mirror of
git://projects.qi-hardware.com/nn-usb-fpga.git
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543 lines
22 KiB
VHDL
543 lines
22 KiB
VHDL
---------------------------------------------------------------------
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-- TITLE: Plasma Misc. Package
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-- AUTHOR: Steve Rhoads (rhoadss@yahoo.com)
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-- DATE CREATED: 2/15/01
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-- FILENAME: mlite_pack.vhd
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-- PROJECT: Plasma CPU core
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-- COPYRIGHT: Software placed into the public domain by the author.
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-- Software 'as is' without warranty. Author liable for nothing.
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-- DESCRIPTION:
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-- Data types, constants, and add functions needed for the Plasma CPU.
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---------------------------------------------------------------------
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library ieee;
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use ieee.std_logic_1164.all;
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package mlite_pack is
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constant ZERO : std_logic_vector(31 downto 0) :=
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"00000000000000000000000000000000";
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constant ONES : std_logic_vector(31 downto 0) :=
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"11111111111111111111111111111111";
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--make HIGH_Z equal to ZERO if compiler complains
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constant HIGH_Z : std_logic_vector(31 downto 0) :=
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"ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ";
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subtype alu_function_type is std_logic_vector(3 downto 0);
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constant ALU_NOTHING : alu_function_type := "0000";
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constant ALU_ADD : alu_function_type := "0001";
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constant ALU_SUBTRACT : alu_function_type := "0010";
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constant ALU_LESS_THAN : alu_function_type := "0011";
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constant ALU_LESS_THAN_SIGNED : alu_function_type := "0100";
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constant ALU_OR : alu_function_type := "0101";
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constant ALU_AND : alu_function_type := "0110";
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constant ALU_XOR : alu_function_type := "0111";
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constant ALU_NOR : alu_function_type := "1000";
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subtype shift_function_type is std_logic_vector(1 downto 0);
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constant SHIFT_NOTHING : shift_function_type := "00";
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constant SHIFT_LEFT_UNSIGNED : shift_function_type := "01";
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constant SHIFT_RIGHT_SIGNED : shift_function_type := "11";
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constant SHIFT_RIGHT_UNSIGNED : shift_function_type := "10";
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subtype mult_function_type is std_logic_vector(3 downto 0);
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constant MULT_NOTHING : mult_function_type := "0000";
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constant MULT_READ_LO : mult_function_type := "0001";
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constant MULT_READ_HI : mult_function_type := "0010";
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constant MULT_WRITE_LO : mult_function_type := "0011";
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constant MULT_WRITE_HI : mult_function_type := "0100";
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constant MULT_MULT : mult_function_type := "0101";
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constant MULT_SIGNED_MULT : mult_function_type := "0110";
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constant MULT_DIVIDE : mult_function_type := "0111";
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constant MULT_SIGNED_DIVIDE : mult_function_type := "1000";
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subtype a_source_type is std_logic_vector(1 downto 0);
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constant A_FROM_REG_SOURCE : a_source_type := "00";
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constant A_FROM_IMM10_6 : a_source_type := "01";
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constant A_FROM_PC : a_source_type := "10";
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subtype b_source_type is std_logic_vector(1 downto 0);
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constant B_FROM_REG_TARGET : b_source_type := "00";
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constant B_FROM_IMM : b_source_type := "01";
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constant B_FROM_SIGNED_IMM : b_source_type := "10";
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constant B_FROM_IMMX4 : b_source_type := "11";
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subtype c_source_type is std_logic_vector(2 downto 0);
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constant C_FROM_NULL : c_source_type := "000";
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constant C_FROM_ALU : c_source_type := "001";
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constant C_FROM_SHIFT : c_source_type := "001"; --same as alu
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constant C_FROM_MULT : c_source_type := "001"; --same as alu
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constant C_FROM_MEMORY : c_source_type := "010";
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constant C_FROM_PC : c_source_type := "011";
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constant C_FROM_PC_PLUS4 : c_source_type := "100";
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constant C_FROM_IMM_SHIFT16: c_source_type := "101";
