Need Help With Code Interpretation on a Code Dealing With Frequency

This is from a code I pulled from another form ( it's the last code posted on the first page of the forum) and I need to annotate it and be able to explain what every thing does but this last part is really throwing me for a loop. Any help you can give would be greatly appreciated XD

    overflows += 1;

ISR(ANALOG_COMP_vect) // interrupt service routine that wraps a user defined function supplied by attachInterrupt
    tnow = TCNT1; // current time
    edges += 1;
      if (edges == 1) { // Start counting edges.
          tstart = overflows*65536 + tnow;
      else if (edges == cycles + 1) { // Stop counting edges.
           tstop = overflows*65536 + tnow;
           // Turn off Timer/Counter 1 and the comparator.
           ACSR = 0; //Analog Comparator Control and Status Register set to zero
           TCCR1B = 0;

I'm using the same code in part of my program and I was wondering the same thing. Haven't figured it out just yet but I'll keep you posted while I dig into it.

Two people with the same IP address woring on the same bit of code.
What are the chances, huh?
Must be assignment time :slight_smile: