Untitled

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

entity SevenSegmentControl is
    Port (
        clk : in STD_LOGIC;
        key1, key2, key3, key4 : in STD_LOGIC;
        seven_segment : out STD_LOGIC_VECTOR (6 downto 0)
    );
end SevenSegmentControl;

architecture Behavioral of SevenSegmentControl is
    signal digit : STD_LOGIC_VECTOR (3 downto 0) := "0000"; -- 4-digit binary counter
    signal display_data : STD_LOGIC_VECTOR (6 downto 0);
    
    -- 7-segment display truth table for digits 0-4
    constant seven_segment_data : STD_LOGIC_VECTOR (15 downto 0) := "1000000", -- 0
                                                                   "1111001", -- 1
                                                                   "0100100", -- 2
                                                                   "0110000", -- 3
                                                                   "0011001", -- 4
                                                                   others => "0000000";

begin

    -- Increment the digit on rising edge of the clock
    process (clk)
    begin
        if rising_edge(clk) then
            if key1 = '1' then
                digit <= "0001"; -- Display 1 at units place
            elsif key2 = '1' then
                digit <= "0010"; -- Display 2 at tens place
            elsif key3 = '1' then
                digit <= "0100"; -- Display 3 at hundreds place
            elsif key4 = '1' then
                digit <= "1000"; -- Display 4 at thousands place
            else
                digit <= "0000"; -- Display off when no key is pressed
            end if;
        end if;
    end process;

    -- Assign display_data based on the digit to be displayed
    process (digit)
    begin
        case digit is
            when "0001" =>
                display_data <= seven_segment_data(0);
            when "0010" =>
                display_data <= seven_segment_data(1);
            when "0100" =>
                display_data <= seven_segment_data(2);
            when "1000" =>
                display_data <= seven_segment_data(3);
            when others =>
                display_data <= "0000000"; -- Display off for unknown digit
        end case;
    end process;

    -- Output the display_data to the seven-segment display
    seven_segment <= display_data;

end Behavioral;