（1）编写VHDL程序，实现具有七条MIPS指令功能的控制器。 （2）七条指令分别为：ADDU SUBU BNEZ JR OR LW SW。

以下是一个实现七条MIPS指令功能的控制器的VHDL程序：

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.NUMERIC_STD.ALL;

entity MIPS_Controller is
    Port ( instruction : in  std_logic_vector(31 downto 0);
           PC : in  std_logic_vector(31 downto 0);
           RegDst : out  std_logic;
           Branch : out  std_logic;
           MemRead : out  std_logic;
           MemtoReg : out  std_logic;
           ALUOp : out  std_logic_vector(2 downto 0);
           MemWrite : out  std_logic;
           ALUSrc : out  std_logic;
           RegWrite : out  std_logic);
end MIPS_Controller;

architecture Behavioral of MIPS_Controller is

begin

    process (instruction(31 downto 26))
    begin
        case instruction(31 downto 26) is
            
            -- ADDU: 000000
            when "000000" =>
                RegDst <= '1';
                Branch <= '0';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "001";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '1';
                
            -- SUBU: 000000
            when "000000" =>
                RegDst <= '1';
                Branch <= '0';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "011";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '1';
                
            -- BNEZ: 000101
            when "000101" =>
                RegDst <= '0';
                Branch <= '1';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "010";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '0';
                
            -- JR: 000010
            when "000010" =>
                RegDst <= '0';
                Branch <= '1';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "000";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '0';
                
            -- OR: 000000
            when "000000" =>
                RegDst <= '1';
                Branch <= '0';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "110";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '1';
                
            -- LW: 100011
            when "100011" =>
                RegDst <= '0';
                Branch <= '0';
                MemRead <= '1';
                MemtoReg <= '1';
                ALUOp <= "010";
                MemWrite <= '0';
                ALUSrc <= '1';
                RegWrite <= '1';
                
            -- SW: 101011
            when "101011" =>
                RegDst <= '0';
                Branch <= '0';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "010";
                MemWrite <= '1';
                ALUSrc <= '1';
                RegWrite <= '0';
                
            -- Default
            when others =>
                RegDst <= '0';
                Branch <= '0';
                MemRead <= '0';
                MemtoReg <= '0';
                ALUOp <= "000";
                MemWrite <= '0';
                ALUSrc <= '0';
                RegWrite <= '0';
                
        end case;
    end process;

end Behavioral;

该控制器将输入的32位指令解码为七个控制信号，这些控制信号被发送到MIPS处理器的不同模块，以执行相应的操作。这七个指令分别是ADDU、SUBU、BNEZ、JR、OR、LW和SW。