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constant C_FROM_REG_SOURCEN: c_source_type := "110";
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subtype pc_source_type is std_logic_vector(1 downto 0);
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constant FROM_INC4 : pc_source_type := "00";
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constant FROM_OPCODE25_0 : pc_source_type := "01";
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constant FROM_BRANCH : pc_source_type := "10";
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constant FROM_LBRANCH : pc_source_type := "11";
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subtype branch_function_type is std_logic_vector(2 downto 0);
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constant BRANCH_LTZ : branch_function_type := "000";
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constant BRANCH_LEZ : branch_function_type := "001";
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constant BRANCH_EQ : branch_function_type := "010";
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constant BRANCH_NE : branch_function_type := "011";
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constant BRANCH_GEZ : branch_function_type := "100";
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constant BRANCH_GTZ : branch_function_type := "101";
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constant BRANCH_YES : branch_function_type := "110";
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constant BRANCH_NO : branch_function_type := "111";
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-- mode(32=1,16=2,8=3), signed, write
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subtype mem_source_type is std_logic_vector(3 downto 0);
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constant MEM_FETCH : mem_source_type := "0000";
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constant MEM_READ32 : mem_source_type := "0100";
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constant MEM_WRITE32 : mem_source_type := "0101";
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constant MEM_READ16 : mem_source_type := "1000";
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constant MEM_READ16S : mem_source_type := "1010";
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constant MEM_WRITE16 : mem_source_type := "1001";
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constant MEM_READ8 : mem_source_type := "1100";
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constant MEM_READ8S : mem_source_type := "1110";
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constant MEM_WRITE8 : mem_source_type := "1101";
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function bv_adder(a : in std_logic_vector;
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b : in std_logic_vector;
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do_add: in std_logic) return std_logic_vector;
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function bv_negate(a : in std_logic_vector) return std_logic_vector;
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function bv_increment(a : in std_logic_vector(31 downto 2)
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) return std_logic_vector;
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function bv_inc(a : in std_logic_vector
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) return std_logic_vector;
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-- For Altera
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COMPONENT lpm_ram_dp
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generic (
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LPM_WIDTH : natural; -- MUST be greater than 0
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LPM_WIDTHAD : natural; -- MUST be greater than 0
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LPM_NUMWORDS : natural := 0;
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LPM_INDATA : string := "REGISTERED";
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LPM_OUTDATA : string := "REGISTERED";
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LPM_RDADDRESS_CONTROL : string := "REGISTERED";
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LPM_WRADDRESS_CONTROL : string := "REGISTERED";
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LPM_FILE : string := "UNUSED";
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LPM_TYPE : string := "LPM_RAM_DP";
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USE_EAB : string := "OFF";
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INTENDED_DEVICE_FAMILY : string := "UNUSED";
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RDEN_USED : string := "TRUE";
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LPM_HINT : string := "UNUSED");
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port (
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RDCLOCK : in std_logic := '0';
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RDCLKEN : in std_logic := '1';
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RDADDRESS : in std_logic_vector(LPM_WIDTHAD-1 downto 0);
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RDEN : in std_logic := '1';
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DATA : in std_logic_vector(LPM_WIDTH-1 downto 0);
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WRADDRESS : in std_logic_vector(LPM_WIDTHAD-1 downto 0);
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WREN : in std_logic;
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WRCLOCK : in std_logic := '0';
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WRCLKEN : in std_logic := '1';
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Q : out std_logic_vector(LPM_WIDTH-1 downto 0));
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END COMPONENT;
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-- For Altera
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component LPM_RAM_DQ
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generic (
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LPM_WIDTH : natural; -- MUST be greater than 0
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LPM_WIDTHAD : natural; -- MUST be greater than 0
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LPM_NUMWORDS : natural := 0;
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LPM_INDATA : string := "REGISTERED";
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LPM_ADDRESS_CONTROL: string := "REGISTERED";
