Mealy and Moore outputs
An FSM can have both Mealy-style and Moore-style outputs.
Often the combinational circuit between the
registers and a Moore output is just a wire.
Interconnecting Mealy and Moore “machines”
If you connect a Mealy output of one FSM to an input of another FSM, you need to make sure the delay time through both machines is less than a clock cycle.
Two-phase clocking
In the 70’s, integrated circuits where often made with
using two clock signals,
φ1 and in φ2,
with non-overlapping phases.
The FSM design was broken into two parts, one working during
φ1 and the other, in φ2.
The two parts of the FSM were connected
by latches controlled by different clocks.
Today many circuits are designed with clock domains controlled by different clocks.