Subversion Repositories socwire

---====================== Start Software License ========================---

--==                                                                    ==--

--== This license governs the use of this software, and your use of     ==--

--== this software constitutes acceptance of this license. Agreement    ==--

--== with all points is required to use this software.                  ==--

--==                                                                    ==--

--== 1. This source file may be used and distributed without            ==--

--== restriction provided that this software license statement is not   ==--

--== removed from the file and that any derivative work contains the    ==--

--== original software license notice and the associated disclaimer.    ==--

--==                                                                    ==--

--== 2. This source file is free software; you can redistribute it      ==--

--== and/or modify it under the restriction that UNDER NO CIRCUMTANCES  ==--

--== this Software is to be used to CONSTRUCT a SPACEWIRE INTERFACE     ==--

--== This implies modification and/or derivative work of this Software. ==--

--==                                                                    ==--

--== 3. This source is distributed in the hope that it will be useful,  ==--

--== but WITHOUT ANY WARRANTY; without even the implied warranty of     ==--

--== MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.               ==--

--==                                                                    ==--

--== Your rights under this license are terminated immediately if you   ==--

--== breach it in any way.                                              ==--

--==                                                                    ==--

---======================= End Software License =========================---

---====================== Start Copyright Notice ========================---

--==                                                                    ==--

--== Filename ..... socwire_codec.vhd                                   ==--

--== Download ..... http://www.ida.ing.tu-bs.de                         ==--

--== Company ...... IDA TU Braunschweig, Prof. Dr.-Ing. Harald Michalik ==--

--== Authors ...... Björn Osterloh, Karel Kotarowski                    ==--

--== Contact ...... Björn Osterloh (b.osterloh@tu-bs.de)                ==--

--== Copyright .... Copyright (c) 2008 IDA                              ==--

--== Project ...... SoCWire CODEC                                       ==--

--== Version ...... 1.00                                                ==--

--== Conception ... 11 November 2008                                    ==--

--== Modified ..... N/A                                                 ==--

--==                                                                    ==--

---======================= End Copyright Notice =========================---

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

USE WORK.ALL;

ENTITY socwire_codec IS

  GENERIC(

          --== Set Codec Speed to system clock in nanoseconds! ==--

          --== USE GEREIC MAPPING FROM TOPLEVEL!!!             ==--

               bitwidth : NATURAL RANGE 8 TO 8192;

               speed    : NATURAL RANGE 1 TO 100

         );

  PORT(

       --==  General Interface (Sync Rst, 50MHz Clock) ==--

       rst        : IN  STD_LOGIC;

       clk        : IN  STD_LOGIC;

       --== Link Enable Interface ==--

       enable     : IN  STD_LOGIC;

       disable    : IN  STD_LOGIC;

       --== Serial Receive Interface ==--

       rx         : IN  STD_LOGIC_VECTOR(bitwidth+1 DOWNTO 0);

       rx_valid   : IN  STD_LOGIC;

       --== Serial Transmit Interface ==--

       tx         : OUT STD_LOGIC_VECTOR(bitwidth+1 DOWNTO 0);

       tx_valid   : OUT STD_LOGIC;

       --== Data Input Interface ==--

       dat_full   : OUT STD_LOGIC;

       dat_nwrite : IN  STD_LOGIC;

       dat_din    : IN  STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== Data Output Interface ==--

       dat_nread  : IN  STD_LOGIC;

       dat_empty  : OUT STD_LOGIC;

       dat_dout   : OUT STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== Active Interface ==--

       active     : OUT STD_LOGIC

      );

END socwire_codec;

ARCHITECTURE rtl OF socwire_codec IS

---==========================---

--== Constants Declarations ==--

---==========================---

CONSTANT st_error_reset : STD_LOGIC_VECTOR(2 DOWNTO 0) := "000";

CONSTANT st_error_wait  : STD_LOGIC_VECTOR(2 DOWNTO 0) := "001";

CONSTANT st_ready       : STD_LOGIC_VECTOR(2 DOWNTO 0) := "010";

CONSTANT st_started     : STD_LOGIC_VECTOR(2 DOWNTO 0) := "011";

CONSTANT st_connecting  : STD_LOGIC_VECTOR(2 DOWNTO 0) := "100";

CONSTANT st_run         : STD_LOGIC_VECTOR(2 DOWNTO 0) := "101";

