Quadrature Encoder Error Question

Well, yes, that should of course have been: a common output configuration is A, A Not, B, B Not, Z, and Z Not.

The 2 bit pattern comparison should guard against noise and going to fast for the micro type scenario.
Using the Z input should guard against counting errors.

Should be good enough for me for now.

Will start to work on the library.

Cheers
Kim