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LPM_OUTDATA : string := "REGISTERED";
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LPM_FILE : string := "UNUSED";
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LPM_TYPE : string := "LPM_RAM_DQ";
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USE_EAB : string := "OFF";
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INTENDED_DEVICE_FAMILY : string := "UNUSED";
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LPM_HINT : string := "UNUSED");
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port (
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DATA : in std_logic_vector(LPM_WIDTH-1 downto 0);
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ADDRESS : in std_logic_vector(LPM_WIDTHAD-1 downto 0);
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INCLOCK : in std_logic := '0';
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OUTCLOCK : in std_logic := '0';
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WE : in std_logic;
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Q : out std_logic_vector(LPM_WIDTH-1 downto 0));
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end component;
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-- For Xilinx
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component RAM16X1D
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-- synthesis translate_off
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generic (INIT : bit_vector := X"16");
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-- synthesis translate_on
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port (DPO : out STD_ULOGIC;
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SPO : out STD_ULOGIC;
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A0 : in STD_ULOGIC;
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A1 : in STD_ULOGIC;
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A2 : in STD_ULOGIC;
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A3 : in STD_ULOGIC;
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D : in STD_ULOGIC;
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DPRA0 : in STD_ULOGIC;
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DPRA1 : in STD_ULOGIC;
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DPRA2 : in STD_ULOGIC;
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DPRA3 : in STD_ULOGIC;
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WCLK : in STD_ULOGIC;
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WE : in STD_ULOGIC);
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end component;
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component pc_next
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port(clk : in std_logic;
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reset_in : in std_logic;
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pc_new : in std_logic_vector(31 downto 2);
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take_branch : in std_logic;
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pause_in : in std_logic;
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opcode25_0 : in std_logic_vector(25 downto 0);
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pc_source : in pc_source_type;
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pc_future : out std_logic_vector(31 downto 2);
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pc_current : out std_logic_vector(31 downto 2);
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pc_plus4 : out std_logic_vector(31 downto 2));
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end component;
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component mem_ctrl
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port(clk : in std_logic;
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reset_in : in std_logic;
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pause_in : in std_logic;
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nullify_op : in std_logic;
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address_pc : in std_logic_vector(31 downto 2);
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opcode_out : out std_logic_vector(31 downto 0);
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address_in : in std_logic_vector(31 downto 0);
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mem_source : in mem_source_type;
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data_write : in std_logic_vector(31 downto 0);
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data_read : out std_logic_vector(31 downto 0);
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pause_out : out std_logic;
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address_next : out std_logic_vector(31 downto 2);
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byte_we_next : out std_logic_vector(3 downto 0);
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address : out std_logic_vector(31 downto 2);
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byte_we : out std_logic_vector(3 downto 0);
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data_w : out std_logic_vector(31 downto 0);
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data_r : in std_logic_vector(31 downto 0));
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end component;
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component control
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port(opcode : in std_logic_vector(31 downto 0);
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intr_signal : in std_logic;
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rs_index : out std_logic_vector(5 downto 0);
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rt_index : out std_logic_vector(5 downto 0);
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rd_index : out std_logic_vector(5 downto 0);
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imm_out : out std_logic_vector(15 downto 0);
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alu_func : out alu_function_type;
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shift_func : out shift_function_type;
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mult_func : out mult_function_type;
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branch_func : out branch_function_type;
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a_source_out : out a_source_type;
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b_source_out : out b_source_type;
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c_source_out : out c_source_type;
