I think you'll quickly understand you'll have to use interrupts and ... a 16Bits timer ... what the 16F84 doesn't have aboard ...
so, you'll also have to watch for TMR0 overflows ...to increment a 8 bits counter for the timer Upper 8 bits counting.
I'll go along and try to use the CCP on Pic16F628A :-)
I'll be back with updates.


Thanks for the fast replies!