VHDL code for OR gate with Test bench

VHDL code for OR gate with Test bench

 



library IEEE;
use IEEE.std_logic_1164.all;
entity orgate is
Port( A : in std_logic;
B : in std_logic;
Y : out std_logic
);
end orgate;

architecture Behavioral of orgate is
begin
Y<= A  or B ;
end Behavioral;

Test Bench

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
entity or_tb is
--  Port ( );
end or_tb;

architecture Behavioral of or_tb is
--Component name and entity's name must be same
--ports must be same 
 component orgate is
  Port (A,B:in std_logic;
  C: out std_logic );
end component;
--inputs
signal a: std_logic:= '0';
signal b: std_logic:= '0';
--outputs
signal c : std_logic;

begin
uut: orgate PORT MAP(a=>A,b=>B,c=>C);
--Stimulus Process
stim_proc:process
begin
wait for 10ns;
a<='1';
b<='0';
wait for 10ns;
a<='0';
b<='1';
wait for 10ns;
a<='0';
b<='0';
wait for 10ns;
a<='1';
b<='1';
wait for 10ns;
end process;
end Behavioral;

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