std_logic_class.pkg

6端口寄存器IP内核VHDL源代码

-- +------------------------------------
-- | Library: VFP
-- | Designer: Tim Pagden
-- | Opened: 25 Nov 1992
-- +------------------------------------

library IEEE;

package std_logic_class is
  use IEEE.std_logic_1164.all;
  
  -- extensions to IEEE.std_logic_1164
  -- std_logic-related types defined in std_logic_1164
  -- std_logic_class serves 2 purposes:
  -- (i) to implement everything missing from std_logic_1164 (and numeric_std!)
  -- (ii) to add additional vector-based types and functions

  -- (i)
  -- arithmetic operators
  function "+"   (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "+"   (a, b: std_logic_vector)  return std_logic_vector;   -- 23.11.92
  function "-"   (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "*"   (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "/"   (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "mod" (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "rem" (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "**"  (a, b: std_ulogic_vector) return std_ulogic_vector;  -- 23.11.92
  function "+"   (a: std_ulogic_vector)    return std_ulogic_vector;  -- 23.11.92
  function "-"   (a: std_ulogic_vector)    return std_ulogic_vector;  -- 23.11.92
  function "abs" (a: std_ulogic_vector)    return std_ulogic_vector;  -- 23.11.92

  -- general purpose functions
  function longest (a, b: std_ulogic_vector) return integer;  -- 25.11.92
  function longest (a, b: std_logic_vector) return integer;   -- 25.11.92

  -- hardware functions
  function posedge (signal a: std_ulogic) return boolean;     -- 04.12.92
  function negedge (signal a: std_ulogic) return boolean;     -- 04.12.92

  -- mathematical functions
  function log_2 (a: std_ulogic_vector) return integer;       -- 15.11.95

  -- (ii)
  -- arithmetic array type definitions
  -- std_ulogic is defined in std_logic_1164
  -- arithmetic arrays of std_logic are defined in IEEE.numeric_std
  type twos_complement is array (natural range <>) of std_ulogic; -- 27.02.93
  type binary is array (natural range <>) of std_ulogic; -- 28.12.97
  -- integer-range array type definitions
  type vfp_ulogic is ('U', 'X', '0', '1', 'Z', 'W', 'L', 'H', '-'); -- 28.12.97
  type vfp_ulogic_vector is array (integer range <>) of vfp_ulogic; -- 28.12.97

  type  ulogic_2_vector is array (integer range <>) of std_ulogic_vector( 1 downto 0); -- 28.12.97
  type  ulogic_3_vector is array (integer range <>) of std_ulogic_vector( 2 downto 0); -- 28.12.97
  type  ulogic_4_vector is array (integer range <>) of std_ulogic_vector( 3 downto 0); -- 28.12.97
  type  ulogic_5_vector is array (integer range <>) of std_ulogic_vector( 4 downto 0); -- 28.12.97
  type  ulogic_6_vector is array (integer range <>) of std_ulogic_vector( 5 downto 0); -- 28.12.97
  type  ulogic_7_vector is array (integer range <>) of std_ulogic_vector( 6 downto 0); -- 28.12.97
  type  ulogic_8_vector is array (integer range <>) of std_ulogic_vector( 7 downto 0); -- 28.12.97
  type ulogic_16_vector is array (integer range <>) of std_ulogic_vector(15 downto 0); -- 28.12.97 
  type ulogic_21_vector is array (integer range <>) of std_ulogic_vector(20 downto 0); -- 28.12.97 
  type ulogic_32_vector is array (integer range <>) of std_ulogic_vector(31 downto 0); -- 28.12.97
  
  type nibble is array (3 downto 0)  of std_ulogic; -- 30.09.93
  type byte   is array (7 downto 0)  of std_ulogic; -- 30.09.93
  type word   is array (15 downto 0) of std_ulogic; -- 30.09.93
  type dword  is array (31 downto 0) of std_ulogic; -- 30.09.93
  type qword  is array (63 downto 0) of std_ulogic; -- 30.09.93
  
  type byte_vector is array (integer range <>) of byte;    -- 28.12.97
  type word_vector is array (integer range <>) of word;    -- 28.12.97
  type dword_vector is array (integer range <>) of dword;  -- 28.12.97
  type qword_vector is array (integer range <>) of qword;  -- 28.12.97

  -- twos_complement functions
  -- logical operators
  function "not"  (a: twos_complement)    return twos_complement;     -- 25.11.92
  function "and"  (a, b: twos_complement) return twos_complement;     -- 25.11.92
  function "or"   (a, b: twos_complement) return twos_complement;     -- 25.11.92  
  function "xor"  (a, b: twos_complement) return twos_complement;     -- 25.11.92
  function "nand" (a, b: twos_complement) return twos_complement;     -- 25.11.92
  function "nor"  (a, b: twos_complement) return twos_complement;     -- 25.11.92  
  -- function "xnor" (a, b: twos_complement) return twos_complement;  -- 25.11.92
  -- arithmetic operators
  function "+"   (a, b: twos_complement) return twos_complement;    -- 25.11.92
  function "-"   (a, b: twos_complement) return twos_complement;    -- 25.11.92
  function "*"   (a, b: twos_complement) return twos_complement;    -- 25.11.92
  function "/"   (a, b: twos_complement) return twos_complement;    -- 25.11.92
  function "mod" (a, b: twos_complement) return twos_complement;  -- 25.11.92
  function "rem" (a, b: twos_complement) return twos_complement;  -- 25.11.92
  function "**"  (a, b: twos_complement) return twos_complement;   -- 25.11.92
  function "+"   (a: twos_complement)    return twos_complement;       -- 25.11.92
  function "-"   (a: twos_complement)    return twos_complement;       -- 25.11.92
  function "abs" (a: twos_complement)    return twos_complement;     -- 25.11.92
  -- shift operators

  -- general purpose functions
  function longest     (a, b: twos_complement) return integer;      -- 20.03.92
  function abs_wordlength (a: twos_complement) return integer;  -- 20.03.92

  -- hardware functions
  -- none yet defined

  -- mathematical functions
  -- none yet defined

end std_logic_class;