Yes, I understand that, questiton is, how do
you represent that using a single pin ?
Jan-Erik.

PS.
And I think you should have read the rest of the thread before replying...
DS.

Tal wrote:

There are two sensors in a slight angular shift. They are designed such
that there is overlap between there pulses. When you rotate the wheel in
one direction you get

A B
0 0
0 1
1 1
1 0
0 0

And when in the other direction you get this sequence reversed. A simple
finite state machine is used to extract from these sequences Increment
and Decrement pulses. The finite state machine is designed such that
even if the wheels changes direction arbitrarily, you don't accomulate
any error.

Tal

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