Patrick B. Murphy <PICLIST@mitvma.mit.edu> wrote:

> I would like to update the display twice a second.

    So forget about capture/compare modules, etc., and just count
    pulses on each of the 12 inputs for half a second.

    Would be much easier than all that other silliness... And if you
    count pulses for 0.46875 seconds instead of 0.5 seconds, you can
    convert your count of pulses directly to RPM by just
    left-shifting it 3 positions.

    Doing it this way gives you 4% resolution at 200 RPM; if that's
    not enough, run the counts through a moving-window average to get
    finer resolution.

    -Andy

=== Andrew Warren -- aiw@cypress.com
=== Principal Design Engineer
=== Cypress Semiconductor Corporation
===
=== Opinions expressed above do not
=== necessarily represent those of
=== Cypress Semiconductor Corporation

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