ALUControlUnit.vhd

LIBRARY ieee;
USE ieee.std_logic_1164.ALL;
ENTITY ALUControlUnit IS PORT (
    OpCode : IN STD_LOGIC_VECTOR(4 DOWNTO 0);
    ALUOP : OUT STD_LOGIC_VECTOR(3 DOWNTO 0)
);

END ALUControlUnit;

ARCHITECTURE ALUControlUnitArch OF ALUControlUnit IS
BEGIN
WITH OpCode SELECT
ALUOP <=
    "0000" WHEN "00000", -- NOP
    "0000" WHEN "00001", -- IN
    "0000" WHEN "00010", -- SWAP
    "0010" WHEN "00011", -- ADD
    "0010" WHEN "00100", -- ADDI
    "0011" WHEN "00101", -- SUB
    "0100" WHEN "00110", -- AND
    "0101" WHEN "00111", -- OR
    "0110" WHEN "01000", -- XOR
    "1110" WHEN "01001", -- pop
    "0001" WHEN "01010", -- LDM
    "0001" WHEN "01011", -- LDD
    "1110" WHEN "01100", -- RET
    "1110" WHEN "01101", -- RTI
    "0111" WHEN "10000", 
    "1000" WHEN "10001",
    "1001" WHEN "10010",
    "1010" WHEN "10011",
    "0000" WHEN "10100",
    "0011" WHEN "10101", -- CMP
    "1101" WHEN "10110", -- BITSET
    "1011" WHEN "10111", -- RCL
    "1100" WHEN "11000", -- RCR
    "1111" WHEN "11001", -- PUSH
    "0001" WHEN "11010", -- STD
    "0000" WHEN "11011", -- PROTECT
    "0000" WHEN "11100", -- FREE
    "0000" WHEN "11101", -- JZ
    "0000" WHEN "11110", -- JMP
    "1111" WHEN "11111", -- CALL
    "0000" WHEN OTHERS;
END ALUControlUnitArch;