This problem concerns the design of a circuit to find the sq
Solution
--libraries to be used are specified here
 library IEEE;
 use IEEE.STD_LOGIC_1164.ALL;
 
 --entity declaration with port definitions
 entity syn_count4 is
 port ( clk:     in std_logic;
    reset:   in std_logic;
    counter : out std_logic_vector(3 downto 0)
 );
 end syn_count4;
 
 --architecture of entity
 architecture Behavioral of syn_count4 is
 --signal declaration.
 signal J3,J4,Q1,Q2,Q3,Q4,Qbar1,Qbar2,Qbar3,Qbar4 : std_logic :=\'0\';
 
 begin
 J3 <= Q1 and Q2;
 J4<= J3 and Q3;
 --entity instantiations
 FF1 : entity work.JK_Flipflop port map (clk,\'1\',\'1\',Q1,Qbar1,reset);
 FF2 : entity work.JK_Flipflop port map (clk,Q1,Q1,Q2,Qbar2,reset);
 FF3 : entity work.JK_Flipflop port map (clk,J3,J3,Q3,Qbar3,reset);
 FF4 : entity work.JK_Flipflop port map (clk,J4,J4,Q4,Qbar4,reset);
 counter <= Q4 & Q3 & Q2 & Q1;
 
 end Behavioral;

