Interrupt RPM and Taylors Elapsed time on 18F4620

[Darrel Taylor]

RPM and period numbers per chip
Rpm 4620 877a
5000 15090 14999
6000 12575 12499
7000 10777 10712
8000 9430 9373
9000 8383 8331
10000 7545 7499

I think you need to clear the timer sooner. (Immediately after capture).

The program goes through the whole conversion to RPM with multiplications and DIV32's before clearing the timer.

The 18F's multiply faster because they have a hardware multiplier.
So it clears the timer quicker and ends up with bigger numbers.

The 4620 numbers are closer to reality, but it's still wrong.

Clear the timer immediately after a capture and both chips should read the same numbers (or really close).

hth,