Vhdl Code For Serial Adder Using Finite State Machine

  1. Vhdl Code For Serial Adder Using Finite State Machine Diagram
  2. Vhdl Code For Serial Adder Using Finite State Machine Calculator

Yet another approach to write the VHDL code for the state machine is to create a structural model. The structural model describes all actual gates and flip-flops and their connectivity. An example of this is shown in Fig. 2-58, page 108, in the textbook. Finally, there is yet another way of describing a state machine: state machine editor. 23 Finite State Machine 03 31 Moor and Mealy type FSMs state re assignment Lecture 24 VHDL Lecture 25 Serial Adder 04 04 VHDL Verilog Code For Serial Adder Fsm pdf DOWNLOAD HERE 1 2 Full Verilog code for Moore FSM Sequence Detector April 21st, 2019 - This Verilog project is to present a full Verilog code for Sequence.

The serial adder is a digital circuit in which bits are added a pair at a time.

Let A and B be two unsigned numbers to be added to produce Sum = A + B. In this we are using three shift registers which are used to hold A, B and Sum. Now in each clock cycle, a pair of bits is added by the adder FSM and at the end of the cycle, the resulting sum is shifted into the Sum register.

Mealy type FSM for serial adder:

Let G and H denote the states where the carry-in-values are 0 and 1. Output value s depends on both the state and the present value of inputs a and b.

In state G and H:

Input valuationOutput (s)State
000FSM will remain in same state G
01,101FSM will remain in same state G
110FSM moves to state H
01,100FSM will remain in same state H
111FSM will remain in same state H
001FSM moves to state G

A single Flip-Flop is needed to represent the two states. The next state and output equations are:

Y = ab + ay + by

s = a ⊕ b ⊕ y

Vhdl Code For Serial Adder Using Finite State Machine

The flip-flop can be cleared by the Reset signal at the start of the addition operation.

Moore type FSM for serial adder:

In a Moore type FSM, output depends only on the present state. Since in both states, G and H, it is possible to produce two different outputs depending on the valuations of the inputs a and b, a Moore type FSM will need more than two states. Therefore we will four states namely: G0, G1, H0 and H1.

The next state and output equations are:

Y1 = a ⊕ b ⊕ y2

Y2 = ab + by2 + by2

Vhdl Code For Serial Adder Using Finite State Machine Diagram

s = y1

The only difference between circuits of Mealy and Moore type FSM for serial adder is that in Moore type FSM circuit, output signal s is passed through an extra flip-flop and thus delayed by one clock cycle with respect to the Mealy type FSM circuit.

Vhdl Code For Serial Adder Using Finite State Machine Calculator

References: Fundamentals of Digital Logic with VHDL Design