-------------------------------------------------------------------------------
-- Title      : vga package
-- Project    : LU Digital Design
-------------------------------------------------------------------------------
-- File       : vga_pak.vhd
-- Author     : Thomas Handl
-- Company    : TU Wien
-- Created    : 2004-08-19
-- Last update: 2006-02-24
-------------------------------------------------------------------------------
-- Description: definitions of global constants and enumerated types
-------------------------------------------------------------------------------
-- Copyright (c) 2004 TU Wien
-------------------------------------------------------------------------------
-- Revisions  :
-- Date        Version  Author  Description
-- 2004-08-19  1.0      handl   Created
-- 2006-02-24  2.0      ST      revised
-------------------------------------------------------------------------------

-------------------------------------------------------------------------------
-- LIBRARIES
-------------------------------------------------------------------------------

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_unsigned.all;
use IEEE.std_logic_arith.all;


-------------------------------------------------------------------------------
-- PACKAGE
-------------------------------------------------------------------------------

package vga_pak is

  constant RES_ACT   : std_logic := '0';            -- define reset active LO
  constant ENABLE    : std_logic := '1';            -- define diverse enable HI
  constant COLR_ON    : std_logic := '1';           -- define VGA color on as HI
  constant COLR_OFF   : std_logic := '0';           -- define VGA color off as LO
  constant SEG_WIDTH : integer := 7;                -- display has 7 segments
  constant BCD_WIDTH : integer := 4;                -- BCD number has 4 bit
  constant TOG_CNT_WIDTH : integer := 25;           -- bitwidth of counter that controls blinking

  constant COL_CNT_WIDTH   : integer := 10;          -- width of the column counter
  constant LINE_CNT_WIDTH  : integer := 9;           -- width of the line counter
  constant HSYN_CNT_WIDTH : integer := 10;          -- width of the h-sync counter
  constant VSYN_CNT_WIDTH : integer := 10;          -- width of the v-sync counter

  constant RIGHT_BORDER:  std_logic_vector(COL_CNT_WIDTH-1 downto 0) := "1001111111";  -- 640 columns (0...639)
  constant BOTTOM_BORDER: std_logic_vector(LINE_CNT_WIDTH-1 downto 0) := "111011111";   -- 480 lines (0...479)

  -- define coordinates of rectangle
  constant X_MIN : std_logic_vector(COL_CNT_WIDTH-1 downto 0) := "0001100100";  -- 100
  constant X_MAX : std_logic_vector(COL_CNT_WIDTH-1 downto 0) := "0011001000";  -- 200
  constant Y_MIN : std_logic_vector(LINE_CNT_WIDTH-1 downto 0) := "001100100";
  constant Y_MAX : std_logic_vector(LINE_CNT_WIDTH-1 downto 0) := "011001000";

  -- define emumerated types for state machines
  type hsync_state_type is (RESET_STATE, B_STATE, C_STATE, D_STATE, E_STATE,
                            pre_D_STATE, pre_B_STATE);
  type vsync_state_type is (RESET_STATE, P_STATE, Q_STATE, R_STATE, S_STATE,
                            pre_R_STATE, pre_P_STATE);
  
  --  Definitions for 7-segment display                             gfedcba
  constant DIGIT_ZERO  : std_logic_vector(SEG_WIDTH-1 downto 0) := "1000000";
  constant DIGIT_ONE   : std_logic_vector(SEG_WIDTH-1 downto 0) := "1111001";
  constant DIGIT_TWO   : std_logic_vector(SEG_WIDTH-1 downto 0) := "0100100";
  constant DIGIT_THREE : std_logic_vector(SEG_WIDTH-1 downto 0) := "0110000";
  constant DIGIT_FOUR  : std_logic_vector(SEG_WIDTH-1 downto 0) := "0011001";
  constant DIGIT_FIVE  : std_logic_vector(SEG_WIDTH-1 downto 0) := "0010010";
  constant DIGIT_SIX   : std_logic_vector(SEG_WIDTH-1 downto 0) := "0000010";
  constant DIGIT_SEVEN : std_logic_vector(SEG_WIDTH-1 downto 0) := "1111000";
  constant DIGIT_EIGHT : std_logic_vector(SEG_WIDTH-1 downto 0) := "0000000";
  constant DIGIT_NINE  : std_logic_vector(SEG_WIDTH-1 downto 0) := "0011000";
  constant DIGIT_MINUS : std_logic_vector(SEG_WIDTH-1 downto 0) := "0111111";
  constant DIGIT_A     : std_logic_vector(SEG_WIDTH-1 downto 0) := "0001000";
  constant DIGIT_B     : std_logic_vector(SEG_WIDTH-1 downto 0) := "0000011";
  constant DIGIT_C     : std_logic_vector(SEG_WIDTH-1 downto 0) := "0110001";
  constant DIGIT_D     : std_logic_vector(SEG_WIDTH-1 downto 0) := "1000010";
  constant DIGIT_E     : std_logic_vector(SEG_WIDTH-1 downto 0) := "1001111";
  constant DIGIT_F     : std_logic_vector(SEG_WIDTH-1 downto 0) := "1000111";
  constant DIGIT_OFF   : std_logic_vector(SEG_WIDTH-1 downto 0) := "1111111";
 
end package;