Subversion Repositories gamepads

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

--

-- SNESpad controller core

--

-- Copyright (c) 2004, Arnim Laeuger (arniml@opencores.org)

--

-- $Id: snespad_pack-p.vhd,v 1.1 2004-10-05 17:01:27 arniml Exp $

--

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

library ieee;

use ieee.std_logic_1164.all;

package snespad_pack is

  constant num_buttons_c : natural := 12;

  subtype  buttons_t is std_logic_vector(num_buttons_c-1 downto 0);

  subtype  num_buttons_read_t is natural range 0 to num_buttons_c-1;

  function button_active_f(state : in std_logic; ref : in natural) return std_logic;

  function button_reset_f(ref : in natural) return std_logic;

  function "=" (a : std_logic; b : integer) return boolean;

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

  -- The button positions inside the SNES packet

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

  constant but_pos_b_c     : natural := 11;

  constant but_pos_y_c     : natural := 10;

  constant but_pos_sel_c   : natural := 9;

  constant but_pos_start_c : natural := 8;

  constant but_pos_up_c    : natural := 7;

  constant but_pos_down_c  : natural := 6;

  constant but_pos_left_c  : natural := 5;

  constant but_pos_right_c : natural := 4;

  constant but_pos_a_c     : natural := 3;

  constant but_pos_x_c     : natural := 2;

  constant but_pos_tl_c    : natural := 1;

  constant but_pos_tr_c    : natural := 0;

end snespad_pack;

package body snespad_pack is

  function button_active_f(state : in std_logic; ref : in natural) return std_logic is

    variable result_v : std_logic;

  begin

    if ref = 0 then

      result_v := state;

    else

      result_v := not state;

    end if;

    return result_v;

  end button_active_f;

  function button_reset_f(ref : in natural) return std_logic is

    variable result_v : std_logic;

  begin

    if ref = 0 then

      result_v := '1';

    else

      result_v := '0';

    end if;

    return result_v;

  end button_reset_f;

  function "=" (a : std_logic; b : integer) return boolean is

    variable result_v : boolean;

  begin

    result_v := false;

    case a is

      when '0' =>

        if b = 0 then

          result_v := true;

        end if;

      when '1' =>

        if b = 1 then

          result_v := true;

        end if;

      when others =>

        null;

    end case;

    return result_v;

  end;

end snespad_pack;