CONSTANT st_unknown_1   : STD_LOGIC_VECTOR(2 DOWNTO 0) := "110";

CONSTANT st_unknown_2   : STD_LOGIC_VECTOR(2 DOWNTO 0) := "111";

---===================================---

--== Signal Declarations (SM to All) ==--

---===================================---

SIGNAL state : STD_LOGIC_VECTOR(2 DOWNTO 0);

---==================================---

--== Signal Declarations (Rx to SM) ==--

---==================================---

SIGNAL got_null  : STD_LOGIC;

SIGNAL got_fct   : STD_LOGIC;

SIGNAL got_nchar : STD_LOGIC;

SIGNAL err_par   : STD_LOGIC;

SIGNAL err_esc   : STD_LOGIC;

SIGNAL err_dsc   : STD_LOGIC;

SIGNAL err_fct   : STD_LOGIC;

SIGNAL err_nchar : STD_LOGIC;

---=======================================---

--== Signal Declarations (Rx to Rx FIFO) ==--

---=======================================---

SIGNAL dat_full_i   : STD_LOGIC;

SIGNAL dat_nwrite_i : STD_LOGIC;

SIGNAL dat_din_i    : STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

---=======================================---

--== Signal Declarations (Rx FIFO to Tx) ==--

---=======================================---

SIGNAL fct_nread_i : STD_LOGIC;

SIGNAL fct_empty_i : STD_LOGIC;

---=======================================---

--== Signal Declarations (Rx to Tx FIFO) ==--

---=======================================---

SIGNAL fct_full_i   : STD_LOGIC;

SIGNAL fct_nwrite_i : STD_LOGIC;

---=======================================---

--== Signal Declarations (Tx FIFO to Tx) ==--

---=======================================---

SIGNAL dat_nread_i : STD_LOGIC;

SIGNAL dat_empty_i : STD_LOGIC;

SIGNAL dat_dout_i  : STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

---=============================================---

--== TESTBENCH : Type Declarations : TESTBENCH ==--

---=============================================---

TYPE ss IS

  (

   error_reset,

   error_wait,

   ready,

   started,

   connecting,

   run,

   unknown_1,

   unknown_2,

   baffled

  );

---===============================================---

--== TESTBENCH : Signal Declarations : TESTBENCH ==--

---===============================================---

SIGNAL codec_state : ss;

---=============================================---

--== Component Instantiations for leaf modules ==--

---=============================================---

COMPONENT receiver

  GENERIC(

            bitwidth : NATURAL RANGE 8 TO 8192;

            speed        : NATURAL RANGE 1 TO 100

         );

        PORT(

       --== General Interface (Sync Rst, 50MHz Clock) ==--

       rst       : IN  STD_LOGIC;

       clk       : IN  STD_LOGIC;

       --== SoCWire Interface ==--

       state     : IN  STD_LOGIC_VECTOR(2 DOWNTO 0);

       --== External Receive Interface ==--

       rx                : IN  STD_LOGIC_VECTOR(bitwidth+1 DOWNTO 0);

       rx_valid  : IN  STD_LOGIC;

       --== Character Interface ==--

       got_null  : OUT STD_LOGIC;

       got_fct   : OUT STD_LOGIC;

       got_nchar : OUT STD_LOGIC;

       --== Error Interface ==--

       err_par   : OUT STD_LOGIC;

       err_esc   : OUT STD_LOGIC;

       err_dsc   : OUT STD_LOGIC;

       err_fct   : OUT STD_LOGIC;

       err_nchar : OUT STD_LOGIC;

       --== Data Output Interface ==--

       dat_nread : IN  STD_LOGIC;

       dat_empty : OUT STD_LOGIC;

       dat_dout  : OUT STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== FCT Output Interface ==--

       fct_nread : IN  STD_LOGIC;

       fct_empty : OUT STD_LOGIC

      );

END COMPONENT;

COMPONENT receive_fifo

  GENERIC(

          bitwidth : NATURAL RANGE 8 TO 8192

         );

        PORT(

       --== General Interface (Sync Rst, 50MHz Clock) ==--

       rst        : IN  STD_LOGIC;

       clk        : IN  STD_LOGIC;

