State Diagram Feedback in Equations

When you write equations not directly associated with the state diagram (in a separate equations section, for example) and want to decode the current state, you can use either .FB or .Q to refer to the fed-back state register values.

Using .FB is the simplest way to refer to feedback state register values. If you use .Q, you must consider whether 'invert' or 'buffer' was specified for the state registers, and invert the feedback signal accordingly.