Implement 'Implicit Buffered Read' using Ex VI 'Count Edges'

I am trying to implement Implicit Buffered Read (see image below) or page:

https://www.ni.com/docs/en-US/bundle/testscale-feature/page/counter-read.html

Labview 2021 SP1 Pro, cDAQ chassis 8189, 9402 dio module

I have a square wave begin generated (function generator) on pfi0 on the chassis.  Would pfi0 suffice as the 'counter timebase'?

I have another sqare wave signal coming in on the 9402, ch0, acting as my Signal to measure.

I'm using the Count Edges.vi from Example Finder.  The VI runs, but the counter value just spins, ie increases dramatically.

If I want to acquire in finite mode for 8 seconds, do I DAQmxStart, wait for 8 seconds, and then DAQmxRead, which will read the entire buffer?

Regards,

Gretchen