Welcome to our corner of expertise at ProgrammingHomeworkHelp.com, where VHDL programming assignment help meets mastery. For students diving into the complexities of VHDL assignments, our seasoned experts provide not just solutions but insights that illuminate the path to understanding. In this post, we unravel the intricacies of VHDL with two master-level questions, accompanied by comprehensive solutions. Let's embark on this journey of VHDL excellence together.
Question 1: Implementing a Finite State Machine (FSM)
Imagine you are tasked with designing a finite state machine (FSM) in VHDL. The FSM has three states: A, B, and C. It has two inputs, X and Y, and one output, Z. The transitions are governed by the following truth table:
| Current State | Input X | Input Y | Next State | Output Z |
|---|---|---|---|---|
| A | 0 | 0 | A | 0 |
| A | 0 | 1 | B | 0 |
| A | 1 | 0 | C | 1 |
| A | 1 | 1 | A | 1 |
| B | 0 | 0 | B | 1 |
| B | 0 | 1 | C | 1 |
| B | 1 | 0 | A | 1 |
| B | 1 | 1 | A | 0 |
| C | 0 | 0 | A | 1 |
| C | 0 | 1 | B | 0 |
| C | 1 | 0 | C | 0 |
| C | 1 | 1 | A | 0 |
Your task is to implement this FSM in VHDL and verify its functionality through simulation.
Solution:
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity FSM is
Port ( clk, reset : in STD_LOGIC;
X, Y : in STD_LOGIC;
Z : out STD_LOGIC);
end FSM;
architecture Behavioral of FSM is
type state_type is (A, B, C);
signal current_state, next_state : state_type;
begin
process (clk, reset)
begin
if reset = '1' then
current_state <= A;
elsif rising_edge(clk) then
current_state <= next_state;
end if;
end process;
process (current_state, X, Y)
begin
case current_state is
when A =>
if (X = '1' and Y = '0') then
next_state <= C;
elsif (X = '1' and Y = '1') then
next_state <= A;
else
next_state <= B;
end if;
Z <= X or Y;
when B =>
if (X = '1' and Y = '1') then
next_state <= A;
else
next_state <= C;
end if;
Z <= X and (not Y);
when others =>
next_state <= A;
Z <= (not X) and Y;
end case;
end process;
end Behavioral;
Explanation:
- The FSM entity has inputs for clock (clk), reset, and two control signals (X and Y), along with an output Z.
- Inside the architecture block, two processes handle state transitions and output computation.
- The first process manages state transitions based on clock edges and reset signal.
- The second process computes the next state and output Z based on the current state and input signals X and Y.
Question 2: Implementing a Binary-to-BCD Converter
Consider the task of designing a binary-to-BCD (Binary-Coded Decimal) converter in VHDL. Your goal is to design a module that takes a 4-bit binary input and outputs the equivalent BCD representation on four 4-bit outputs. Implement this module and verify its functionality.
Solution:
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity Binary_to_BCD is
Port ( binary_in : in STD_LOGIC_VECTOR (3 downto 0);
bcd_out : out STD_LOGIC_VECTOR (15 downto 0));
end Binary_to_BCD;
architecture Behavioral of Binary_to_BCD is
begin
process (binary_in)
begin
case binary_in is
when "0000" =>
bcd_out <= "0000_0000_0000_0000";
when "0001" =>
bcd_out <= "0000_0000_0000_0001";
when "0010" =>
bcd_out <= "0000_0000_0000_0010";
when "0011" =>
bcd_out <= "0000_0000_0000_0011";
when "0100" =>
bcd_out <= "0000_0000_0000_0100";
when "0101" =>
bcd_out <= "0000_0000_0000_0101";
when "0110" =>
bcd_out <= "0000_0000_0000_0110";
when "0111" =>
bcd_out <= "0000_0000_0000_0111";
when "1000" =>
bcd_out <= "0000_0000_0000_1000";
when "1001" =>
bcd_out <= "0000_0000_0000_1001";
when others =>
bcd_out <= "0000_0000_0000_0000"; -- Default case
end case;
end process;
end Behavioral;
Explanation:
- The Binary_to_BCD entity has a 4-bit binary input and a 16-bit BCD output.
- Inside the architecture block, a process is defined to handle the conversion.
- The process uses a case statement to map each possible binary input to its corresponding BCD output.
Conclusion
In this post, we delved into the depths of VHDL programming, unraveling the complexities of finite state machines and binary-to-BCD converters. Armed with these master-level questions and their expert solutions, you're equipped to tackle VHDL assignments with confidence. Remember, at ProgrammingHomeworkHelp.com, we're here to guide you through every step of your VHDL journey. Stay tuned for more insights and solutions from our expert team. Happy coding!
