Write a VHDL code for logic gates (AND gate, OR gate) and simulate the code.
To Develop code for logic gates. Simulate the code in the software.
1. Xilinx Software Loaded PC = 1.
2. Printer = 1.
Procedure for doing the exercise/experiment:
4. Flow Chart
5. VHDL Code Writing
6. Compile and Run program.
A test bench is a virtual environment used to verify the correctness of a design or model called “design under test”. A test bench has four components…
1. Input: the signals needed to perform work
2. Procedures to do: the tasks or processes that will transform the input into the output
3. Procedures to check: the processes that determine that the output meets the standards
4. Output: The output signals produced from the workbench
1. Define Library functions.
2. Declare Entity and Architecture.
3. Describe functionality.
4. End source code and define Test Bench.
5. Compile and Run program
Develop a VHDL test bench code for testing any one of the simple gate. Simulate the test bench code in the HDL software.
Code Listing (AND gate program)
library IEEE; use IEEE.STD_LOGIC_1164.ALL; use IEEE.STD_LOGIC_ARITH.ALL; use IEEE.STD_LOGIC_UNSIGNED.ALL; entity gate is Port ( a: in STD_LOGIC; b: in STD_LOGIC; c: out STD_LOGIC); end gate; architecture Behavioral of gate is begin c <= a and b; end Behavioral;
AND Gate Output Waveform:
Code Listing ( OR gate program)
library IEEE; use IEEE.STD_LOGIC_1164.ALL; use IEEE.STD_LOGIC_ARITH.ALL; use IEEE.STD_LOGIC_UNSIGNED.ALL; entity gate is Port ( a: in STD_LOGIC; b: in STD_LOGIC; c: out STD_LOGIC); end gate; architecture Behavioral of gate is begin c <= a or b; end Behavioral;
OR Gate Output Waveform:
Thus a test bench for the given logic gate was simulated.
Questions with answers:
1. Software name? Ans: Xilinx Software
2. SOP Means? Ans: Sum of Product
3. How many Types of VLSI Programming Language?
(a) VHDL (Very High speed Hardware Description Language)
(b) Verilog Type
4. What is AND gate Boolean Expression? Ans: Y = A.B
5. What is OR gate Boolean Expression? Ans: Y = A+B
AND Gate Video Tutorial:
OR Gate Video Tutorial: