Subversion Repositories opencpu32

--! @file

--! @brief 2:1 CPU global Definitions

--! @mainpage

--! <H1>Main document of the OpenCPU32 project</H1>\n

--! <H2>Features</H2>

--! Use standard library

library IEEE;

use IEEE.STD_LOGIC_1164.all;

package pkgOpenCPU32 is

--! Declare constants, enums, functions used by the design

constant nBits          : integer := 32;

--! Number of general registers (r0..r15)

constant numGenRegs : integer := 16;

type aluOps is (alu_pass, alu_passB, alu_sum, alu_sub, alu_inc, alu_dec, alu_mul, alu_or, alu_and,

        alu_xor, alu_not, alu_shfLt, alu_shfRt, alu_roLt, alu_roRt);

type typeEnDis is (enable, disable);

type generalRegisters is (r0,r1,r2,r3,r4,r5,r6,r7,r8,r9,r10,r11,r12,r13,r14,r15);

type dpMuxInputs is (fromMemory, fromImediate, fromRegFileA, fromRegFileB, fromAlu);

function reg2Num (a: generalRegisters) return integer;

function Num2reg (a: integer) return generalRegisters;

function muxPos( a: dpMuxInputs) return std_logic_vector;

end pkgOpenCPU32;

--! Define functions or procedures

package body pkgOpenCPU32 is

function muxPos( a: dpMuxInputs) return std_logic_vector is

variable valRet : std_logic_vector(2 downto 0);

begin

        case a is

                when fromMemory => valRet := "000";

                when fromImediate => valRet := "001";

                when fromRegFileA => valRet := "010";

                when fromRegFileB => valRet := "011";

                when fromAlu => valRet := "100";

        end case;

        return valRet;

end muxPos;

function reg2Num (a: generalRegisters) return integer is

  variable valRet : integer;

  begin

    case a is

                when r0 => valRet := 0;

                when r1 => valRet := 1;

                when r2 => valRet := 2;

                when r3 => valRet := 3;

                when r4 => valRet := 4;

                when r5 => valRet := 5;

                when r6 => valRet := 6;

                when r7 => valRet := 7;

                when r8 => valRet := 8;

                when r9 => valRet := 9;

                when r10 => valRet := 10;

                when r11 => valRet := 11;

                when r12 => valRet := 12;

                when r13 => valRet := 13;

                when r14 => valRet := 14;

                when r15 => valRet := 15;

         end case;

         return valRet;

  end reg2Num;

function Num2reg (a: integer) return generalRegisters is

  variable valRet : generalRegisters;

  begin

    case a is

                when 0 => valRet := r0;

                when 1 => valRet := r1;

                when 2 => valRet := r2;

                when 3 => valRet := r3;

                when 4 => valRet := r4;

                when 5 => valRet := r5;

                when 6 => valRet := r6;

                when 7 => valRet := r7;

                when 8 => valRet := r8;

                when 9 => valRet := r9;

                when 10 => valRet := r10;

                when 11 => valRet := r11;

                when 12 => valRet := r12;

                when 13 => valRet := r13;

                when 14 => valRet := r14;

                when 15 => valRet := r15;

                when others => valRet := r0;

         end case;

         return valRet;

  end Num2reg;

end pkgOpenCPU32;