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pc_source_out: out pc_source_type;
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mem_source_out:out mem_source_type;
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exception_out: out std_logic);
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end component;
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component reg_bank
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generic(memory_type : string := "XILINX_16X");
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port(clk : in std_logic;
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reset_in : in std_logic;
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pause : in std_logic;
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rs_index : in std_logic_vector(5 downto 0);
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rt_index : in std_logic_vector(5 downto 0);
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rd_index : in std_logic_vector(5 downto 0);
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reg_source_out : out std_logic_vector(31 downto 0);
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reg_target_out : out std_logic_vector(31 downto 0);
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reg_dest_new : in std_logic_vector(31 downto 0);
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intr_enable : out std_logic);
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end component;
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component bus_mux
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port(imm_in : in std_logic_vector(15 downto 0);
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reg_source : in std_logic_vector(31 downto 0);
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a_mux : in a_source_type;
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a_out : out std_logic_vector(31 downto 0);
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reg_target : in std_logic_vector(31 downto 0);
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b_mux : in b_source_type;
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b_out : out std_logic_vector(31 downto 0);
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c_bus : in std_logic_vector(31 downto 0);
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c_memory : in std_logic_vector(31 downto 0);
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c_pc : in std_logic_vector(31 downto 2);
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c_pc_plus4 : in std_logic_vector(31 downto 2);
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c_mux : in c_source_type;
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reg_dest_out : out std_logic_vector(31 downto 0);
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branch_func : in branch_function_type;
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take_branch : out std_logic);
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end component;
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component alu
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generic(alu_type : string := "DEFAULT");
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port(a_in : in std_logic_vector(31 downto 0);
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b_in : in std_logic_vector(31 downto 0);
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alu_function : in alu_function_type;
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c_alu : out std_logic_vector(31 downto 0));
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end component;
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component shifter
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generic(shifter_type : string := "DEFAULT" );
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port(value : in std_logic_vector(31 downto 0);
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shift_amount : in std_logic_vector(4 downto 0);
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shift_func : in shift_function_type;
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c_shift : out std_logic_vector(31 downto 0));
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end component;
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component mult
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generic(mult_type : string := "DEFAULT");
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port(clk : in std_logic;
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reset_in : in std_logic;
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a, b : in std_logic_vector(31 downto 0);
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mult_func : in mult_function_type;
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c_mult : out std_logic_vector(31 downto 0);
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pause_out : out std_logic);
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end component;
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component pipeline
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port(clk : in std_logic;
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reset : in std_logic;
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a_bus : in std_logic_vector(31 downto 0);
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a_busD : out std_logic_vector(31 downto 0);
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b_bus : in std_logic_vector(31 downto 0);
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b_busD : out std_logic_vector(31 downto 0);
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alu_func : in alu_function_type;
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alu_funcD : out alu_function_type;
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shift_func : in shift_function_type;
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shift_funcD : out shift_function_type;
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mult_func : in mult_function_type;
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mult_funcD : out mult_function_type;
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reg_dest : in std_logic_vector(31 downto 0);
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reg_destD : out std_logic_vector(31 downto 0);
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rd_index : in std_logic_vector(5 downto 0);
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rd_indexD : out std_logic_vector(5 downto 0);
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rs_index : in std_logic_vector(5 downto 0);
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rt_index : in std_logic_vector(5 downto 0);
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pc_source : in pc_source_type;
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mem_source : in mem_source_type;
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a_source : in a_source_type;
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b_source : in b_source_type;
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c_source : in c_source_type;
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c_bus : in std_logic_vector(31 downto 0);
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pause_any : in std_logic;
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pause_pipeline : out std_logic);
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end component;
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component mlite_cpu
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generic(memory_type : string := "XILINX_16X"; --ALTERA_LPM, or DUAL_PORT_
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mult_type : string := "DEFAULT";
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shifter_type : string := "DEFAULT";
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alu_type : string := "DEFAULT";
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pipeline_stages : natural := 2); --2 or 3
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port(clk : in std_logic;
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reset_in : in std_logic;
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intr_in : in std_logic;
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address_next : out std_logic_vector(31 downto 2); --for synch ram
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byte_we_next : out std_logic_vector(3 downto 0);
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address : out std_logic_vector(31 downto 2);
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byte_we : out std_logic_vector(3 downto 0);
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data_w : out std_logic_vector(31 downto 0);
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data_r : in std_logic_vector(31 downto 0);
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mem_pause : in std_logic);
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end component;
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component cache
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generic(memory_type : string := "DEFAULT");
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port(clk : in std_logic;
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reset : in std_logic;
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address_next : in std_logic_vector(31 downto 2);
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byte_we_next : in std_logic_vector(3 downto 0);
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cpu_address : in std_logic_vector(31 downto 2);
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mem_busy : in std_logic;
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cache_check : out std_logic; --Stage1: address_next in first 2MB DDR
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cache_checking : out std_logic; --Stage2: cache checking
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cache_miss : out std_logic); --Stage2-3: cache miss
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end component; --cache
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component ram
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generic(memory_type : string := "DEFAULT");
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port(clk : in std_logic;
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enable : in std_logic;
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write_byte_enable : in std_logic_vector(3 downto 0);
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address : in std_logic_vector(31 downto 2);
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data_write : in std_logic_vector(31 downto 0);
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data_read : out std_logic_vector(31 downto 0));
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end component; --ram
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component uart
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generic(log_file : string := "UNUSED");
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port(clk : in std_logic;
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reset : in std_logic;
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enable_read : in std_logic;
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enable_write : in std_logic;
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data_in : in std_logic_vector(7 downto 0);
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data_out : out std_logic_vector(7 downto 0);
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uart_read : in std_logic;
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uart_write : out std_logic;
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busy_write : out std_logic;
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data_avail : out std_logic);
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end component; --uart
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component eth_dma
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port(clk : in std_logic; --25 MHz
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reset : in std_logic;
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enable_eth : in std_logic;
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select_eth : in std_logic;
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rec_isr : out std_logic;
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send_isr : out std_logic;
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address : out std_logic_vector(31 downto 2); --to DDR
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byte_we : out std_logic_vector(3 downto 0);
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data_write : out std_logic_vector(31 downto 0);
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data_read : in std_logic_vector(31 downto 0);
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pause_in : in std_logic;
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mem_address : in std_logic_vector(31 downto 2); --from CPU
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mem_byte_we : in std_logic_vector(3 downto 0);
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data_w : in std_logic_vector(31 downto 0);
