Design of SR Flip Flop using Behavior Modeling Style (VHDL Code).

Design of SR Flip Flop using Behavior Modeling Style -

Output Waveform :   SR (Set - Reset)  Flip Flop

VHDL Code -



-------------------------------------------------------------------------------
--
-- Title       : sr_flip_flop
-- Design      : vhdl_upload 1
-- Author      : Naresh Singh Dobal
-- Company     : nsd       
-- VHDL Tutorials & exercise by Naresh Singh Dobal
--
-------------------------------------------------------------------------------
--
-- File        : SR Flip Flop.vhd


library IEEE;
use IEEE.STD_LOGIC_1164.all;

entity sr_flip_flop is
     port(
         s : in STD_LOGIC;
         r : in STD_LOGIC;
         clk : in STD_LOGIC;
         reset : in STD_LOGIC;
         q : out STD_LOGIC;
         qb : out STD_LOGIC
         );
end sr_flip_flop;

architecture sr_flip_flop_arc of sr_flip_flop is
begin

    srff : process (s,r,clk,reset) is
    begin
        if (reset='1') then
            q <= '0';
            qb <= '1';
        elsif (rising_edge (clk)) then
            if (s/=r) then
                q <= s;
                qb <= r;
            elsif (s='1' and r='1') then
                q <= 'Z';
                qb <= 'Z';
            end if;
        end if;
    end process srff;
   

end sr_flip_flop_arc;