What is quadrature and 4X (4 times) quadrature encoding?
Quadrature is a description of the 90 degrees out of phase between channel A and B. The rising edge to rising edge (referred as the Cycle) on channel A or B indicates that one set of bars (on the internal encoder disk) have passed by the optical sensor. The quadrature state of channels A and B create four unique logic states. Each group of four states is decoded as one directional count. These four unique logic states are decoded. 4x counting usually refers to a counter which may be configured to recognize each quadrature state as a separate count. So with this in mind 250 sets of bars would yield 1000 counts.
