However, I do not want to read
10 samples every 200ms (= 50Hz avg. sample rate), but I want to read 1
sample every 20ms, i.e. with "real" 50Hz.
The "natural" way, it seems would be to use a task that waits for a
rising edge on the ext. trigger input, then reads 10 samples, then
waits for the next trigger edge, and so on.
However, it seems that with this approach I cannot read the data from
the DAQ with real 50Hz, further it seems that every 10 samples the task
needs to be restarted, which takes longer than the 20ms (corresponding
to the 50Hz target sample rate).
I hope the problem description is clear enough....
Thank you in advance for any advice.
Regards,
Oliver

You have to use the counter together with the analog input to achive this. You could configure the counter to generate 10 pulses with 50 Hz whenever the counter sees a rising edge on the inpput of the counter. The output of the counter would be used as the external clock for the analog input.

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How to sync. 50Hz sample rate with 5Hz external digital trigger signal?

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