Hi all, I did the measure time between pulses approach for a project=20
that needed fine user control on 1K steps of PWM for LEDs.  It worked=20
but was a little finnicky, some further refinement that wasn't worth the=20
time probably would have improved things.

So turning the knob slowly stepped by 1, and fast did bigger (10s or=20
more) jumps.

I suggest having it be that you need to see more than 1 step in the=20
reverse direction before changing the step speed/direction.  Part of the=20
nuisance is the need to debounce the encoder signals while also=20
responding to fast moving changes.  Also if you're stepping by 100s, for=20
example, and see a reverse, maybe it should reverse by 100 and not 1s,=20
unless a half second or more has elapsed since the last step by 100.=20
Lots of room for timing constants and tweaks here.

The timer setting on my (guess) early 1990s oven takes this approach,=20
setting single seconds vs. 15 second jumps vs. minute jumps vs 5 minute=20
jumps, and when reversing direction it does the reverse jump by the same=20
amount as forward, and has a short (200msec?) timeout whereby no change=20
=3D go back to single seconds.  All this works better than the thing I=20
made (which has no readout to help tell the user what's going on).

Just my 2c.

J



Kerry wrote:
> One way I have thought about (but have not tried yet) is to use a
> mechanical encoder.
> Step by 1s.  If you see 10 steps in the same direction, start stepping
> by 10s.
> If you see 10 steps of 10 in the same direction, start stepping by 100s.
> If you see 10 steps of 100 in the same direction, start stepping by 1000s=
..
> If you see a step in the opposite direction, go back to stepping by 1s.
> I don't know if this would be more of a PITA than it's worth.
> An alternative would be to measure the time between encoder pulses, and
> take bigger steps for quicker pulses.
>
> Kerry
>
--=20
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