       --== SoCWire Interface ==--

       state      : IN  STD_LOGIC_VECTOR(2 DOWNTO 0);

       --== Data Input Interface ==--

       dat_full   : OUT STD_LOGIC;

       dat_nwrite : IN  STD_LOGIC;

       dat_din    : IN  STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== Data Output Interface ==--

       dat_nread  : IN  STD_LOGIC;

       dat_empty  : OUT STD_LOGIC;

       dat_dout   : OUT STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== FCT Output Interface ==--

       fct_nread  : IN  STD_LOGIC;

       fct_empty  : OUT STD_LOGIC

      );

END COMPONENT receive_fifo;

COMPONENT state_machine

    GENERIC(

            speed        : NATURAL RANGE 1 TO 100

           );

        PORT(

       --==  General Interface (Sync Rst, 50MHz Clock) ==--

       rst       : IN  STD_LOGIC;

       clk       : IN  STD_LOGIC;

       --== Link Enable Interface ==--

       enable    : IN  STD_LOGIC;

       disable   : IN  STD_LOGIC;

       --== SoCWire Interface ==--

       state     : OUT STD_LOGIC_VECTOR(2 DOWNTO 0);

       --== Character Interface ==--

       got_null  : IN  STD_LOGIC;

       got_fct   : IN  STD_LOGIC;

       got_nchar : IN  STD_LOGIC;

       --== Error Interface ==--

       err_par   : IN  STD_LOGIC;

       err_esc   : IN  STD_LOGIC;

       err_dsc   : IN  STD_LOGIC;

       err_fct   : IN  STD_LOGIC;

       err_nchar : IN  STD_LOGIC;

       --== Active Interface ==--

       active    : OUT STD_LOGIC

      );

END COMPONENT state_machine;

COMPONENT transmitter

  GENERIC(

          bitwidth : NATURAL RANGE 8 TO 8192

         );

        PORT(

       --== General Interface (Sync Rst, 50MHz Clock) ==--

       rst        : IN  STD_LOGIC;

       clk        : IN  STD_LOGIC;

       --== SoCWire Interface ==--

       state      : IN  STD_LOGIC_VECTOR(2 DOWNTO 0);

       --== External Transmit Interface ==--

       tx                 : OUT STD_LOGIC_VECTOR(bitwidth+1 DOWNTO 0);

       tx_valid   : OUT STD_LOGIC;

       --== Data Input Interface ==--

       dat_full   : OUT STD_LOGIC;

       dat_nwrite : IN  STD_LOGIC;

       dat_din    : IN  STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== FCT Input Interface ==--

       fct_full   : OUT STD_LOGIC;

       fct_nwrite : IN  STD_LOGIC

      );

END COMPONENT transmitter;

COMPONENT transmit_fifo

  GENERIC(

          bitwidth : NATURAL RANGE 8 TO 8192

         );

        PORT(

       --== General Interface (Sync Rst, 50MHz Clock) ==--

       rst        : IN  STD_LOGIC;

       clk        : IN  STD_LOGIC;

       --== SoCWire Interface ==--

       state      : IN  STD_LOGIC_VECTOR(2 DOWNTO 0);

       --== Data Input Interface ==--

       dat_full   : OUT STD_LOGIC;

       dat_nwrite : IN  STD_LOGIC;

       dat_din    : IN  STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== Data Output Interface ==--

       dat_nread  : IN  STD_LOGIC;

       dat_empty  : OUT STD_LOGIC;

       dat_dout   : OUT STD_LOGIC_VECTOR(bitwidth DOWNTO 0);

       --== FCT Input Interface ==--

       fct_full   : OUT STD_LOGIC;

       fct_nwrite : IN  STD_LOGIC

      );

END COMPONENT transmit_fifo;

BEGIN

  ---===================================================---

  --== TESTBENCH : Show State more clearly : TESTBENCH ==--

  ---===================================================---

  codec_state <= error_reset WHEN (state = st_error_reset) ELSE

                 error_wait  WHEN (state = st_error_wait) ELSE

                 ready       WHEN (state = st_ready) ELSE

                 started     WHEN (state = st_started) ELSE

                 connecting  WHEN (state = st_connecting) ELSE

                 run         WHEN (state = st_run) ELSE

                 unknown_1   WHEN (state = st_unknown_1) ELSE

                 unknown_2   WHEN (state = st_unknown_2) ELSE

                 baffled;

  ---======================---

  --== SoCWire Receiver ==--

  ---======================---

  U0 : receiver

    GENERIC MAP

          ( speed => speed,

            bitwidth => bitwidth )

    PORT MAP

      (--==  General Interface (Sync Rst) ==--

       rst       => rst,

       clk       => clk,

       --== SoCWire Interface ==--

       state     => state,

       --== External Receive Interface ==--

       rx                => rx,

       rx_valid  => rx_valid,

       --== Character Interface ==--

       got_null  => got_null,

       got_fct   => got_fct,

       got_nchar => got_nchar,

       --== Error Interface ==--

       err_par   => err_par,

       err_esc   => err_esc,

       err_dsc   => err_dsc,

       err_fct   => err_fct,

       err_nchar => err_nchar,

       --== Data Output Interface ==--

       dat_nread => dat_full_i,

       dat_empty => dat_nwrite_i,

       dat_dout  => dat_din_i,

       --== FCT Output Interface ==--

       fct_nread => fct_full_i,

       fct_empty => fct_nwrite_i

      );

  ---================---

  --== Receive FIFO ==--

  ---================---

  U1 : receive_fifo

      GENERIC MAP

          ( bitwidth => bitwidth )

    PORT MAP

      (--==  General Interface (Sync Rst) ==--

       rst        => rst,

       clk        => clk,

       --== SoCWire Interface ==--

       state      => state,

       --== Data Input Interface ==--

       dat_full   => dat_full_i,

       dat_nwrite => dat_nwrite_i,

       dat_din    => dat_din_i,

       --== Data Output Interface ==--

       dat_nread  => dat_nread,

       dat_empty  => dat_empty,

       dat_dout   => dat_dout,

       --== FCT Output Interface ==--

       fct_nread  => fct_nread_i,

       fct_empty  => fct_empty_i

      );

  ---===========================---

  --== SoCWire State Machine ==--

  ---===========================---

  U2 : state_machine

    GENERIC MAP

          ( speed =>  speed )

    PORT MAP

      (--==  General Interface (Sync Rst, 50MHz Clock) ==--

       rst       => rst,

       clk       => clk,

       --== Link Enable Interface ==--

       enable    => enable,

       disable   => disable,

       --== SoCWire Interface ==--

       state     => state,

       --== Character Interface ==--

       got_null  => got_null,

       got_fct   => got_fct,

       got_nchar => got_nchar,

       --== Error Interface ==--

       err_par   => err_par,

       err_esc   => err_esc,

       err_dsc   => err_dsc,

       err_fct   => err_fct,

       err_nchar => err_nchar,

       --== Active Interface ==--

       active    => active

      );

  ---=========================---

  --== SoCWire Transmitter ==--

  ---=========================---

  U3 : transmitter

    GENERIC MAP

          ( bitwidth =>  bitwidth )

    PORT MAP

      (--== General Interface (Sync Rst, 50MHz Clock) ==--

       rst        => rst,

       clk        => clk,

       --== SoCWire Interface ==--

       state      => state,

       --== External Transmit Interface ==--

       tx                 => tx,

       tx_valid   => tx_valid,

       --== Data Input Interface ==--

       dat_full   => dat_nread_i,

       dat_nwrite => dat_empty_i,

       dat_din    => dat_dout_i,

       --== FCT Input Interface ==--

       fct_full   => fct_nread_i,

       fct_nwrite => fct_empty_i

      );

  ---====================---

  --== Transmitter FIFO ==--

  ---====================---

  U4 : transmit_fifo

    GENERIC MAP

          ( bitwidth =>  bitwidth )

    PORT MAP

      (--== General Interface (Sync Rst, 50MHz Clock) ==--

       rst        => rst,

       clk        => clk,

       --== SoCWire Interface ==--

       state      => state,

       --== Data Input Interface ==--

       dat_full   => dat_full,

       dat_nwrite => dat_nwrite,

       dat_din    => dat_din,

       --== Data Output Interface ==--

       dat_nread  => dat_nread_i,

       dat_empty  => dat_empty_i,

       dat_dout   => dat_dout_i,

       --== FCT Input Interface ==--

       fct_full   => fct_full_i,

       fct_nwrite => fct_nwrite_i

      );

END rtl;