Subversion Repositories iicmb

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

--                                                                             |

--    Project: IIC Multiple Bus Controller (IICMB)                             |

--                                                                             |

--    Module:  Main package.                                                   |

--    Version:                                                                 |

--             1.0,   April 29, 2016                                           |

--                                                                             |

--    Author:  Sergey Shuvalkin, (sshuv2@opencores.org)                        |

--                                                                             |

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

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

-- Copyright (c) 2016, Sergey Shuvalkin                                        |

-- All rights reserved.                                                        |

--                                                                             |

-- Redistribution and use in source and binary forms, with or without          |

-- modification, are permitted provided that the following conditions are met: |

--                                                                             |

-- 1. Redistributions of source code must retain the above copyright notice,   |

--    this list of conditions and the following disclaimer.                    |

-- 2. Redistributions in binary form must reproduce the above copyright        |

--    notice, this list of conditions and the following disclaimer in the      |

--    documentation and/or other materials provided with the distribution.     |

--                                                                             |

-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |

-- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE   |

-- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE  |

-- ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE    |

-- LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR         |

-- CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF        |

-- SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS    |

-- INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN     |

-- CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)     |

-- ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE  |

-- POSSIBILITY OF SUCH DAMAGE.                                                 |

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

library ieee;

use ieee.std_logic_1164.all;

use ieee.numeric_std.all;

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

package iicmb_pkg is

  ------------------------------------------------------------------------------

  -- Byte level master mode commands' codes:

  ------------------------------------------------------------------------------

  -- Start                           --> Done | Arbitration Lost

  -- Byte Write                      --> Done | Write Not Acknowledged | Arbitration Lost | Error

  -- Byte Read                       --> Byte Received | Error

  -- Byte Read with Not-Acknowledge  --> Byte Received | Arbitration Lost | Error

  -- Stop                            --> Done

  -- Set Bus                         --> Done | Error

  -- Wait                            --> Done | Error

  constant mcmd_wait     : std_logic_vector(2 downto 0) := "000";

  constant mcmd_write    : std_logic_vector(2 downto 0) := "001";

  constant mcmd_read_ack : std_logic_vector(2 downto 0) := "010";

  constant mcmd_read_nak : std_logic_vector(2 downto 0) := "011";

  constant mcmd_start    : std_logic_vector(2 downto 0) := "100";

  constant mcmd_stop     : std_logic_vector(2 downto 0) := "101";

  constant mcmd_set_bus  : std_logic_vector(2 downto 0) := "110";

  ------------------------------------------------------------------------------

  ------------------------------------------------------------------------------

  -- Byte level master mode responses' codes:

  ------------------------------------------------------------------------------

  -- Done

  -- Byte received

  -- Write Not Acknowledged

  -- Arbitration lost

  -- Error

  constant mrsp_done     : std_logic_vector(2 downto 0) := "000";

  constant mrsp_nak      : std_logic_vector(2 downto 0) := "001";

  constant mrsp_arb_lost : std_logic_vector(2 downto 0) := "010";

  constant mrsp_error    : std_logic_vector(2 downto 0) := "011";

  constant mrsp_byte     : std_logic_vector(2 downto 0) := "100";

  ------------------------------------------------------------------------------

  ------------------------------------------------------------------------------

  -- Sequencer related stuff ---------------------------------------------------

  type seq_cmd_id is (seq_wait, seq_set_bus, seq_write_byte);

  type seq_cmd_type is record

    id    : seq_cmd_id;

    saddr : std_logic_vector(6 downto 0);

    daddr : std_logic_vector(7 downto 0);

    data  : std_logic_vector(7 downto 0);

  end record;

  constant c_seq_cmd_default : seq_cmd_type := (id => seq_wait, others => (others => '0'));

  type seq_cmd_type_array is array (natural range <>) of seq_cmd_type;

  constant c_empty_array : seq_cmd_type_array(0 to 0) := (others => c_seq_cmd_default); -- not really empty

  function scmd_wait(a : integer range 0 to 255) return seq_cmd_type;

  function scmd_set_bus(a : integer range 0 to 15) return seq_cmd_type;

  function scmd_write_byte(sa : std_logic_vector(6 downto 0);

                           da : std_logic_vector(7 downto 0);

                           d  : std_logic_vector(7 downto 0)) return seq_cmd_type;

  -- End of sequencer related stuff --------------------------------------------

  ------------------------------------------------------------------------------

end package iicmb_pkg;

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

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

package body iicmb_pkg is

  ------------------------------------------------------------------------------

  function scmd_wait(a : integer range 0 to 255) return seq_cmd_type is

    variable ret : seq_cmd_type;

  begin

    ret.id    := seq_wait;

    ret.saddr := (others => '0');

    ret.daddr := (others => '0');

    ret.data  := std_logic_vector(to_unsigned(a, 8));

    return ret;

  end function scmd_wait;

  ------------------------------------------------------------------------------

  ------------------------------------------------------------------------------

  function scmd_set_bus(a : integer range 0 to 15) return seq_cmd_type is

    variable ret : seq_cmd_type;

  begin

    ret.id    := seq_set_bus;

    ret.saddr := (others => '0');

    ret.daddr := (others => '0');

    ret.data  := std_logic_vector(to_unsigned(a, 8));

    return ret;

  end function scmd_set_bus;

  ------------------------------------------------------------------------------

  ------------------------------------------------------------------------------

  function scmd_write_byte(sa : std_logic_vector(6 downto 0);

                           da : std_logic_vector(7 downto 0);

                           d  : std_logic_vector(7 downto 0)) return seq_cmd_type is

    variable ret : seq_cmd_type;

  begin

    ret.id    := seq_write_byte;

    ret.saddr := sa;

    ret.daddr := da;

    ret.data  := d;

    return ret;

  end function scmd_write_byte;

  ------------------------------------------------------------------------------

end package body iicmb_pkg;

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