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pause_out : out std_logic;
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E_RX_CLK : in std_logic; --2.5 MHz receive
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E_RX_DV : in std_logic; --data valid
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E_RXD : in std_logic_vector(3 downto 0); --receive nibble
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E_TX_CLK : in std_logic; --2.5 MHz transmit
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E_TX_EN : out std_logic; --transmit enable
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E_TXD : out std_logic_vector(3 downto 0)); --transmit nibble
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end component; --eth_dma
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component plasma
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generic(memory_type : string := "XILINX_X16"; --"DUAL_PORT_" "ALTERA_LPM";
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log_file : string := "UNUSED";
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ethernet : std_logic := '0';
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use_cache : std_logic := '0');
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port(clk : in std_logic;
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reset : in std_logic;
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uart_write : out std_logic;
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uart_read : in std_logic;
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address : out std_logic_vector(31 downto 2);
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byte_we : out std_logic_vector(3 downto 0);
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data_write : out std_logic_vector(31 downto 0);
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data_read : in std_logic_vector(31 downto 0);
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mem_pause_in : in std_logic;
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no_ddr_start : out std_logic;
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no_ddr_stop : out std_logic;
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gpio0_out : out std_logic_vector(31 downto 0);
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gpioA_in : in std_logic_vector(31 downto 0));
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end component; --plasma
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component ddr_ctrl
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port(clk : in std_logic;
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clk_2x : in std_logic;
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reset_in : in std_logic;
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address : in std_logic_vector(25 downto 2);
|
|
byte_we : in std_logic_vector(3 downto 0);
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data_w : in std_logic_vector(31 downto 0);
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|
data_r : out std_logic_vector(31 downto 0);
|
|
active : in std_logic;
|
|
no_start : in std_logic;
|
|
no_stop : in std_logic;
|
|
pause : out std_logic;
|
|
|
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SD_CK_P : out std_logic; --clock_positive
|
|
SD_CK_N : out std_logic; --clock_negative
|
|
SD_CKE : out std_logic; --clock_enable
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SD_BA : out std_logic_vector(1 downto 0); --bank_address
|
|
SD_A : out std_logic_vector(12 downto 0); --address(row or col)
|
|
SD_CS : out std_logic; --chip_select
|
|
SD_RAS : out std_logic; --row_address_strobe
|
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SD_CAS : out std_logic; --column_address_strobe
|
|
SD_WE : out std_logic; --write_enable
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|
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SD_DQ : inout std_logic_vector(15 downto 0); --data
|
|
SD_UDM : out std_logic; --upper_byte_enable
|
|
SD_UDQS : inout std_logic; --upper_data_strobe
|
|
SD_LDM : out std_logic; --low_byte_enable
|
|
SD_LDQS : inout std_logic); --low_data_strobe
|
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end component; --ddr
|
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end; --package mlite_pack
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package body mlite_pack is
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function bv_adder(a : in std_logic_vector;
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b : in std_logic_vector;
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|
do_add: in std_logic) return std_logic_vector is
|
|
variable carry_in : std_logic;
|
|
variable bb : std_logic_vector(a'length-1 downto 0);
|
|
variable result : std_logic_vector(a'length downto 0);
|
|
begin
|
|
if do_add = '1' then
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|
bb := b;
|
|
carry_in := '0';
|
|
else
|
|
bb := not b;
|
|
carry_in := '1';
|
|
end if;
|
|
for index in 0 to a'length-1 loop
|
|
result(index) := a(index) xor bb(index) xor carry_in;
|
|
carry_in := (carry_in and (a(index) or bb(index))) or
|
|
(a(index) and bb(index));
|
|
end loop;
|
|
result(a'length) := carry_in xnor do_add;
|
|
return result;
|
|
end; --function
|
|
|
|
|
|
function bv_negate(a : in std_logic_vector) return std_logic_vector is
|
|
variable carry_in : std_logic;
|
|
variable not_a : std_logic_vector(a'length-1 downto 0);
|
|
variable result : std_logic_vector(a'length-1 downto 0);
|
|
begin
|
|
not_a := not a;
|
|
carry_in := '1';
|
|
for index in a'reverse_range loop
|
|
result(index) := not_a(index) xor carry_in;
|
|
carry_in := carry_in and not_a(index);
|
|
end loop;
|
|
return result;
|
|
end; --function
|
|
|
|
|
|
function bv_increment(a : in std_logic_vector(31 downto 2)
|
|
) return std_logic_vector is
|
|
variable carry_in : std_logic;
|
|
variable result : std_logic_vector(31 downto 2);
|
|
begin
|
|
carry_in := '1';
|
|
for index in 2 to 31 loop
|
|
result(index) := a(index) xor carry_in;
|
|
carry_in := a(index) and carry_in;
|
|
end loop;
|
|
return result;
|
|
end; --function
|
|
|
|
|
|
function bv_inc(a : in std_logic_vector
|
|
) return std_logic_vector is
|
|
variable carry_in : std_logic;
|
|
variable result : std_logic_vector(a'length-1 downto 0);
|
|
begin
|
|
carry_in := '1';
|
|
for index in 0 to a'length-1 loop
|
|
result(index) := a(index) xor carry_in;
|
|
carry_in := a(index) and carry_in;
|
|
end loop;
|
|
return result;
|
|
end; --function
|
|
|
|
end; --package body
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