Counter in Digital Discovery

[Mavitaka]

Hi,

I hope that you are doing well.

I would like to ask if it is possible to make a counter to count between two pulses in Digital Discovery?

I want to use PPS (pulse per sesond) from GPS to trigger the acquisition.

And I want to use a counter to be sure that the duration between 2 PPS is exactly 1 second (with 10ns precision or less).

Thank you in advance for your reply.

Best regards.

 

[attila]

Hi @Mavitaka

See the Counter in the Logic Analyzer.

Here 1Hz is generated by one device and captured by another. The difference is the crystal oscillators tolerance.

[Mavitaka]

Hi @attila,

Thank for your answer.

I have tried and received something like in the photo below.

I have one question.

You said that the difference is the crystal oscillators tolerance.

So the PPS period that I got is 1.00000385 s and not exactly 1s is because of the crystal oscillator of the digital discovery and not because of the GPS precision?

That is it?

Thank you in advance for your reply.

Best regards.

[attila]

Hi @Mavitaka

The GPS satellites use atomic clocks which are extremely precise and these also take in account the time dilation.
I don't know how accurately does the receiver forward the signal but probably it is still more precise than any device using crystal oscillator.