Subversion Repositories am9080_cpu_based_on_microcoded_am29xx_bit-slices

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-- Company: 

-- Engineer: 

-- 

-- Create Date: 09/24/2017 01:49:44 PM

-- Design Name: 

-- Module Name: rom32x8 - Behavioral

-- Project Name: 

-- Target Devices: 

-- Tool Versions: 

-- Description: 

-- 

-- Dependencies: 

-- 

-- Revision:

-- Revision 0.01 - File Created

-- Additional Comments:

-- 

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library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

-- Uncomment the following library declaration if using

-- arithmetic functions with Signed or Unsigned values

--use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating

-- any Xilinx leaf cells in this code.

--library UNISIM;

--use UNISIM.VComponents.all;

entity rom32x8 is

    Port ( nCS : in STD_LOGIC;

           address : in STD_LOGIC_VECTOR (3 downto 0);

           data : out STD_LOGIC_VECTOR (4 downto 0));

end rom32x8;

architecture Behavioral of rom32x8 is

signal data_int: std_logic_vector(4 downto 0);

begin

sequence: process(address)

begin

    case address is

        when "0000" =>

            data_int <= "01000"; -- C

        when "0001" =>

            data_int <= "01001"; -- R

        when "0010" =>

            data_int <= "01011"; -- D

        when "0011" =>

            data_int <= "01001"; -- R

        when "0100" =>

            data_int <= "01000"; -- C

        when "0101" =>

            data_int <= "00101"; -- SBR

        when "0110" =>

            data_int <= "01001"; -- R

        when "0111" =>

            data_int <= "00010"; -- RTN

        when "1000" =>

            data_int <= "11010"; -- F

        when "1001" =>

            data_int <= "00101"; -- SBR

        when "1010" =>

            data_int <= "00000"; -- POP

        when "1011" =>

            data_int <= "00001"; -- PR

        when "1100" =>

            data_int <= "01001"; -- R

        when "1101" =>

            data_int <= "00100"; -- PUSH

        when "1110" =>

            data_int <= "01001"; -- R

        when "1111" =>

            data_int <= "11010"; -- F

        when others =>

            data_int <= "11111";

    end case;

end process;

data <= data_int when (nCS = '0') else "ZZZZZ";

end Behavioral;