Design a BCD converter to drive one and only one of the 7seg

Design a BCD converter to drive one (and only one) of the 7-segment displays on the Basys2 board. For example if a3a2a1a0 = 0011, 3 should appear on the 7-segment display. Write the signal assignments statements for segments a through g using VHDL, as presented in Chapter 10.1 of the text. Implement the converter on the Basys2 board. Remember that the 7-segment displays on the Basys2 board are active-low. Use a VHDL circuit description to do this. Do NOT use Schematic Capture. can you solve it with the circuit.

Solution

The VHDL architectural code for BCD to 7-segment decoder is given below:-

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity decoder1 is
port (
clk : in std_logic;
bcd : in std_logic_vector(3 downto 0); --BCD input
segment7 : out std_logic_vector(6 downto 0) -- 7 bit decoded output.
);
end decoder1;
--\'a\' corresponds to MSB of segment7 and g corresponds to LSB of segment7.
architecture Behavioral of decoder1 is

begin
process (clk,bcd)
BEGIN
if (clk\'event and clk=\'1\') then
case bcd is
when \"0000\"=> segment7 <=\"0000001\"; -- \'0\'
when \"0001\"=> segment7 <=\"1001111\"; -- \'1\'
when \"0010\"=> segment7 <=\"0010010\"; -- \'2\'
when \"0011\"=> segment7 <=\"0000110\"; -- \'3\'
when \"0100\"=> segment7 <=\"1001100\"; -- \'4\'
when \"0101\"=> segment7 <=\"0100100\"; -- \'5\'
when \"0110\"=> segment7 <=\"0100000\"; -- \'6\'
when \"0111\"=> segment7 <=\"0001111\"; -- \'7\'
when \"1000\"=> segment7 <=\"0000000\"; -- \'8\'
when \"1001\"=> segment7 <=\"0000100\"; -- \'9\'
--nothing is displayed when a number more than 9 is given as input.
when others=> segment7 <=\"1111111\";
end case;
end if;

end process;

end Behavioral;