MHz range pulse counter

Hi All,

I am having a bit of trouble creating a pulse counter. I have created an oscillator to produce a square wave with upper values of 5.5V and lower values of 3.3V and I would like to get an idea of the RC constant for a given circuit based on the pulse count. The frequency of the pulse is in the MHz range and I want to avoid using interrupts as much as possible due to successive compounding delays.

My idea is to create 2 counters, the first counts the raw amount of impulses and the second record every 10,000 impulses. Then it should display the count on counter 2 and the remainder of counter 1. The purpose of 2 counters is that I would like to run an ISR (interrupt service routine) every time the count restarts (i.e every 10,000). I am using an arduino teensy 3.6 with 8, 32, and 64 bit registers.

Cross post of MHz range pulse counter - Sensors - Arduino Forum
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