library ieee;
use ieee.std_logic_1164.all;


package LCD_pkg is

-- THE HEAP O' CONSTANTS
--
-- These are 8-bit patterns which may or may not be used in interfacing
-- to the LCD 8-bit data bus. They are here to improve readability in the
-- code, which I suppose is the idea of constants in the first place. Oh,
-- and to improve maintainability, but this really only applies to the
-- CLOCK_COUNT constant, as the other constants are pretty well set in
-- stone, unless if another type of LCD is being used.

subtype charcode is std_logic_vector( 7 downto 0 );

-- Clear screen.
constant CLR:   charcode := "00000001";

-- Display ON, with cursor.
constant DON:   charcode := "00001111";

-- Set Entry Mode to increment cursor automatically after each character
-- is displayed.
constant SEM:   charcode := "00000110";

-- Home cursor
constant HOME:  charcode := "00000010";

-- Function set for 8-bit data transfer and 2-line display and display off
constant SET:   charcode := "00111100";
 
 
-- The alphabet - UPPER CASE only.
constant A:     charcode := "01000001";
constant B:     charcode := "01000010";
constant C:     charcode := "01000011";
constant D:     charcode := "01000100";
constant E:     charcode := "01000101";
constant F:     charcode := "01000110";
constant G:     charcode := "01000111";
constant H:     charcode := "01001000";
constant I:     charcode := "01001001";
constant J:     charcode := "01001010";
constant K:     charcode := "01001011";
constant L:     charcode := "01001100";
constant M:     charcode := "01001101";
constant N:     charcode := "01001110";
constant O:     charcode := "01001111";
constant P:     charcode := "01010000";
constant Q:     charcode := "01010001";
constant R:     charcode := "01010010";
constant S:     charcode := "01010011";
constant T:     charcode := "01010100";
constant U:     charcode := "01010101";
constant V:     charcode := "01010110";
constant W:     charcode := "01010111";
constant X:     charcode := "01011000";
constant Y:     charcode := "01011001";
constant Z:     charcode := "01011010";

-- Numbers
constant zero:  charcode := "00110000";
constant one:   charcode := "00110001";
constant two:   charcode := "00110010";
constant three: charcode := "00110011";
constant four:  charcode := "00110100";
constant five:  charcode := "00110101";
constant six:   charcode := "00110110";
constant seven: charcode := "00110111";
constant eight: charcode := "00111000";
constant nine:  charcode := "00111001";

-- Some potentially useful puctuation. 
constant SP:    charcode := "00100000";         -- Space
constant BRL:   charcode := "00101000";         -- Left Bracket
constant BRR:   charcode := "00101001";         -- Right Bracket
constant DASH:  charcode := "00101101";         -- Dash, as in hypen
constant COLON: charcode := "00111010";         -- Colon:  :
constant APO:   charcode := "00100111";         -- Apostrophe
constant star:  charcode := "00101010";         -- *
constant pound: charcode := "00100011";         -- #

-- other constants
constant lastposition: integer:=16;     -- LCD display length
constant LEDseg : positive := 7;
constant LCDdatasize: positive:= 8;

component LCDdriver is 
generic( big_delay: integer := 2000;
		 small_delay: integer :=100;
		 setup_delay: integer := 50
		);
		port(
        clock: in std_logic;
        reset: in std_logic;
        message: in std_logic_vector( 7 downto 0 );
        enable: in std_logic; -- detect if there is any incoming message
        lcd_data: out std_logic_vector( 7 downto 0 );
        lcd_rs: out std_logic;
        lcd_rw: out std_logic;
        lcd_enable: out std_logic;
        LED1: out std_logic_vector( 6 downto 0 );
        LED2: out std_logic_vector( 6 downto 0 )
		);
end component LCDdriver;

end LCD_pkg;