| Finite State Machines. For synthesis When modeling finite state machines, it is recommended to separate the sequential current-state logic from the com- binational next-state and output logic.State Diagram for lack of space the outputs are not shown on the state diagram, but are: in state0: Zot = 000, in state1: Zot = 101, in state2: Zot = 111, in state3: Zot = 001.  Using Macros for state definitionAs an alternative for-parameter state0=0, state1=1,state2=2, state3=3; one can use macros. For example after the definition below 2’d0 will be textually substituted whenever `state0 is used. `define state0 2’d0 `define state1 2’d1 `define state2 2’d `define state3 2’d3; When using macro definitionsone must put a back quote in front. For example: case (state) `state0: Zot = 3’b000; `state1: Zot = 3’b101; `state2: Zot = 3’b111; `state3: Zot = 3’b001;  CountersCounters are a simple type of finite-state machine where separation of the flip-flop generation code and the next-state generation code is not worth the effort. In such code, use the nonblocking “<=” assignment operator. Binary Counter Using toggle flip-flops   Shift Registers Shift registers are also best done completely in the flip-flop generation code. Use the nonblocking “<=” assignment operator so the operators “<< N” shifts left N bits. The operator “>>N” shifts right N bits.Shift Register  Linear-Feedback Shift Register   |
Finite State Machines.
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Updated on May 4, 2025
